american samoa - University of Hawaii at Manoa Botany Department

Asili StreamAMERICAN SAMOAWETLAND/STREAMRESTORATION AND ENHANCEMENT PLANVatia Wetland

AMERICAN SAMOAWETLAND/STREAMRESTORATION AND ENHANCEMENT PLANPrepared for:American Samoa Environmental Protection AgencyandAmerican Samoa Coastal Management ProgramPago Pago, American Samoa 96799Prepared by:Pedersen Planning ConsultantsP. O. Box 1075Saratoga, Wyoming 82331-1075Tel: (307) 327-5434 Fax: (307) 327-5210E-mail: ppc@union-tel.comFebruary 2001

American SamoaWetland/Stream Restoration and Enhancement PlanTABLE OF CONTENTSChapter No. Title Page No.OneTwoThreeFourFiveSixINTRODUCTIONPurposeScopeOrganization of the ReportPlan MethodologyPublic ConsultationTULA WETLANDLocationWetland HydrologyWetland VegetationAquatic Fish and InvertebratesLand Uses in the Vicinity of Tula WetlandWetland Restoration and Enhancement StrategiesALAO WETLANDLocationWetland HydrologyWetland VegetationAquatic Fish and InvertebratesLand Uses in the Vicinity of Taufusi MarshWetland Restoration and Enhancement StrategiesAOA WETLANDLocationWetland HydrologyWetland VegetationAquatic Fish and InvertebratesLand Uses in the Vicinity of Aoa WetlandWetland Restoration and Enhancement StrategiesVATIA WETLANDLocationWetland HydrologyWetland VegetationAquatic Fish and InvertebratesLand Uses within Southeast Wetland and Faatafe StreamWetland Restoration and Enhancement StrategiesVAIPITO STREAMLocationStream HydrologyVegetationAquatic Fish and InvertebratesLand Uses Adjacent to Vaipito StreamRiparian Restoration and Enhancement Strategies1-11-11-11-31-31-62-12-12-12-52-62-72-73-13-13-13-43-73-83-94-14-14-14-54-84-94-105-15-15-15-55-75-95-96-16-16-16-56-76-106-10- i -

American Samoa Wetland/Stream Restoration and Enhancement PlanTABLE OF CONTENTS (continued)ChapterNo.TitlePage No.Seven PAPA STREAMLocationStream HydrologyVegetationAquatic Fish and InvertebratesLand Uses Adjacent to Papa StreamRiparian Restoration and Enhancement OpportunitiesEight SAUINO STREAMLocationStream HydrologyVegetationAquatic Fish and InvertebratesLand Uses Adjacent to Lower Sauino StreamRiparian Restoration and Enhancement OpportunitiesNine LEAFU STREAMLocationStream HydrologyVegetationAquatic Fish and InvertebratesLand Uses Adjacent to Vaipito StreamRiparian Restoration and Enhancement OpportunitiesTen ASILI STREAMLocationStream HydrologyVegetationAquatic Fish and InvertebratesLand Uses Adjacent to Asili StreamRiparian Restoration and Enhancement OpportunitiesEleven FUSI WETLANDLocationWetland HydrologyWetland VegetationAquatic Fish and InvertebratesLand Uses in the Vicinity of Fusi WetlandWetland Restoration and Enhancement StrategiesTwelve FUTURE PROGRAM MANAGEMENTRecommended Program ParticipantsIndividual Project AssignmentsSelected Agency AssignmentsPotential Participation from Other Community OrganizationsAPPENDIX A – Summary of Plants, November 1999APPENDIX B – Summary of Aquatic Macrofaunal Organisms, November 1999APPENDIX C – Summary of Aquatic Macrofaunal Organisms, July 1981REFERENCES- ii -7-17-17-17-77-87-97-98-18-18-18-58-68-78-79-19-19-19-59-79-99-910-110-110-110-610-710-910-1011-111-111-111-411-511-611-712-112-112-112-312-3

American Samoa Wetland/Stream Restoration and Enhancement PlanLIST OF FIGURESFigure No. Title Page No.1-1 Location MapPotential Wetlands and Streams Enhancement Opportunities2-1 Location Map, Tula Wetland2-2 Existing Conditions, Tula Wetland2-3 Option 2: Detention of Stormwater Within Tula Wetland2-4 Option 3: Expansion of Taro Production Within Tula Wetland2-5 Resource Monitoring Stations and Areas, Tula Wetland3-13-23-33-44-14-24-34-45-15-25-36-16-26-36-47-17-27-38-18-28-38-49-19-29-39-49-510-110-210-311-111-211-3Location Map, Alao Village WetlandExisting Conditions, Taufusi MarshFEMA 100-Year Flood Plain, Alao VillageOption 2: Restore Taro ProductionLocation Map, Aoa Village WetlandExisting Conditions, Aoa WetlandOption 4: Clear Puna Stream Culvert, Plant TreesResource Monitoring AreasLocation Map, Southeast Wetland in VatiaExisting Conditions, Vatia WetlandOption 1:Restore Mangrove Forest Upstream of Faatafe Stream MouthLocation Map, Vaipito Stream DrainageExisting Conditions, Vaipito StreamFish and Invertebrate Survey LocationsOption 1:Restore Mangrove Forest Along Lower Vaipito StreamLocation Map, Leele-Papa-Tauese Stream DrainageExisting Conditions, Papa Stream SegmentOption 2: Clean Stream, Improve Stream Hydrology, andReduce Bank ErosionLocation Map, Sauino Stream DrainageExisting Conditions, Sauino StreamOption 1: Construct Detention PondOption 2: Plant Native Riparian Trees Along Stream BankLocation Map, Leafu StreamExisting Conditions, Leafu StreamOption 1: Restore Stream Bank in Vicinity of L2Option 2: Construct Basaltic Wall, Stabilize Stream Bank, and EnhanceRiparian VegetationOption 3: Stabilize East Stream Bank and Enhance Riparian VegetationLocation Map, Asili StreamExisting Conditions, Asili StreamOption 1: Clean Asili Stream and Enhance Riparian VegetationLocation Map, Fusi WetlandExisting Conditions, Fusi WetlandOption 1: Remove Solid Waste Material and Plant Wetland MarshVegetation1-22-22-32-92-112-203-23-33-53-104-24-34-124-185-25-35-106-26-36-86-117-27-37-128-28-38-88-109-29-39-109-129-1310-210-310-1111-211-311-8- iii -

American Samoa Wetland/Stream Restoration and Enhancement PlanLIST OF TABLESTable No. Title Page No.2-1 Potential Stormwater Discharges into Tula Wetland2-42, 10, 50 and 100-Year Storm Events2-2 Comparative Evaluation2-13Wetland Restoration and Enhancement OpportunitiesTula Wetland2-3 Preliminary Cost Estimate2-14Development of Channel and Detention PondVailoa Stream Drainage and Tula Wetland2-4 Preliminary Cost Estimate2-15Planting of Wetland and Fruit Trees Along Tula Wetland Margin2-5 Long-term Resource Monitoring Requirements, Tula Wetland 2-172-6 Field Monitoring Worksheet, Tula Wetland 2-18,193-1 Potential Stormwater Discharges into Taufusi Marsh3-4From Mulivaitele Stream and Its Tributaries2, 10, 50 and 100-Year Storm Events3-2 Summary of Macrofaunal Organisms, Mulivaitele Stream 3-83-3 Relative Abundance and Diversity of Fish and Invertebrates3-8Mulivaitele Stream Segment on East Side of Taufusi Marsh3-4 Comparative Evaluation3-12Wetland Restoration and Enhancement OpportunitiesAlao Wetland3-5 Preliminary Cost Estimate3-12Procurement and Distribution of Taro Plant CuttingsAlao Village3-6 Long-Term Resource Monitoring Requirements, Alao Wetland 3-143-7 Field Monitoring Worksheet, Alao Wetland 3-15,164-1 Median Stream Flow Estimate, Lepa Stream 4-14-2 Potential Stormwater Discharges into Aoa Wetland4-4From Tapua and Puna Streams2, 10, 50 and 100-Year Storm Events4-3 Summary of Macrofaunal Organisms4-9Alao Wetland and Lepa Stream4-4 Relative Abundance and Diversity of Fish and Invertebrates4-9Tapua Stream and Lepa Stream4-5 Comparative Evaluation4-13Wetland Restoration and Enhancement OpportunitiesAoa Wetland4-6 Preliminary Cost Estimate4-14Initial Clearing of Puna Stream Culvert4-7 Preliminary Cost Estimate4-14Planting of Mangrove and Riparian TreesUpstream of Tapua and Puna Stream Mouths4-8 Long-Term Resource Monitoring Requirements, Aoa Wetland 4-164-9 Field Monitoring Worksheet, Aoa Wetland 4-17- iv -

American Samoa Wetland/Stream Restoration and Enhancement PlanLIST OF TABLES (continued)Table No. Title Page No.5-1 Potential Stormwater Discharges Along SE Side of Vatia Bay5-42, 10, 50 and 100-Year Storm Events5-2 Summary of Macrofaunal Organisms5-8Vatia Wetland5-3 Relative Abundance and Diversity of Fish and Invertebrates5-8Faatafe Stream5-4 Comparative Evaluation5-12Wetland Restoration and Enhancement OpportunitiesVatia Wetland5-5 Preliminary Cost Estimate5-12Clearing of Faatafe Stream Mouth, Culvert, and Upstream Area5-6 Preliminary Cost Estimate5-13Planting of Mangrove and Riparian TreesUpstream of Faatafe Stream Mouth5-7 Long-Term Resource Monitoring Requirements, Vatia Wetland 5-155-8 Field Monitoring Worksheet, Vatia Wetland 5-16,176-1 Median Stream Flow Estimates, Tributaries of Vaipito Stream 6-46-2 Stormwater Runoff Discharges into Inner Pago Pago Harbor6-4From Vaipito Stream Drainage2, 10, 50 and 100 Year Storm Events6-3 Estimated Vaipito Stream Capacities 6-56-4 Summary of Macrofaunal Organisms6-9Vaipito Stream Drainage6-5 Relative Abundance and Diversity of Fish and Invertebrates6-9Vaipito Stream6-6 Comparative Evaluation6-13Riparian Restoration and Enhancement OpportunitiesLower Vaipito Stream6-7 Preliminary Cost Estimate6-14Clearing of Lower Vaipito Stream Mouth and Upstream Area6-8 Preliminary Cost Estimate6-14Planting of Trees Upstream of Vaipito Stream Mouth6-9 Long-Term Resource Monitoring Requirements, Vaipito Stream 6-166-10 Field Monitoring Worksheet, Vaipito Stream 6-17,18,197-1 Median Stream Flow Estimate, Papa Stream 7-57-2 Stormwater Discharges from Papa Stream Into Pala Lagoon7-62, 10, 50 and 100 Year Storm Events7-3 Cross-Sectional Analysis7-6Along Papa Stream Segment7-4 Summary of Macrofaunal Organisms7-8Papa Stream7-5 Relative Abundance and Diversity of Fish and InvertebratesPapa Stream7-9- v -

American Samoa Wetland/Stream Restoration and Enhancement PlanLIST OF TABLES (Continued)Table No. Title Page No.7-6 Comparative Evaluation7-11Riparian Restoration and Enhancement OpportunitiesLower Papa Stream7-7 Preliminary Cost Estimate7-13Clearing of Lower Papa Stream Mouth7-8 Preliminary Cost Estimate7-14Propagation and Planting of Native Riparian TreesLower Papa Stream7-9 Long-Term Resource Monitoring Requirements, Papa Stream 7-167-10 Field Monitoring Worksheet, Papa Stream 7-17,18,198-1 Median Stream Flow Estimate, Sauino Stream 8-48-2 Stormwater Discharges from Sauino Stream into Pala Lagoon8-41, 20, 50 and 100-Year Storm Events8-3 Summary of Macrofaunal Organisms 8-68-4 Relative Abundance and Diversity of Fish and Invertebrates8-7Lower Sauino Stream Segment8-5 Comparative Evaluation8-11Riparian Restoration and Enhancement OpportunitiesLower Sauino Stream Segment8-6 Preliminary Cost Estimate8-11Planting of Riparian Trees Along Lower Sauino Stream8-7 Long-Term Resource Monitoring Requirements, Sauino Stream 8-138-8 Field Monitoring Worksheet, Sauino Stream 8-14,15,169-1 Measurements from Selected Stream Cross Sections, Leafu Stream 9-49-2 Median Stream Flow Estimates, Leafu Stream 9-49-3 Stormwater Runoff Discharges into Leone Pala9-510, 50, and 100-Year Storm Events9-4 Summary of Macrofaunal Organisms9-8Leafu Stream9-5 Relative Abundance and Diversity of Fish and Invertebrates9-8Lower Leafu Stream9-6 Comparative Evaluation9-14Riparian Restoration and Enhancement OpportunitiesLower Leafu Stream Segment9-7 Preliminary Cost Estimate9-15Propagation and Planting of Riparian TreesAlong Lower Leafu Stream9-8 Long-Term Resource Monitoring Requirements, Leafu Stream 9-179-9 Field Monitoring Worksheet, Leafu Stream 9-18,19- vi -

American Samoa Wetland/Stream Restoration and Enhancement PlanLIST OF TABLES (Continued)Table No. Title Page No.10-1 Median Stream Flow Estimate, Asili Stream 10-410-2 Stormwater Discharges from Asili Stream10-51, 10, 50 and 100-Year Storm Events10-3 Cross-Sectional Analysis10-5Along Asili Stream Segment10-4 Summary of Macrofaunal Organisms10-9Asili Stream10-5 Relative Abundance and Diversity of Fish and Invertebrates10-9Asili Stream10-6 Comparative Evaluation10-12Riparian Restoration and Enhancement OpportunitiesLower Asili Stream10-7 Preliminary Cost Estimate10-13Clean-up of Lower Asili Stream10-8 Preliminary Cost Estimate10-13Propagation and Planting of Native Riparian TreesLower Asili Stream10-9 Long-Term Resource Monitoring Requirements, Asili Stream 10-1510-10 Field Monitoring Worksheet, Asili Stream 10-16,17,1811-1 Relative Abundance and Diversity of Fish and Invertebrates11-6Fusi Wetland11-2 Comparative Evaluation11-9Wetland Restoration and Enhancement OpportunitiesFusi Wetland11-3 Preliminary Cost Estimate11-10Collection, Removal and Hauling of Solid Waste MaterialFusi Wetland11-4 Preliminary Cost Estimate11-10Propagation and Planting of Coastal Marsh VegetationFusi Wetland11-5 Long-Term Resource Monitoring Requirements, Fusi Wetland 11-1211-6 Field Monitoring Worksheet, Fusi Wetland 11-13- vii -

Chapter OneINTRODUCTIONPURPOSEThe American Samoa Environmental Protection Agency, in cooperation with several otheragencies of the American Samoa Government, is undertaking resource management efforts toconserve natural resources on a watershed-by-watershed basis. The American SamoaWatershed Protection Plan provided management recommendations for 41watershed planningareas and recommended the establishment of a Territorial Watershed Resource ManagementBoard to coordinate future implementation. While the Watershed Protection Plan recommendsa wide variety of resource conservation efforts, it is envisioned that a series of more specificresource conservation plans that will eventually supplement and support the recommendationsoutlined in the American Samoa Watershed Protection Plan.The Wetland/Stream Restoration and Enhancement Plan is one example of a more specificresource conservation plan. This plan outlines a more specific strategy for the conservation offive streams and four wetlands on the Island of Tutuila, as well as one wetland on the Island ofTau (Figure 1-1). This information will guide a portion of the future work of the proposedASG Watershed Resource Management Board as it determines specific watershed managementpriorities in several watershed planning areas of the Territory. The Plan will also provide morespecific technical guidance to the various agencies of the American Samoa Government whowill work cooperatively to accomplish the actions necessary to implement conservation effortsat various streams and wetlands.SCOPEIn 1999, representatives of the American Samoa Coastal Management Program, AmericanSamoa Community College Land Grant Program, and American Samoa EnvironmentalProtection Agency evaluated potential opportunities for the restoration and enhancement ofvarious streams and wetlands. In recognition of available funding, the number of stream andwetland sites selected for site evaluation and planning was limited to ten locations.This plan examines potential resource management opportunities to enhance the quality andfunction of five streams and five wetlands. The primary questions addressed with theevaluation of each potential resource location are:1) What feasible opportunities exist for enhancing stream and wetland functions?2) What potential benefits would be gained from enhancement efforts?3) What is the anticipated cost of a potential enhancement program at each site?4) Where feasible, how should enhancement efforts be monitored?5) Who should carry out recommended enhancement efforts?American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-1

Figure 1-1Location of Potential Wetlands and Streams Enhancement OpportunitiesAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-2

ORGANIZATION OF THE REPORTThe Wetland and Stream Enhancement Plan report is organized in the following manner.• Chapter One: Introduction• Chapter Two: Tula Wetland• Chapter Three: Alao Wetland• Chapter Four: Aoa Wetland• Chapter Five: Vatia Wetland• Chapter Six: Vaipito Stream• Chapter Seven: Papa Stream• Chapter Eight: Sauino Stream• Chapter Nine: Leafu Stream• Chapter Ten: Asili Stream• Chapter Eleven: Fusi Wetland (Island of Tau)• Chapter Twelve: Future Program ManagementEach site evaluation describes the characteristics and condition of stream and wetlandhydrology, vegetation, as well as fish and invertebrates. The significance of these resources isevaluated in terms of potential enhancement opportunities. Adjacent land uses are alsoexamined in the context of relevant resource management issues that may influence theapproach to potential restoration and enhancement opportunities.Practical options for wetland and stream restoration and enhancement are provided for each ofthe ten sites. The benefits and consequences of potential options are compared and evaluated.The recommended restoration and enhancement project for each site is described in terms ofscope, location, and anticipated costs.A number of overall program management recommendations are also presented in ChapterTwelve to facilitate future project implementation. These recommendations includeconsiderations of project management, potential program participants, as well as relatedresponsibilities and project coordination.PLAN METHODOLOGYResearch of Other Stream and Wetland Restoration Enhancement ProjectsPedersen Planning Consultants (PPC) initiated the project with a literature search for selectedstream and restoration projects on Pacific Islands, South America, and the continental UnitedStates. An Internet search was used to explore a wide range of stream and wetlandenhancement projects, as well as relevant criteria for the evaluation and assessment of potentialenhancement opportunities.Mr. Dick Wass, manager of the Hakalau Wildlife Refuge on the Island of Hawaii, wasinterviewed by PPC in December 1998. Through his experience with the U.S Fish and WildlifeService and past experience in American Samoa, Mr. Wass provided some insights concerningthe enhancement of wildlife opportunities.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-3

Onsite InvestigationsNovember 1999GeneralFollowing initial site selection, PPC sent a field team of three persons to American Samoa toinvestigate each of the stream and wetland sites in November 1999. PPC field team membersincluded:• Jim Pedersen, principal planner, Pedersen Planning Consultants• Art Whistler, botanist, Isle Botanica• Charles Chong, aquatic biologistPrior to accessing specific sites, the field team made a reasonable attempt to locate and speakwith, at least, one traditional village matai, or a pulenuu of the village. The purpose of the sitevisit was explained. Permission was requested to enter the site. In most cases, other questionsrelating to existing conditions and specific resource management issues were also posed anddiscussed with the selected village representatives and, in some cases, other village residentsencountered during the survey.When schedules permitted, the field team was accompanied by Bronwyn Mitchell, projectmanager and wetland specialist with the American Samoa Coastal Management Program, orColin Steele, director of the American Samoa Community College, Land Grant Program. Bothof these ASG representatives provided valuable insights concerning onsite conditions andpotential resource enhancement opportunities.Field notes and digital photos were taken of selected resource conditions. Digital photos werelater incorporated into a digital photo album for the project. Information gained from villagerepresentatives and residents were also documented.Vegetation SurveyA qualitative survey was also made of vegetation along selected stream segments and wetlandareas. The extent and location of observations at each site varied depended primarily uponstream hydrology characteristics, land uses, and site accessibility. The specific areas surveyedare more specifically mapped and/or described within each site description.The type and relative abundance of the species observed at each site were recorded. In somecases, specific plants were photographed to facilitate future reference.During the survey, special attention was given to plant species that might be threatened orendangered. Determinations were made concerning the type of wetland and streamenvironments, their general boundaries, and which species were dominant.A plant checklist was prepared for all plants observed during the survey (Appendix A). Thischecklist identified scientific, Samoan and English names of all plants observed, and provideduseful notations concerning the wetland status of each plant. The categories of wetland statusused in the checklist included the following:American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-4

• Obligate plant represented any plant species found only in wetlands;• Facultative wetland plant included any plant species that is usually, but not always,found in wetlands;• Facultative plant was considered to be any plant species that is found as much inwetlands as in dry soil;• Facultative upland plant represented any plant that is usually found in upland areas, butsometimes in wetlands; and,• Upland plant was considered to be any plant that is rarely, if ever, found in wetlands.Fish and Invertebrate SurveyA one-time, qualitative survey of aquatic fish, crustaceans, and mollusks was made at streamsegments and selected wetland areas. Two sites, i.e., stream mouth and an upland streamlocation, were sampled for streams that flowed into the ocean at the time of the survey. Theextent and location of observations at each site varied depended primarily upon streamhydrology characteristics, land uses, and site accessibility. The specific areas surveyed aremapped and/or described within each site description. An overall summary of macrofaunalorganisms observed is presented in Appendix B.Fish and invertebrate survey sites were approximately 30 meters long. Each site was inspectedmoving upstream and all macrofaunal organisms were visually recorded. The types of species,relative abundance, and general diversity were documented for stream mouth, upland stream,and wetland sites. Visual observations were made at the surface, as well as underwater whereadequate flow was present.Three Surber samples were made at survey sites where cobble substrata were present andstream flow velocities were sufficient. The Surber samples were taken in the middle of thestream approximately 10 meters apart. If substrata and stream flow characteristics were notappropriate for use of the Surber net, three individual rocks in a site were selected and cleanedcompletely with a stiff brush to collect and benthic invertebrates present. However, there wasonly one species of chironomid larvae found in very low densities in any of the samples.Consequently, no results were reported for benthic fauna.Wetland and Stream Hydrology AssessmentPPC also made assessments of stream hydrology at each wetland and stream site to identifypotential opportunities for wetland and stream restoration and enhancement. A walk throughwas made along selected stream channels and wetlands to ascertain the potential locations,causes, and impacts of:• significant stream bank erosion;• changes in stream flow path;• stream modifications such as man-made stream channels;• impeded surface water discharges to and from wetlands; and,• changes in land uses along stream channels, as well as within and along the perimeterof wetlands.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-5

Where appropriate, stream cross sections were measured at 100-foot intervals to facilitate thesubsequent modeling of stormwater discharge capacities and long-term monitoring of streamcharacteristics. Digital photos were taken of significant stream and wetland characteristics.In 1998 and 1999, Pedersen Planning Consultants had previously modeled and quantifiedpotential storm runoff and sedimentation from 2, 10, 50 and 100-year storm events for Papa,Sauino, Vaipito, and Leafu streams, as well as the Tula wetland. PPC also had evaluatedpotential stormwater detention opportunities at these and several other sites on the Island ofTutuila. Consequently, PPC was already aware of flow capacity issues for several of the sitesbeing evaluated in the Wetland and Stream Restoration and Enhancement Plan. The capacityof the remaining stream and wetland sites included in the Wetland and Stream Restoration andEnhancement Plan were modeled following completion of the November, 1999 field survey.Changes in land use were also documented by PPC and compared to land use surveyinformation obtained by PPC in December, 1994. This information was collected andincorporated into the GIS developed for ASEPA in 1998 and 1999.Information gained from field observations, hydraulic modeling data, and discussions withlocal residents enabled PPC to evaluate hydrologic options for stream bank stabilization, therestoration of stream flow paths, and the detention of stormwater flows within selectedwetlands.June 2000A second reconnaissance was made of selected segments of lower Papa Stream in June 2000.This brief survey was made by Joshua Craig of the American Samoa Environmental ProtectionAgency and Jim Pedersen of Pedersen Planning Consultants.Stream modifications immediately downstream and upstream of a former Navy weir weresurveyed. Digital photos were taken of stream bank alterations along the west stream bank thatwere completed after the November, 1999 field survey. PPC also observed streammodifications several hundred feet upstream of the former Navy weir (see Chapter Seven)where stream modifications had apparently generated significant downstream bank erosion andaltered the stream flow path. Local residents also provided valuable insights concerning thecauses and effects of past and recent stream modifications.PUBLIC CONSULTATIONThe following individuals and agency representatives were contacted during the course of thisproject. Their insights and experience provided useful information to the PPC project team.American Samoa Environmental Protection AgencySheila Wiegman, deputy directorJoshua Craig, environmental scientistAmerican Samoa Coastal Management ProgramBronwyn Mitchell, wetland specialistAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-6

American Samoa Community College, Land Grant ProgramColin Steele, ASCC/AHNR Project ForesterAsili VillageSenator Tago, matai and faipulePetasi Toita, matai and 80-year resident of Asili VillageAlao VillageTulafale Satele, talking chiefMalia Puaauli, resident on southeast side of Alao wetlandAoa VillageTautala Taase, matai and pulenuuFaamaoni Afusia, resident on northwest side of Aoa wetlandLeone VillageTui Faafili, 20-year resident of LeoneNuuuli VillageSainila Fanene, mataiAiakopu Samuelo, resident and building contractorGeorge Galeai, building contractor and resident along Papa StreamTula VillageFaasou Pulou, mataiU.S. National Park ServicePeter CraigU.S. Fish and Wildlife Service, Hakalau Wildlife Refuge, Island of HawaiiDick Wass, ManagerAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Introduction, Page 1-7

Chapter TwoTULA WETLANDLOCATIONTula Village is located along the southeast coast of the Island of Tutuila (Figure 2-1). The Tulawetland is located on the northwest side of Tula Village (Figure 2-2). Past studies suggest thatthe wetland comprises approximately 8 acres of land area (Biosystems Analysis, 1992). Morerecent studies by PPC indicate that the size of the wetland has now reduced to about 7.7 acres.WETLAND HYDROLOGYSources of Surface Runoff to the Tula WetlandIn a recent evaluation of potential stormwater management opportunities, Pedersen PlanningConsultants (PPC) noted the following surface water contributions to the Tula wetland.“The wetland receives surface runoff via overland flows from upland slopes south and west ofthe wetland. Along the north side of the wetland, two 4x8-foot culverts underneath the primaryshoreline roadway enable the transport of some runoff from upland slopes adjacent to thenortheast corner of the wetland” (Pedersen Planning Consultants, 2000).Field observations by PPC in May 1998 and November 1999 found no surface connectionsbetween Vailoa Stream, and/or the man-made swale through Tula Village, to the wetland. Thehydrologic connection between Vailoa Stream and the Tula wetland was thwarted by asomewhat higher stream elevation of Vailoa Stream upstream of a second set of two 4x8-footculverts that are underneath the primary shoreline roadway.At one time, Vailoa Stream was the primary source of surface runoff to the Tula wetland.However, more recent flooding and related discharges of sediment likely created a higherstream elevation. During re-construction of the primary shoreline roadway in 1994-1995, it isalso possible that some stream material, which was removed by contractors to install the two4x8-foot culverts, was conveniently placed upstream of the culverts to avoid hauling ofexcavated material to another site.Vailoa Stream also represents the hydrologic outlet for the Tula wetland. The two 4x8-footculverts underneath the primary shoreline roadway are capable of transporting stormwaterflows from both Vailoa Stream and the Tula wetland to the mouth of Vailoa Stream. However,the discharge of stormwater flows to the mouth of Vailoa Stream is hampered by higher streamelevations immediately upstream of the wetland, as well as the gradual filling of the Tulawetland.Stream Flows Along Vailoa StreamMedian Stream FlowsNine intermittent stream flow measurements between 1958 and 1965 were used, in part, by theU.S. Geological Survey (USGS) to estimate median stream flows along Vailoa Stream. In1996, USGS estimated that median stream flow was approximately 0.02 cubic feet per second(Wong, 1996).American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-1

Figure 2-1Location MapTula WetlandAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-2

Figure 2-2Tula WetlandExisting ConditionsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-3

Stormwater Discharges and Related Flood PotentialPedersen Planning Consultants made a hydrologic analysis of Vailoa Stream in 1998 todetermine the potential amount of stormwater that could be discharged into the Tula wetland.TABLE 2-1POTENTIAL STORMWATER DISCHARGES INTO TULA WETLAND2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 2-Year Storm 10-Year Storm 50-Year Storm 100-Year StormAll Surface Runoff 244 465 735 944Source: Pedersen Planning Consultants, 1998Through hydraulic modeling, PPC determined that potential stormwater discharges alongVailoa stream could range from 244 cubic feet per second (cfs) for a 2-year storm and about944 cfs for a 100-year storm.The areal extent of flood potential associated with an 11-year storm event was mapped by theFederal Emergency Management Agency (FEMA) in May 1991. When this information iscorrelated with digital building location data from the American Samoa GIS, it is clear that a100-year flood event would clearly impact most of the inhabited village area.In January 2000, representatives of the American Samoa Coastal Management Programobserved flooding in the vicinity of the Tula wetland and along the lower Vailoa Streamdrainage. This flooding was generated from a stormwater event that occurred January 20through January 22, 2000. Climatological data from the National Weather Service station atPago Pago International Airport recorded 6.41 inches of rainfall during this period. Availablerecords from NOAA’s Cape Matatula station near Tula Village indicate that the station madeno measurements during the January 20-22 period.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-4

Improved channelization of stormwater flows is needed to help reduce potential damages toresidential and commercial property in the village. Following higher rainfall events, surfacestormwater flows upland of the village has repeatedly spread over much of the upland portionof the inhabited village area. As a result, various homes in the upland village area have beenflooded. The capacity of the lower portion of Vailoa Stream is inadequate to accommodatelarger stormwater flows. The lower stream channel has likely been altered over the years toaccommodate gradual residential expansion in the upland village area. In addition, the presentblockage of the lower stream channel increases the areal extent of potential flooding andproperty damage resulting from a 100-year storm and less severe storm events.Construction of a second upland channel would help alleviate present flooding in the uplandarea and, at the same time, enable the transport of stormwater flows to the wetland. Onedesirable use of the Tula wetland would be stormwater detention. Restoration of this wetlandfunction would help reduce the amount of sedimentation that can be generated from VailoaStream. Stormwater detention would also permit the treatment and recharge of stormwater intothe fringe of the basal aquifer.WETLAND VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the Tula wetland on November 2and 17, 1999. Mr. Whistler was part of a three-person field survey team organized by PedersenPlanning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.West Side of Vailoa StreamVegetation observed within the Tula wetland along the west side of Vailoa Stream was notrepresentative of a wetland. Vegetation along the stream banks represented a mixture of typicalwetland or wetland margin plants such as Coix lacryma-jobi sanasana (Job’s tears), Paspalumconjugatum vao lima (T-grass), and more typical upland species such as Nephrolepis hirsutulavao tuaniu (sword fern). A few Hibiscus tiliaceus fau (beach hibiscus) and Barringtoniasamoensis falaga were also evident along the stream banks.Southwest of the Primary Shoreline RoadwayA fresh-water swamp dominated by beach hibiscus and a trough of highly disturbed marsh wasobserved southwest of a recent fill area. The fill area is immediately adjacent to the southwestside of the primary shoreline roadway.The highly disturbed marsh is situated in the northwest part of the wetland. The marsh isdominated by T-grass and somewhat less amounts of California grass and mauutoga(commelina). Considerably less amounts of weeds, such as Kyllinga nemoralis, tropicalcupgrass, Phyllanthus amarus, and three-flowered beggarweed were also evident in the marsh.All of the plants observed in this area represented introduced plant species. The only nativeherb recorded during the survey was selesele (Mariscus javanicus) that comprised only a fewclumps at the south end of the marsh.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-5

Vegetation TrendsTwo known botanical surveys have been made of the Tula wetland during the past 24 years.Whistler made a survey of the Tula wetland in 1976. Biosystems Analysis, Inc. surveyed thearea in 1991.Whistler concluded in 1976 that the area was a former coastal marsh. In 1991, BiosystemsAnalysis, Inc. later identified the Tula wetland as “...a ruderal freshwater wetland that ispredominantly an herbaceous marsh” (Biosystems Analysis, Inc., 1992).Aerial photographs from 1961 were reviewed by Biosystems Analysis, Inc. to calculatechanges in the size of the wetland. Biosystems Analysis concluded that the wetland at Tulawas “once dominated by trees and would have been characterized as a freshwater swamp.Much of the area has been cleared but it still supports freshwater herbaceous plants and small,scattered stands of trees and dead snags. The largest stand of trees occupies the upper(western) end of the wetland” (Biosystems Analysis, Inc., 1992).If the Tula wetland is not further disturbed, the beach hibiscus will probably continue to spreadfrom where it is already established to form a dense thicket. This thicket is expected to excludeall other tree and ground cover species. A similar condition already exists along the vehiculartrail that bisects through the west part of the Tula wetland. It is anticipated that the “take over’by beach hibiscus will be transient and only persist in areas that are disturbed (Steele, 2000).Should filling of the wetland continue, the Tula wetland will further decrease in size and likelybe replaced with homes, as well as banana and taro plantations. PPC has already observed theoccurrence of this trend on the east and west sides of the wetland between May 1998 andNovember 1999.AQUATIC FISH AND INVERTEBRATESDuring the November 2, 1999 survey, only a trickle of water was observed along VailoaStream, which is located on the east side of the Tula Wetland. The flow terminated in a pooland apparently seeped into the ground at that point. Despite the lack of stream flow, the streamchannel was blocked by larger boulders, debris, and vegetation. Such conditions preventedflow into the Tula wetland, as well as a downstream discharge to the stream mouth andadjoining nearshore waters.No marcrofaunal species were observed along the Vailoa Stream segment that adjoins the eastside of the Tula wetland. This condition was expected since upstream migration ofamphidronomous organisms was prevented by the blockage of Vailoa stream. However, onespecies of chironomid was found in low densities where there was flow.In American Samoa, each watershed is unique and can be expected to contain different aquaticorganisms. The variation depends upon surface water flow regimes, water quality, and othergeophysical characteristics. Consequently, if surface flows to the Tula wetland were notimpeded along Vailoa Stream, the wetland could possibly include some or all of the type ofaquatic animals summarized in Appendix B.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-6

LAND USES IN THE VICINITY OF TULA WETLANDThe Tula wetland has been impacted by land useswithin and immediately adjacent to the wetland.Landfills have been made within the northeast sideof the wetland. This area has been filled with acombination of dirt and cinder to facilitate somelimited agricultural production, and other structures.Immediately southwest of the fill area, aconsiderable amount of solid waste material hasbeen dumped within the wetland.Encroachment on the south, east and west sides ofthe wetland has also occurred. Landfill and relatedland use development have primarily established afew residences within the south and east sides of thewetland. Banana plantations and some limited taroproduction are also located on the south and westsides of the wetland.A local church is on the east side of the wetland.The congregation has also obtained authorizationfrom the American Samoa Coastal ManagementProgram after constructing a small recreational areaon the northwest site of the wetland. In order togain this authorization, ASCMP required the localchurch to mitigate their actions through therestoration of other parts of the Tula wetland.Several piggeries are located along the lower reaches of Vailoa Stream. Some of the piggeriesdischarge directly into Vailoa Stream and the Tula wetland.WETLAND RESTORATION AND ENHANCEMENT STRATEGIESGeneralThere are several potential opportunities for the restoration and enhancement of the Tulawetland. The scope of these six opportunities and related implementation strategies arepresented in the following paragraphs.The potential benefits and impacts derived from the implementation of each strategy aresubsequently compared and evaluated. This analysis provides the basis for the selection of arecommended restoration or enhancement strategy.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-7

Alternate Opportunities and StrategiesOption 1: Restore the Southern Part of Tula WetlandBiosystems Analysis, Inc. suggested in 1992 that the southern portion of the wetland could berestored to the amount of lands contained in the wetland in 1961. The ComprehensiveWetlands Management Plan described the potential scope of the restoration only in terms ofgeneral location. Today, a few homes are situated in the southern part of the wetland. Bananaplantations adjoin these residences.The restoration of the southern part of the Tula wetland would require the relocation of severalfamilies, residences and related banana plantations to other locations within Tula Village.Subsequently, fill material dumped within the wetland during the past 40 years would need tobe excavated and planted with native wetland tree species.Option 2: Establish a Stormwater Detention Area Within the WetlandThe development of a stormwater detention area within the Tula wetland (Figure 2-3) wasrecommended by PPC in a Stormwater Management Plan prepared for the Tula wetland andseveral other sites on the Island of Tutuila.The aim of the proposed conceptual design was to:• reduce flooding and potential property damage along the west side of Tula Village;• direct almost all stormwater flows from the Vailoa Stream drainage into the Tula wetland;• detain stormwater flows from stormwater events to permit the settlement of sedimentscarried by stormwater flows;• expand the size of the existing wetland and connect the wetland to the Vailoa Streamdrainage; and,• use Vailoa Stream as an outlet for stormwater discharges to the nearshore waters.To accomplish these objectives, PPC proposed the construction of a new earth-lined channelthat would be constructed on the west side of Tula Village. A 500-foot long channel wouldextend from the confluence of Vailoa Stream’s main stem and three tributaries to the Tulawetland. Basaltic rock will be used to line the channel at points where the potential for erosionis likely, e.g., inlets and outlets. Pre-fabricated concrete dissipators would be placed at selectedpoints along the channel to slow the rate of stream discharge.The existing wetland would be excavated and expanded to include an additional 1.0-acre on thenortheast side of the wetland. The expanded wetland would accommodate anticipated 100-yearstorm discharges. The wetland would be excavated to a depth of approximately three feetabove sea level. A nominal slope toward the east side of the wetland will be made to ensure aslower flow of stormwater to an existing culvert (T1) along Vailoa Stream that is situatedunderneath the primary shoreline roadway.A three-foot high wall would be constructed along the perimeter of the expanded wetland. Thewall would be constructed through the use of small bags of cement that would be hand-carriedand placed along the pond perimeter.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-8

Figure 2-3Option 2: Detention of Stormwater Within Tula WetlandAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-9

The wall would be back-filled with native soil to reduce the visual impact of the concrete bags,as well as afford the opportunity to plant ifi (Tahitian chestnut), other wetland trees, and somefruit trees. Approximately 50 wetland trees and 50 fruit trees would be planted immediatelyadjacent to the pond perimeter along a 20-foot wide buffer. Wetland and fruit trees wouldfurther enhance the attractiveness of the detention area and increase wetland vegetation in thevicinity of the wetland. Planting of the wetland and fruit trees would be the responsibility ofthe ASCC Land Grant Program.A culvert would also be installed within the southeast corner of the wall structure to enable thecollection and discharge of stream discharges from the existing man-made channel throughwest side of Tula Village. Existing culvert T1 would serve as the outlet from the detention areawhere overflows would discharge into the lower end of Vailoa Stream.Option 3: Expand Taro ProductionAnother wetland restoration opportunity is to expand taro production within a portion or all ofthe Tula wetland (Figure 2-4). The expansion of taro production would desirably beginsoutheast of existing production and gradually expand to the southeast part of the wetland.Water required from taro production would be derived from rainfall, as well as surface waterflows from Vailoa Stream.The portions of the wetland selected for taro production would initially require the excavationof fill material to a minimum soil depth of about one to two feet. Solid waste material andvegetative material contained in the remaining soil material will need to be removed from thesite. In terms of soil preparation, the production of talo toto i le vai (wetland taro) will requiremanual and/or mechanical tilling of the soil and the possible application of some limitednutrients to the soil.Taro cuttings from disease-free propagating material would be used to establish the taro. Thecuttings are part of a taro plant stem about 12 to 18 inches long that is attached to a 2 to 3-inchsection of the corm. Such cuttings would ideally be obtained from Western Samoa. Beforeplanting, selected taro cuttings should be carefully inspected, washed with potable water,soaked in a 10 percent bleach solution for 30 seconds, and stored in a dry, cool, and wellventilatedarea for 3 to 5 days before planting.Following larger stormwater events, detained stormwater in the wetland that exceeds what isrequired for taro production would require a hydrologic connection to Vailoa Stream and thenearshore waters. The restoration of the connection would require the excavation and gradingof some fill material and sediments along the bottom of, at least, the southeast side of thewetland to ensure the discharge of surface water to existing culverts below the primaryshoreline roadway. Surface flows from Vailoa Stream would also require some clearing ofdumped construction and fill materials that impede the discharge of flows into the Tula, as wellas the construction of an inlet structure along Vailoa Stream and the southeast side of thewetland.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-10

Figure 2-4Option 3: Expansion of Taro Production Within Tula WetlandAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-11

Option 4: Plant Wetland Trees to Augment Beach HibiscusThe Tula wetland could be enhanced through the planting of some wetland trees such as ifi(Tahitian chestnut), falaga, fuafua, and/or afa to augment beach hibiscus. Mango or other fruittrees, e.g., poumuli, could also be planted along the margins of the wetland. Tahitian chestnutwould be highly desirable since it is typically a freshwater swamp tree that produces nuts forconsumption by both humans and flying foxes.As stated earlier, vegetative trends suggest that the beach hibiscus will probably continue tospread from where it is already established to form a dense thicket. In the absence of anyresource management efforts, this thicket is expected to exclude all other tree and ground coverspecies. Consequently, the planting of recommended wetland trees would promote theestablishment of more wetland vegetation within the wetland.The tree planting efforts would logically be completed by the ASCC Land Grant Program.Land Grant personnel would need to propagate or obtain wetland tree seedlings and carry outthe planting of the seedlings within the wetland. In view of ongoing litigation, it would beprudent for Land Grant Program personnel to exclude local residents from tree planting effortsunless they request the opportunity to participate.Average rainfall in Tula Village will be adequate to support the growth of the recommendedwetland plants. However, the long-term survivability and growth of wetland plants within theTula wetland will depend upon the availability of fresh and/or brackish water and plant habitat.Re-establishment of a hydrologic connection with Vailoa Stream and the curtailment of furtherfilling of the wetland are required to initiate any serious efforts to promote conservation ofwetland plants.Option 5: Establish Habitat for Aquatic Fish and InvertebratesPotential opportunities for the re-colonization of aquatic fish and invertebrates may be possibleif the Vailoa Stream channel can be cleared of obstructions to restore the former hydrologicconnection between Vailoa Stream mouth and the Tula wetland. This wetland enhancementopportunity represents a potential benefit that may be achieved with restoration of thehydrologic connection between the wetland and the Vailoa Stream mouth.Option 6: Establish a Private Aquaculture OperationASCMP and ASEPA representatives suggested to PPC in June 2000 that a small aquacultureoperation could be established within a portion of the wetland. This concept would require theestablishment of a series of small channels within the wetland where selected fish and/orinvertebrate species could be raised and harvested. A technical feasibility study of this optionwould be required to assess the financial and technical viability of this development concept.Similar to other potential uses of the wetland, an aquaculture operation would again require therestoration of a hydrologic connection to Vailoa Stream. This connection would require theinstallation of an inlet structure, i.e., 36-inch diameter culvert, along Vailoa Stream, as well asgrading within the southeast part of the wetland to achieve a discharge of stormwater flows toexisting culverts underneath the primary shoreline roadway. This connection would berequired to avoid the flooding of aquaculture channels and related damage to onsite equipment.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-12

Comparative Benefits and ImpactsPPC’s evaluation of the six alternate restoration and enhancement strategies is summarized inTable 2-2. Three of the six opportunities, Options 2, 3, and 4, would achieve greater benefitsto natural resources and enhance opportunities for other potential wetland functions.Implementation of Option 2 would probably achieve a more desirable range of project benefits.The primary benefits would be increased stormwater detention within Tula Village, increasedgroundwater recharge, as well as reduction in future flood hazards and property damage.Secondarily, this option would clearly increase wetland vegetation along the margins of thewetland, as well as the two stream channels that would direct surface flows to the wetland. Theprimary consequence of Option 2 is the significant cost associated with project implementation.TABLE 2-2COMPARATIVE EVALUATIONWETLAND RESTORATION AND ENHANCEMENT OPPORTUNITIESTULA WETLANDOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetlandVegetationHabitatStormwaterDetentionFloodHazards &PropertyDamage1 SC SC SC NBC SB MB MB2 SC LC NBC LB MB SB SB3 MC LC SB LB LB LB MB4 LC LB LC LB SB LB LB5 MC LB LC MB LB LB LB6 MC LC LC LB LB LC LCNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsMB Moderate project benefitsLB Limited project benefitsNBC No anticipated project benefits or undesirable consequencesLC Limited undesirable consequencesMC Moderate undesirable consequencesSC Significant undesirable project impactsSource: Pedersen Planning Consultants, 2000Wetland taro production (Option 3) would generate desirable project benefits primarily throughthe enhancement of subsistence agricultural production. At the same time, the primary use ofthe wetland for taro production would limit the capacity of the wetland for future stormwaterdetention.The planting of wetland trees (Option 4) would enhance the establishment of wetlandvegetation within the wetland, but otherwise provide limited project benefits.Restoration of the south part of the wetland (Option 1) is not a promising opportunity. Therelocation of a several households and their residences in this area would not be well received.The American Samoa Government has brought a legal action against a prominent resident ofTula for the alleged fill of the wetland. There is no village rule or other cultural tradition thatprohibits the use of land within the Tula wetland (Pulou, 1999). Consequently, any ASGefforts aimed at planting wetland trees in an area presently used for residential purposes wouldlikely be unacceptable to the Tula Village Council and local residents.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-13

The establishment of fish and wildlife habitat (Option 5) provides significant benefits for fishand wildlife habitat with the restoration of a hydrologic connection between the wetland andthe mouth of Vailoa Stream. Otherwise, this option provides limited benefits.Recommended Option and Estimated Project CostThe development of a stormwater detention area within the Tula wetland, as well as relatedwetland tree plantings along the wetland margin (Option 2), is recommended forimplementation.While costly, this wetland enhancement project is attractive because the project can achievemultiple benefits to the Tula wetland and Tula Village.• increase stormwater detention;• reduce flood hazards within the west side of Tula Village;• increase groundwater recharge;• restore and expand wetland vegetation along the wetland margin; and,• establish some fish and invertebrate habitat through restoration of the hydrologicconnection between the wetland and Vailoa Stream.Construction of the proposed earth-lined channel and energy dissipators and detention pond isestimated to cost roughly $339,000 (Table 2-3). The planting of wetland and fruit trees wouldrequire an additional $2,571 (Table 2-4). Consequently, the total anticipated project cost wouldbe roughly $341,534.TABLE 2-3PRELIMINARY COST ESTIMATEDEVELOPMENT OF CHANNEL AND DETENTION PONDIN VAILOA STREAM DRAINAGE AND TULA WETLANDItem Unit Cost Quantity ExtensionMobilization Lump Sum 1 $ 5,000Excavation $5/Cubic Yard 5,000 25,000Channel Construction $50/LF 860 43,000Berm Construction $100/Linear Foot 1,850 185,000New Outlets $5,000/Each 3 15,000Culvert Along Vailoa Stream $325/LF 1 (30 feet) 9,750Clean Existing Culverts Lump Sum 1 2,000Road Crossings $5,000/Each 2 10,000Source: Pedersen Planning Consultants, 2000Subtotal $294,75015% Contingency 44,213TOTAL $338,963American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-14

TABLE 2-4PRELIMINARY COST ESTIMATEPLANTING OF WETLAND AND FRUIT TREES ALONG TULA WETLAND MARGINLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 8 8 64ASCC Field Crew Members 2 8 6 96All Personnel 4 120 $1,200MATERIALSItem Quantity Unit Cost ($) Cost ($)Wetland Trees 50 3 150Fruit Trees 50 5 250Garbage Bags 20 boxes 5 100All Materials $500EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $2,571Source: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the enhancement and restoration ofthe Tula wetland should include the seasonal monitoring of selected resource characteristicsand periodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-15

Long term monitoring of the Tula wetland restoration project will require periodicexaminations of:• changes in stream channel trapezoids;• potential stream modifications;• the benefits derived from restoration of the wetland stormwater detention function;• the survival of new wetland vegetation; and,• changes in adjoining land uses.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 2-5. A field work sheet or checklist, which can be used inthe field, is provided in Table 2-6.Future resource monitoring can be effectively performed through bi-annual site visits to theTula wetland and related stream channels. This approach will enable comparisons during wet(December through March) and dry (April through November) seasons of the year. Additionalvisits should also take place during and/or following significant stormwater events that may begenerated from periods of significant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.Recommended monitoring stations or sites (Figure 2-5) should be used consistently unlessunanticipated events, new land uses, or access issues prevent continued use. When necessary,changes in the location of monitoring stations should be documented and spatially locatedwithin the American Samoa GIS. PPC has provided digital files for the Wetland and StreamRestoration and Enhancement Plan that provide a departure point for future resourcemonitoring in the vicinity of the Tula wetland.Digital photos should also be dated and subsequently incorporated into the digital photo albumfor the Tula wetland. This will enable a long-term comparison of resource information by ASGstaff and consultants that may be used to perform long-term resource monitoring.Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents. Traditional leaders of the Tula VillageCouncil should be contacted before any long-term monitoring activities are initiated and carriedout.Site MaintenancePeriodic site maintenance should take place within the Tula wetland, lower Vailoa Stream, andthe proposed stream channel approximately four times per year. Human disposal of solidwastes within the wetland and the two stream channels is expected to represent the primaryfocus of long-term site maintenance.A crew of three to four persons will be necessary to walk the length of the two stream channelswithin the inhabited village area. Through the use of machetes and weed-eaters, the slopes ofboth earth-lined channels will require the periodic trimming of vegetation along selectedportions of the stream channels. The collection of solid wastes will also be necessary tominimize obstructions to stream flow and potential reductions in channel capacity.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-16

TABLE 2-5LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANTULA WETLANDResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Vailoa Stream: 700 feet upstream of wetland Presence of stream flow or obstructions to storm flowHydrology 1 x (April-Nov) Visual observation New channel: 400 feet upstream of wetlandWetland Outlet 1 x (Dec-March) Visual observation New outlet that will discharge into lower Presence of discharge from wetland into lower1 x (April-Nov) Visual observation Vailoa Stream Vailoa StreamStream Channel Stream channel 1 x (Dec-March) Measure manually, using tape measure Vailoa Stream: 700 feet upstream of wetland Changes in dimensions of stream channel trapezoidcross sections 1 x (April-Nov) at 100-foot intervalsNew channel: 400 feet upstream of wetlandat 100-foot intervalsStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually Vailoa Stream: 700 feet upstream of wetland Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, New channel: 400 feet upstream of wetland manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of wetland perimeter as well as Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, within 100 feet of Vailoa Stream and new discharges into wetland or stream channels?incorporate data into GIS stream channelsStormwater Restoration of 1 x (Dec-March) Take digital photos New water level post Water depth, in feetDetention Area stormwater 1 x (April-Nov) Document depth of water detentiondetention functionVegetation Survival of new 1 x (Dec-March) Take visual count of new plants 10 random stations around wetland perimeter Number of plants that remainvegetation 1 x (April-Nov)

TABLE 2-6FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANTULA WETLANDPAGE 1 OF 2 PAGESDate(s) of field monitoring:_______________ Name(s) of observer(s):Agency/Company Represented:Vailoa Stream New ChannelSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream? Yes No Yes No2a Are stream flows entering the wetland? Yes No Yes Nob If no, what appears to be impeding stream discharge? Describe.3 a Is the wetland outlet, e.g., culvert or stream mouth, clear to permit stream discharge? Yes No Yes Nob If not, what appears to be impeding flow to the wetland outlet? Describe.4 Observe and record water level post in wetland. feetSTREAM CHANNEL MODIFICATIONS5 a Has the stream bank been altered and with what material has the alteration been made? Yes No Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map _____ Check, when field map is so marked.6 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked7 a Is there evidence of bank erosion? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked8 a Do you see evidence of a change in the stream flow path? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID9 Refer to page 2: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW WETLAND PLANTS10 a Count number of surviving new wetland treesb Count number of surviving new fruit treesCHANGES IN LAND USE11 a Document type and number of new land uses within 100 feet of stream channels and wetland perimetersNumber of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked12 a Do any existing land uses, within 100 feet of the stream channel or wetland perimeter, appear to havesustained damage from past or recent stormwater events? Yes No Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNELS OR WETLAND13 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial14 Locate discharge on field map ___ Check, when field map is so marked

TABLE 2-6 (CONTINUED)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANTULA WETLANDCHANGES IN STREAM CHANNEL TRAPEZOID9 For each trapezoid represented below, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.Station Vailoa Stream New ChannelPAGE 2 OF 2 PAGES1+ 00 E EA B A BC D C DFF2 + 00 E EA B A BC D C DFF3 + 00 E EA B A BC D C DFF4 + 00 E EA B A BC D C DFF5 + 00 EABCFD6 + 00 EABCFD7 + 00 EABCFD

FIGURE 2-5RESOURCE MONITORING STATIONS AND AREASTULA WETLANDAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Tula Wetland, Page 2-20

Chapter ThreeALAO WETLANDLOCATIONAlao Village is located along the southeast coast of the Island of Tutuila and immediately southof Tula. There are two wetlands in Alao. The fresh-water wetland on the west side of AlaoVillage, or the smaller “Taufusi Marsh”, was evaluated for the Wetland Restoration andEnhancement Plan (Figure 3-1). Past studies suggest that the smaller Taufusi Marsh comprisesapproximately 5.6 acres of land area (Biosystems Analysis, 1992).WETLAND HYDROLOGYSources of Surface Runoff to the Taufusi MarshSurface runoff from Mulivaitele Stream drains into the Taufusi Marsh. The Mulivaitele Streamdrainage also includes surface runoff from Vaifusi Stream and Vaialili, which are tributaries toMulivaitele Stream. PPC confirmed these surface flow inputs to the Taufusi Marsh via onsiteobservations in November 1999. PPC also contacted a traditional village leader and anotherlocal resident who provided valuable information concerning past and recent hydrologicconditions.From the wetland, the main channel of Mulivaitele Stream serves as an outlet for the TaufusiMarsh. Stormwater flows are carried to a shoreline discharge point east of the primaryshoreline roadway (Figure 3-2). In November 1999, PPC observed no obstructions to streamflow. Signs of recent, continuous surface flow to the nearshore waters were also evident.Stream Flows Along Mulivaitele StreamMedian Stream FlowsIn 1996, the U.S. Geological Survey published estimated median stream flows from VaialiliStream and Vaifusi Stream. These estimates were based upon measurements gained from, twolow-flow, partial-record stations between 1958 and 1976, as well as related hydraulic modeling.One station along Vaialili Stream (No. 16965000) was situated approximately 0.2 mileupstream from the confluence with Vaifusi Stream. Data from 18 measurements enabled theU.S. Geological Survey to estimate a median flow of 0.08 cubic feet per second (cfs).A second station along Vaifusi Stream (No. 16966000), about 400 feet upstream of the streammouth, provided 17 measurements between 1958 and 1975. Data gained from thesemeasurements led the U.S. Geological Survey to estimate a median flow of 0.02 cfs (Wong,1996).American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-1

Figure 3-1Location MapAlao Village WetlandAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-2

Figure 3-2Taufusi MarchExisting ConditionsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-3

Stormwater Discharges and Related Flood PotentialPedersen Planning Consultants made a hydrologic analysis of Mulivaitele Stream to determinethe potential amount of stormwater that could be discharged into the Taufusi Marsh via a rangeof stormwater events (Table 3-1).TABLE 3-1POTENTIAL STORMWATER DISCHARGES INTO TAUFUSI MARSHFROM MULIVAITELE STREAM AND ITS TRIBUTARIES2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 2-Year Storm 10-Year Storm 50-Year Storm 100-Year StormMulivaitele Streamand all tributaries 238 393 701 813Source: Pedersen Planning Consultants, 2000Through hydrologic modeling, PPC determined that potential stormwater discharges alongMulivaitele stream can range from 238 cubic feet per second (cfs) for a 2-year storm and about813 cfs for a 100-year storm.During its November 1999 survey of the Taufusi Marsh, long-term residents informed the PPCsurvey team indicated that the village had previously experienced occasional flooding along thestream channel that serves as a hydrologic outlet from the wetland marsh to the nearshorewaters (Figure 3-2). However, the clearing of some obstructions within the Mulivaitele Streamchannel, which was accomplished by the American Samoa Power Authority in 1990, resolvedlocal flooding problems associated with smaller stormwater events, e.g., 2-year storm (Puaauli,1999).The potential flood plain associated with a 100-year storm event in Alao was mapped by theFederal Emergency Management Agency (FEMA) in May 1991. When this information iscorrelated with digital building location data from the American Samoa GIS, it is clear that a100-year flood event would clearly impact most of the inhabited village area (Figure 3-3).Given these prospects, it is important to conserve the Taufusi Marsh to promote continuedopportunities for stormwater detention. Otherwise, Alao Village may become more susceptibleto potential flood damages to residential and commercial property.WETLAND VEGETATIONNovember, 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the Taufusi Marsh on November2, 1999. Mr. Whistler was part of a three-person field survey team organized by PedersenPlanning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-4

Figure 3-3FEMA 100-Year Flood PlainAlao VillageAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-5

East Portion of the MarshThe east portion of Taufusi Marsh wasrecently cleared of vegetation for thecontinued production of Chinese cabbage.A network of man-made ditches andsmaller cultivated plots were constructedwithin this area to facilitate drainage.Immediately inland of this cleared areawas a moderate-sized area devoted to theproduction of bananas. A few olderpapaya trees and coconut trees were alsoobserved in this area; however, they werenot planted for any commercial production.West Portion of the MarshThe west portion of Taufusi Marshappeared to be an abandoned taro patchthat was dominated by a dense herbaceouscover of mauutoga (Commelina diffusa orcommelina). This portion of the marshalso contained considerably less amountsof primrose willow, fue sina (beach pea),and fue saina (mile-a-minute vine). Othertypical herbaceous wetland plants includedsansana (Job’s tears), fanamanu (Indianshot), Hibiscus abelmoschus, and Luffacylindrica along with scattered andovergrown individuals of talo (taro) thathave survived neglect.mauutoga (Commelina diffusa)The west end of the marsh was also characterized by some patches and scattered individuals ofthe shrubby laau failafa (candelabra plant) and some smaller fau (beach hibiscus) trees. Alongthe wetland margin, typical upland weeds such as Operculina turpethum, graceful spurge, andbeggar’s-tick replaced wetland vegetation. California grass, which is often common inwetlands, was also present.Vegetation TrendsBetween 1962 and 1964, several families in Alao planted talo (taro) in the Taufusi Marsh.Taro production in Taufusi Marsh continued until 1998. Families began harvesting poor tarocrops in the mid-1990’s as a result of lega (taro leaf blight) that adversely affected taroproduction in Alao and other production areas in American Samoa.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-6

East Portion of the MarshThe impact of the taro leaf blight led some families, who had title to communal lands in theMarsh, to begin production of Chinese cabbage in the east portion of the marsh. This crop isnow sold at the Fagatogo marketplace (Puaauli, 1999). Once the new blight-resistant cultivarsof taro become more readily available, taro production may once again be established within, atleast, the east portion of the Marsh.West Portion of the MarshIn 1992, Biosystems Analysis, Inc. observed taro cultivation along with willow primrose in theTaufusi marsh. It was also noted that soils in Taufusi Marsh “....drain slowly enough tosupport wetland plants”. With the more recent discontinuation of taro production, the westportion of the wetland transitioned to a disturbed marsh.It is likely that the west portion of the marsh will continue to be dominated by commelina.However, if the smaller hibiscus patches at the west end of the marsh continue to spread, thefau (Hibiscus tiliaceus) could possibly shade out the marsh vegetation and create a fresh-watermarsh dominated by fau (beach hibiscus).AQUATIC FISH AND INVERTEBRATESGeneralOn November 2, 1999, Charles Chong of the PPC field survey team made observations ofaquatic fish and invertebrates along a segment of Mulivaitele Stream from the east side ofTaufusi Marsh to approximately 380 feet upstream of the Mulivaitele Stream mouth. Hisobservations are summarized in the following paragraphs.The stream did not exhibit a stream discharge into the nearshore waters during the field survey.However, a nominal flow of less than 0.5 cubic feet per second (cfs) flowed downstream to apoint that was about 380 feet upstream of the shoreline. At this point, stream flows percolatedinto the bottom of the stream channel.Mulivaitele Stream Segment Along East Side of MarshThe fish and invertebrate survey focused upon the segment of the Mulivaitele Stream channelbetween the east side of Taufusi Marsh to approximately 380 feet upstream of the streammouth. The bed of the stream channel was characterized by cobble on top of clay soil. Therewas moderately heavy canopy above the stream. However, there was little or no periphytonalong this stream segment.The stream fauna contained an abundance of the fresh-water shrimp Macrobrachium lar that isknown to be amphidromous. Kuhlia rupestris was also abundant in larger pools. No gobies oranguillids were observed, although they have may have been present further upstream.Non-amphidromous species included the same chironoid larvae found in the Alao wetland.Many types of damselflies and dragonflies were also documented.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-7

In American Samoa, each watershed is unique and can be expected to contain different aquaticorganisms. The variation depends upon surface water flow regimes, water quality, and othergeophysical characteristics. With perennial, unimpeded stream flow to the ocean, the wetlandcould possibly include some or all of the type of aquatic animals summarized in Appendix B.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey is summarizedin Table 3-2. Genera are listed in order of descending abundance within their taxonomic group.TABLE 3-2SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED ALONG MULIVAITELE STREAMStream Location Fishes Crustaceans MolluscsFrom the east side of Taufusi Marshto approximately 380 feet upstreamof stream mouth.Source: Chong, 2000KuhliaMacrobrachium(2 spp.)NoneThe relative abundance and diversity of fish and invertebrates in Mulivaitele Stream, along theeast side of Taufusi Marsh, is summarized in Table 3-3. The relative abundance and diversityreflects a general comparison of the abundance and diversity of fish and invertebrates observedalong Mulivaitele Stream with all 10 sites evaluated for the Wetland Restoration andEnhancement Plan.TABLE 3-3RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESMULIVAITELE STREAM SEGMENT ON EAST SIDE OF TAUFUSI MARSHFishes Crustaceans MolluscsAbundance Medium High LowDiversity Low Low LowSource: Pedersen Planning Consultants, 2000LAND USES IN THE VICINITY OF TAUFUSI MARSHAs stated earlier, some production of Chinese cabbage was found in the east portion of theTaufusi Marsh. Other than a small shed, no other land uses were present in the marsh.The inhabited portion of Alao Village lies primarily east of Mulivai Stream. Only two to threeresidences are within about 500 feet of the marsh. Some limited subsistence bananaproduction, as well as a relatively large greenhouse used for cucumber production, weresituated immediately east of Mulivai Stream and the southeast side of Taufusi Marsh.Other areas that adjoin the north, south and west sides of the marsh remain undeveloped.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-8

WETLAND RESTORATION AND ENHANCEMENT STRATEGIESGeneralThere are two potential opportunities for the restoration and enhancement of Taufusi Marsh.The scope of these two opportunities and related implementation strategies are presented in thefollowing paragraphs.The potential benefits and impacts derived from the implementation of each strategy aresubsequently compared and evaluated. This analysis provides the basis for the selection of arecommended restoration or enhancement strategy.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Alternate Opportunities and StrategiesOption 1: Restore Native Marsh Vegetation and Wildlife HabitatThis option would attempt to restore native marsh vegetation in portions of the west part of theTaufusi Marsh. This restoration effort would be made through the planting of native marshplants such as utuutu (water chestnut), vao tuaniu (marsh fern), and saato (swamp fern).Plantings of seedlings or cuttings would be obtained by the ASCC Land Grant program andplanted by program personnel in selected portions of west Taufusi Marsh. However, it shouldbe noted that the feasibility of this option has not been tested through the propagation of theseplants in American Samoa or other parts of Polynesia (Whistler, 2000)Soil preparation will likely include the clearing and/or excavation of some areas where denseexotic vegetation is already established. Plant spacing and density would be determined by theASCC Land Grant Program prior to the initiation of planting.None of the recommended marsh plants were found in the marsh in November 1999 andprobably do not exist there. However, the establishment of these native marsh plants wouldenhance the attractiveness of this marsh to the toloa (Australian Gray Duck). This duck iswidespread in the South Pacific, but very rare in American Samoa. The habitat of theAustralian Gray Duck is typically fresh-water wetlands, but the duck is occasionally found inbrackish or salt water (Engbring and Ramsey, 1989). Occasional sightings of the AustralianGray Duck have been documented in the vicinity of nearby Maliuga Point (Aecos and AquaticFarms, 1980).Option 2: Restore Taro ProductionOption 2 (Figure 3-4) would restore taro production within the west portion of Taufusi Marsh.This potential restoration project would somewhat increase the capability of the marsh to detainstorm water. Increased detention would also promote greater recharge of surface runoff intothe basal aquifer.ASPA operates one groundwater well (well 161) and a related satellite water system in Alao.Well 161 produced approximately 12,000 gallons per day in May 2000. Consequently, thepotential benefits of increased groundwater recharge provide a feasible opportunity to conservepotable water supplies in Alao.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-9

FIGURE 3-4OPTION TWO: RESTORE TARO PRODUCTIONAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-10

The availability of new, blight-resistant cultivars of taro could enable future taro production inthe Taufusi Marsh. A project manager from the American Samoa Coastal ManagementProgram (ASCMP) would need to coordinate project tasks in cooperation with the AmericanSamoa Department of Agriculture and/or the Ministry of Agriculture in Western Samoa toobtain new varieties of taro that are resistant to the lega (taro blight).When obtained, a sample of such plants would be provided by the American Samoa CMP torepresentatives of families holding titles to lands within the marsh. The intent of this approachwould be to:• encourage family efforts to re-establish new varieties of wetland taro within the marsh, and• enable Alao residents to test the interest of Tutuila residents to purchase and consume thesenew varieties of taro.Implementation of this project would initially require the excavation of fill material in the westportion of Taufusi Marsh to a minimum soil depth of about one to two feet. Solid wastematerial and vegetative material contained in the remaining soil material will need to beremoved from the site. In terms of soil preparation, the production of talo toto i le vai (wetlandtaro) will require manual and/or mechanical tilling of the soil and the possible application ofsome limited nutrients to the soil.Taro cuttings from disease-free propagating material would be used to establish the taro. Thecuttings are part of a taro plant stem about 12 to 18 inches long that is attached to a 2 to 3-inchsection of the corm. Such cuttings would ideally be obtained from the ASG Department ofAgriculture or Samoa Ministry of Agriculture in Apia. Before planting, selected taro cuttingswould be carefully inspected, washed with potable water, soaked in a 10 percent bleachsolution for 30 seconds, and stored in a dry, cool, and well-ventilated area for 3 to 5 daysbefore planting.Comparative Benefits and ImpactsPPC’s evaluation of two alternate restoration and enhancement strategies is summarized inTable 3-4. One of these opportunities, Options 2, would achieve greater benefits to naturalresources and enhance opportunities for other potential wetland functions.An attempt to restore native marsh vegetation (Option 1) would require the planting of nativemarsh plants such as utuutu (water chestnut), vao tuaniu (marsh fern), and saato (swamp fern).None of these marsh plants were found in the marsh in November 1999 and probably do notexist there. However, cuttings could be obtained by the ASCC Land Grant Program andplanted by program staff.The prospect of community support for this restoration opportunity may be limited. At leastfour families in Alao Village hold titles to the lands comprising Taufusi Marsh (Puaauli, 2000).One or more families continue to be using the east portion of the wetland for the commercialproduction of Chinese cabbage that generates some household income.Wetland taro production would generate more desirable project benefits. Taro productionwould primarily enhance subsistence and commercial agricultural production, which isconsistent with other ongoing uses of the wetland. At the same time, taro production wouldsecondarily enhance future stormwater detention and generate some increased groundwaterrecharge to the basal aquifer.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-11

TABLE 3-4COMPARATIVE EVALUATIONWETLAND RESTORATION AND ENHANCEMENT OPPORTUNITIESALAO WETLANDOptionProjectCostResidentialLand UsesSubsistenceAgricultureWildlifeHabitatWetlandVegetationHabitatStormwaterDetentionFloodHazards &PropertyDamage1 LC NBC NBC SB SB LB NBC2 LC NBC SB LB LB MB LBNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsLC Limited undesirable consequencesMB Moderate project benefitsMC Moderate undesirable consequencesLBNBCLimited project benefitsNo anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000Recommended Option and Estimated Project CostSCSignificant undesirable project impactsThe restoration of taro production within the Taufusi Marsh (Option 2) is recommended forimplementation. This wetland enhancement project is recommended because the project can beachieved cost effectively, and at the same time, provide multiple benefits to Taufusi Marsh andAlao Village.From a resource management perspective, taro production will provide a combination ofbenefits that can be derived from increased stormwater detention and increased groundwaterrecharge. Alao Village may gain some nominal economic benefits from taro production thatcould generate some local employment and help sustain the economic viability of thecommunity. The restoration of taro production is complementary to other commercialagriculture production within the east side of the marsh.The costs associated with the restoration of taro production would be limited to the purchase ofwetland taro cuttings and the distribution of taro cuttings to Alao Village (Table 3-5).Otherwise, labor and equipment required for taro planting would be provided by local residentsof Alao. Total project costs are estimated to be $1,640.TABLE 3-5PRELIMINARY COST ESTIMATEPROCUREMENT AND DISTRIBUTION OF TARO PLANT CUTTINGSTO ALAO VILLAGELABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant NurseryTechnician 1 104 10 1,040All Personnel 1 104 $1,040MATERIALSItem Quantity Unit Cost ($) Cost ($)Taro Cuttings 100 5 500Garbage Bags 20 boxes 5 100All Materials $600EQUIPMENT (to be supplied by Alao Village)All Equipment $0TOTAL LABOR AND MATERIALS $1,640Source: Pedersen Planning Consultants, 2000American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-12

Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the enhancement and restoration ofthe Alao wetland should include the seasonal monitoring of selected resource characteristicsand periodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.Long term monitoring of the Alao wetland restoration and enhancement project will requireperiodic examinations of:• changes in stream channel trapezoids between the wetland and the Mulivaitele Streammouth;• potential stream modifications;• the survival of new taro plantings and taro production yields;• changes in adjoining land uses; and,• potential non-point source discharges into the wetland.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 3-6. A field work sheet or checklist, which can be used inthe field, is provided in Table 3-7.Future resource monitoring can be effectively performed through bi-annual site visits to theAlao wetland and lower Mulivaitele Stream channel. This approach will enable comparisonsduring wet (December through March) and dry (April through November) seasons of the year.Additional visits should also take place during and/or following significant stormwater eventsthat may be generated from periods of significant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-13

TABLE 3-6LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANALAO WETLANDResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Mulivaitele Sream: Immediately upstream of, Presence of stream flow or obstructions to stream flowHydrology 1 x (April-Nov) Visual observation along NE side of, and downstream of wetlandWetland Outlet 1 x (Dec-March) Visual observation Mouth of Mulivaitele Stream Presence of stream flow or obstructions to stream flow1 x (April-Nov) Visual observationStream Channel Stream channel 1 x (Dec-March) Measure manually, using tape measure Mulivaitele Stream: 1000 feet downstream of Changes in dimensions of stream channel trapezoidcross sections 1 x (April-Nov) wetland at 100-foot intervalsStream Changes to 1 x (Dec-March) Take digital photos, measure manually Mulivaitele Stream: 1000 feet downstream of Evidence of bank erosion, changes in flow path, or newModifications stream banks 1 x (April-Nov) using tape measure, record type & size, wetland manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new taro plants Where taro plantings are made Number of taro plants that remain; production yieldstaro plants 1 x (April-Nov)Water Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of wetland perimeter as well as Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, within 100 feet of Mulivaitele Stream discharges into wetland or Mulivaitele Stream channels?incorporate data into GIS

TABLE 3-7FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANALAO WETLANDPAGE 1 OF 2 PAGESDate(s) of field monitoring:_______________ Name(s) of observer(s):Agency/Company Represented:Mulivaitele MulivaiteleStream StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream? Yes No Yes No2a Are stream flows entering the wetland? Yes No Yes Nob If no, what appears to be impeding stream discharge? Describe.3 a Is the wetland outlet, e.g., culvert or stream mouth, clear to permit stream discharge? Yes No Yes Nob If not, what appears to be impeding flow to the wetland outlet? Describe.STREAM CHANNEL MODIFICATIONS4 Has the stream bank been altered and with what material has the alteration been made? Yes No Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:5 If alteration has occurred, locate on field map _____ Check, when field map is so marked.6 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked7 a Is there evidence of bank erosion? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked8 a Do you see evidence of a change in the stream flow path? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID9 Refer to page 2: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW WETLAND PLANTS10 a Count number of surviving new taro plantsb Ask local resident to estimate annual production yield. PoundsCHANGES IN LAND USE11 a Document type and number of new land uses within 100 feet of stream channel and wetland perimeterNumber of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked12 a Do any existing land uses, within 100 feet of the stream channel or wetland perimeter, appear to havesustained damage from past or recent stormwater events? Yes No Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL OR WETLANDZ Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial14 Locate discharge on field map ___ Check, when field map is so marked

TABLE 3-7FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANALAO WETLANDPAGE 1 OF 2 PAGESDate(s) of field monitoring:_______________ Name(s) of observer(s):Agency/Company Represented:Mulivaitele MulivaiteleStream StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream? Yes No Yes No2a Are stream flows entering the wetland? Yes No Yes Nob If no, what appears to be impeding stream discharge? Describe.3 a Is the wetland outlet, e.g., culvert or stream mouth, clear to permit stream discharge? Yes No Yes Nob If not, what appears to be impeding flow to the wetland outlet? Describe.STREAM CHANNEL MODIFICATIONS4 Has the stream bank been altered and with what material has the alteration been made? Yes No Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:5 If alteration has occurred, locate on field map _____ Check, when field map is so marked.6 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked7 a Is there evidence of bank erosion? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked8 a Do you see evidence of a change in the stream flow path? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID9 Refer to page 2: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW WETLAND PLANTS10 a Count number of surviving new taro plantsb Ask local resident to estimate annual production yield. PoundsCHANGES IN LAND USE11 a Document type and number of new land uses within 100 feet of stream channel and wetland perimeterNumber of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked12 a Do any existing land uses, within 100 feet of the stream channel or wetland perimeter, appear to havesustained damage from past or recent stormwater events? Yes No Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL OR WETLANDZ Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial14 Locate discharge on field map ___ Check, when field map is so marked

Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS. PPC has provided digital files for the Wetland and Stream Restorationand Enhancement Plan that provide a departure point for future resource monitoring in thevicinity of the Alao wetland.Digital photos should also be dated and subsequently incorporated into the digital photo albumfor the Alao fresh-water wetland. This will enable a long-term comparison of resourceinformation by ASG staff and consultants that may be used to perform long-term resourcemonitoring.Digital photos of taro production should also be supplemented with documentation of actualproduction yields from local residents. This information should be documented within acomputer spreadsheet that would be established for production data. This information wouldfacilitate future evaluations of taro production.Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents. Traditional leaders of the Alao VillageCouncil should be contacted before any long-term monitoring activities are initiated and carriedout.Site MaintenancePeriodic site maintenance should take place within the Alao fresh-water wetland and lowerMulivaitele Stream approximately four times per year. Human disposal of solid wastes withinthe wetland and the Mulivaitele Stream channel is expected to represent the primary focus oflong-term site maintenance.A crew of three to four persons will be necessary to walk the length of the lower MulivaiteleStream channel within the inhabited village area. Through the use of machetes and weedeaters,the portions of the Mulivaitele Stream channel will require the periodic trimming ofvegetation. The collection of solid wastes will also be necessary to minimize obstructions tostream flow and potential reductions in channel capacity.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Alao Wetland, Page 3-17

Chapter FourAOA WETLANDLOCATIONAoa Village is located along the northeast coast of the Island of Tutuila. There is one largewetland in Aoa that comprises roughly 23.5 acres of land area (Figure 4-1). The Aoa wetlandincludes a combination of fresh-water swamp, fresh-water marsh, and swamp forest.WETLAND HYDROLOGYSources of Surface Runoff to the Aoa WetlandThe primary source of water in the wetland is surface runoff from Tapua Stream and PunaStream (Figure 4-2). Tapua Stream receives drainage from its upland tributary, Lepa Stream,and generally flows south to north through the middle of the wetland before discharging intothe nearshore waters. Puna Stream, which originates near the 400-foot contour, transportsrunoff from the west side of Olomoana Mountain through the northeast side of the wetland.Available topographic maps for Aoa Village suggest a contribution of runoff from VaitoluStream to the Aoa wetland. Field observations by PPC in November 1999 indicate that thelower channel may have been modified by local residents to:• help reduce potential flood damages to residential property; and/or,• accommodate past residential development on the southwest side of the wetland.Stream flows presently discharge directly to Aoa Bay in the Vaiaga area. PPC believes thatVaitolu Stream may have formerly discharged into Aoa wetland.A smaller portion of the runoff discharged into the wetland is also received directly from viasteeper, upland slopes on the south side of the wetland.Stream FlowsMedian Stream FlowsIn 1996, the U.S. Geological Survey published an estimated median stream flow for LepaStream (Figure 4-1). The median stream flow estimate was based upon historical stream flowmeasurements obtained from a low-flow, partial-record station between 1958 and 1975, as wellas related hydraulic modeling (Table 4-1).TABLE 4-1MEDIAN STREAM FLOW ESTIMATELEPA STREAMStreamUSGSGage StationGage LocationLepa Stream 16905000 0.5 mile upstream fromTapua Stream mouthSource: Wong, 1996Stream FlowMeasure-ments(number)EstimatedMedian Flow(cfs)22 0.11American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-1

Figure 4-1Location MapAoa Village WetlandAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-2

Figure 4-2Aoa WetlandExisting ConditionsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-3

No stream flow estimates are available for Puna Stream. However, former Aoa resident andprincipal of Olomoana Elementary School informed Pedersen Planning Consultants in 1996that Puna Stream flows intermittently. PPC found no evidence of stream flow during theNovember 1999 survey.Stormwater Discharges and Related Flood PotentialPedersen Planning Consultants made a hydrologic analysis of the potential stormwaterdischarges to Aoa wetland during a range of storm events.TABLE 4-2POTENTIAL STORMWATER DISCHARGES INTO AOA WETLANDFROM TAPUA AND PUNA STREAMS2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 2-Year Storm 10-Year Storm 50-Year Storm 100-Year StormTapua-Lepa StreamDrainage 455 725 1,228 1,392Puna Stream 55 95 180 215All Streams 510 820 1,408 1,607Source: Pedersen Planning Consultants, 2000Through hydrologic modeling, PPC determined that potential stormwater discharges into theAoa wetland can range from 510 cubic feet per second (cfs) for a 2-year storm and about 1,607cfs for a 100-year storm.During PPC’s November 1999 survey, a 17-year resident of Aoa informed the survey team thatabout four homes on the southeast side of the wetland are flooded about once a year. Moist soiland water typically enter this area during the rainy season (Afusia, 1999). PPC representativesobserved similar flooding and moist soil conditions during its survey of the village in May1996 for the American Samoa Watershed Protection Plan.The potential flood plain associated with a 100-year storm event in Aoa was mapped by theFederal Emergency Management Agency (FEMA) in May 1991. Available flood insurancerate maps prepared by FEMA suggest that all inland village areas south of the Aoa Bayshoreline have limited flood potential.However, continued landfill in the southeast part of the Aoa wetland for residential purposeswill only decrease the capability of the wetland to detain stormwater. Future residentialexpansion will likely exacerbate flooding problems and generate more future property damagesin the southeast part of the wetland. PPC representatives discussed this issue with the villagepulenuu, who is also a matai, during the November 1999 survey. The matai/pulenuu indicatedthat he would discuss the flooding problems and future stormwater detention needs with othermembers of the Aoa Village council (Taase, 1999).American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-4

Hydrologic Outlet to Aoa BayThe mouths of Tapua Stream and Puna Stream represent the hydrologic outlets to the Aoawetland. Two sets of culverts are situated below a shoreline vehicular trail on the northeastside of Olomoana School.A set of two 12-foot wide x 5-foot highculverts are located immediately adjacent to thenortheast side of Olomoana Elementary School.These culverts were apparently constructed toaccommodate drainage from Tapua Stream.Roughly 100 feet east of these culverts lies anolder and smaller 12-foot wide x 3.5-foot highculvert that should accommodate flows fromPuna Stream. This culvert probably carried thecombined drainage from Puna and TapuaStream before construction of the two newerculverts.In November 1999, Pedersen Planning Consultants (PPC) observed that surface flows from thewetland to the newer culverts were completely clear and a nominal stream flow of less than 0.5cfs was evident. In contrast, potential stream flow through the older culvert was blocked bydebris, vegetation, and sand on the seaward side of this outlet.During the survey of the Aoa wetland, PPC’s three-person field survey team was accompaniedby Mr. Colin Steele, ASCC/AHNR project forester. Mr. Steele observed during the survey thatthe blockage of one of the two sets of culverts and related loss of tidal exchange had impactedthe health of mangrove plants on the northeast side of the Tapua Stream mouth. The blockedstormwater culvert at the mouth of Puna Stream may have been blocked during earlier villageroad construction.In the aftermath of Hurricane Val in 1991, the mouths of Tapua Stream and Puna Streamapparently became clogged with garbage, rocks and soil material. Standing salt water changedwater quality just inland of the stream mouth and culverts. The change in water qualityapparently caused a die-off of many mangrove trees along the northeast side of the TapuaStream (Steele, 1999).WETLAND VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the Aoa wetland on November 3and 17, 1999. Mr. Whistler was part of a three-person field survey team organized by PedersenPlanning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-5

Fresh-Water SwampThe fresh-water swamp was strongly dominated by fau (beach hibiscus). The spreadingbranches of the beach hibiscus occasionally formed thickets that impeded access through them.Ifi (Tahitian chestnut) was also common.Other trees such as leva (coconuts), aoa (Samoan banyans), falaga (Barringtonia samoensis),milo (Pacific rosewood), poumuli (Fluggea flexuosa), gatae (coral tree), laupata (Macarangaharveyanna), and laufala (screwpine) were observed in smaller numbers. With the exception ofpoumuli, all of these trees are native to American Samoa.Smaller numbers of oriental togo (mangrove) were present near the mouth of Tapua Stream. Asstated earlier, the health of some of these species has been affected by the loss of regular tidalexchange, higher concentrations of salt water, and related changes in the water quality of theswamp.The understory of the fresh-water swamp was muddy and contained little groundcover. Thespecies present have to contend with low light conditions and constant muddy soils.The most common plant species were seedlings and saplings of ifi (Tahitian chestnut), as wellas some other species such as nonu (Indian mulberry), auauli (Samoan ebony), filimotomafatifati (Geniostoma rupestre), mosooi (Cananga odorata), oa (Bischofia javanica), as wellas a few stunted banana trees. Saato (swamp fern) formed clumps in a few locations,particularly in more sunny areas. In standing water, the weed Struchium sparganophorum wascommon.Various epiphytes were common on tree trunks and stumps. These plants included variousspecies such as:• the ferns Pyrrosia lanceolata, laugasese (Davallia epiphylla) and laugasese (Davalliasolida);• laugapapa (bird’s nest fern)and lau magamaga (Phymatosorus grossus);• vines such as lau mafiafia (wax flower); and,• mati (the epiphytic tree or shrub dyer’s fig).Fresh-Water MarshesTwo marsh areas are located in the Aoa wetland.One marsh area is situated south and west of Olomoana School. Most of this marsh containedstanding water. The downstream portion of this marsh was dominated by harveyana (salt grass)that formed dense patches. Further inland, away from the influence of seawater, the marsh isdominated by mauutoga (commelina). The commelina is mixed with smaller amounts ofutuutu (water chestnut), selesele (Mariscus javanicus), another selesele (Rhynchosporacorymbosa), willow primrose, sanasana (Job’s tears), and swamp fern. At its southwest end,the commelina is entirely replaced by a dense combination of willow primrose and fue saina(mile-a-minute weed). The southwest end contained a banana plantation.A second marsh was located at the base of upland slopes along the southeast side of thewetland. Subsistence agricultural plantations were located on the east and west sides of themarsh. This area was formerly a taro plantation that was abandoned. This marsh wasAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-6

dominated by willow primrose along with patches of beach hibiscus, mile-a-minute vine, andJob’s tears.Swamp ForestA swamp forest was located along edges of the standing water and marshes, e.g., around themarsh south and west of Olomoana School. Swamp forest also extended inland to near thebase of upland slopes on the south side of the Aoa wetland.Most of the swamp forest was characterized by beach hibiscus without the presence of littoralspecies such as mangrove or Pacific rosewood. Smaller banana plantations and housesreplaced the fresh-water swamp along its inland margins.Vegetation TrendsDecline of Former Mangrove ForestSignificant changes have occurred in the vegetation of the Aoa wetland since 1976. Some fouracres of mangrove were observed in 1976. In 1991, Biosystems Analysis, Inc. observed orientalmangrove, red mangrove, and beach hibiscus in the fresh-water swamp. During the November1999 survey, the remnants of the former mangrove forest represented only scattered mangrovetrees along the margins of the fresh-water swamp. Consequently, mangrove trees may benaturally dying and/or some residents may be harvesting mangrove trees for firewood or otherpurposes. In either case, domination of the fresh-water swamp by beach hibiscus and Tahitianchestnut can be expected to continue in areas that are not changed by landfills for residentialdevelopment and agricultural plantations.Changing Characteristics of the Fresh-Water MarshThe fresh-water marsh south of Olomoana School exhibited all the appearances of having beena former taro patch since it was dominated by commelina in November 1999. Following theabandonment of a taro plantation, the domination by commelina usually follows. However,this area did not appear to be a habitat where taro is typically grown, e.g., close to the ocean.Former surveys by both Whistler in 1976 and Biosystems Analysis, Inc. in 1991 did notidentify the presence of taro in this location.It is anticipated that patches of water chestnut will eventually spread over the entiredownstream area if it can out compete the typically weedy commelina. Such a trend willrequire the lack of disturbance, e.g., cultivation of taro, in the fresh-water marsh. It is unusualthat California grass, which dominated this area in 1991, was not present in November 1999. Iftrue, the California grass was replaced by commelina, due possibly to some change in habitatfactors.The disturbed marsh on the southeast side of the Aoa wetland was also quite different than thatpreviously described by Biosystems Analysis, Inc. in 1992. Biosystems Analysis, Inc. noted“.....scattered patches of beach hibiscus with an herbaceous layer of grasses”. As stated earlier,PPC observed that the marsh was dominated by willow primrose along with patches of beachhibiscus, mile-a-minute vine, and Job’s tears in November 1999. One or more of these speciesmay dominate for a long time. However, native plants such as water chestnut may invade andAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-7

ecome dominant if there is a nearby seed source since this plant is presently absent from themarsh.AQUATIC FISH AND INVERTEBRATESGeneralOn November 3, 1999, Charles Chong of the PPCfield survey team made observations of aquatic fishand invertebrates along portions of Tapua Stream andits upland tributary, Lepa Stream. His observationsare summarized in the following paragraphs.Aoa wetland contained a small estuary just upstreamof the Tapua Stream mouth. The estuary was fed bysurface runoff from Tapua Stream and Lepa Stream.Puna Stream was completely dry during theNovember 3 survey; no flows were observed at itsconfluence with Tapua Stream.Lepa StreamTapua Stream was also dry for a short distancebetween Aoa wetland the base of upland slopes onthe south side of the wetland. The stream flowthrough one set of culverts just upstream of the TapuaStream mouth was less than 0.5 cfs during the survey.FishSmall estuary upstream of Tapua Stream mouthThe estuary inside Aoa wetland and inland portion of Tapua Stream contained nearly all of thefresh-water fishes known to American Samoa. Within the estuary, Mugil and Kuhlia spp. wereabundant as were other euryhaline fishes such as Periopthalmus.The amphidromous gobioids, Stenogobius genivittatus and Eleotris spp., as well as fresh-waterspecies Poecilia reticulata and P. mexicana, were common in the estuary. Other gobies,however, were not seen anywhere in the wetland. Lower stream flow and intermittent streamflow conditions may have prevented the presence of other gobies.A few residents informed Charles Chong of the PPC survey team that anguillids were presentin the upper reaches of Tapua Stream. Captive specimens, obtained by local residents,evidenced their presence in the stream. However, Chong observed no anguillids during thefield survey.InvertebratesThe invertebrates observed in Tapua Stream and Lepa Stream included the completecompliment of fresh-water molluscs, but only a portion of the crustaceans known to AmericanSamoa. Immediately inland of the estuary, for example, two unidentified species of neritidsnails were abundant in Tapua Stream. Sisiwai and two other species were common. Alongupland Lepa Stream, only the larger smooth species of neritid snails was found.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-8

The crustacean fauna was dominated by Macrobrachium lar in the estuary as well as upstream.Two species of cariddean shrimp were found in lower densities upstream.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-9

Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey is summarizedin Table 4-3. Genera are listed in order of descending abundance within their taxonomic group.TABLE 4-3SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED WITHIN AOA WETLAND AND LEPA STREAMStream Location Fishes Crustaceans MolluscsTapua Stream lowland/estuaryKuhliaPoeciliaMugilPeriopthalmusStenogobiusEleotrisMacrobrachiumLepa Stream None CaradinaAtyaSource: Chong, 2000Neritina (2 spp.)ThiaraClithonNeritinaThiaraThe relative abundance and diversity of fish and invertebrates along the Tapua Streamlowland/estuary and upland Lepa Stream are summarized in Table 4-4. While the estuarycontain many species, the upper reaches of Lepa Stream had fewer species of fish and mollusksthan expected. The characterization of relative abundance and diversity reflects a generalcomparison of the abundance and diversity of fish and invertebrates observed along TapuaStream and Lepa Stream with all 10 sites evaluated for the Wetland Restoration andEnhancement Plan.TABLE 4-4RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESTAPUA STREAM AND LEPA STREAMFishes Crustaceans MolluscsAbundance Low Medium HighDiversity Medium Medium HighSource: Pedersen Planning Consultants, 2000LAND USES IN THE VICINITY OF AOA WETLANDOlomoana Elementary School is situated along the north side of wetland. A shoreline trailprovides vehicular pedestrian access between the primary Aoa village area and the neighboringVaiaga area.With the exception of one or two residences, thesouth side of the wetland generally remainedundeveloped as the base of upland slopes beginson the south side of Aoa wetland. However, thesoutheast portion of the Aoa wetland continued tobe used for considerably more house sites andsome subsistence agriculture. The filling of landsin the southeast part of the wetland will likelygenerate adverse consequences to Aoa Villagethrough increased flooding of the former marshand related property damages.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-10

Two ASPA groundwater wells (wells 151 and 152) and several residences are situated betweenthe east margin of the Aoa wetland and the primary roadway to Aoa Village. At least twovehicular trails along the east side of the wetland provide access from the primary roadway tolocal residences.Residential and subsistence agricultural activitiesalso are located on the west side of the wetland.One home near the mouth of Vaitolu Streamcontains a small man-made pool that is fed via afresh-water spring. The presence of Macrobrachiumlar, poeciliads, and prawn traps in thepool indicate that, at least, one family is usingaquatic organisms as a food resource.WETLAND RESTORATION AND ENHANCEMENT STRATEGIESGeneralThere are four potential opportunities for the restoration and enhancement of Aoa wetland.Three of these opportunities were originally identified by Biosystems Analysis, Inc. in theComprehensive Wetlands Management Plan. A fourth option identified by BiosystemsAnalysis was refined by PPC based upon discussions with representatives of the ASCC LandGrant Program. The scope of these restoration and enhancement opportunities and relatedimplementation strategies are presented in the following paragraphs.The potential benefits and impacts derived from the implementation of each strategy aresubsequently compared and evaluated. This analysis provides the basis for the selection of arecommended restoration or enhancement strategy.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Alternate Opportunities and StrategiesOption 1: Expand the West Boundary of the WetlandOption 1 would expand the west boundary of the Aoa wetland and establish a stream channelthrough the middle of a 100 to 200-foot wide strip of land. Through considerable excavationand grading along the middle reach of Vaitolu Stream, the new stream channel would be fedfrom surface flow via Vaitolu Stream.Option 2: Widen the Mouth of Vaitolu StreamOption 2 would widen the mouth of Vaitolu Stream and extend the restored area roughly 250feet inland of the stream mouth. Excavation would be required to gain tidal flow from thestream mouth, as well as accommodate the construction of a new 36-inch diameter culvert andnew bridge over the existing shoreline vehicular trail.Option 3: Establish a Fresh-Water Wetland Along Vaitolu Stream ChannelOption 3 would be similar to Option 2 with the widening of Vaitolu Stream. The primaryexception would be that tidal exchange from the nearshore waters would intentionally beblocked to establish a fresh-water wetland along the stream channel.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-11

Option 4: Restore Mangrove Forest Upstream of the Puna Stream and Tapua Stream MouthsRestoration of the mangrove forest immediately upstream of the Puna Stream and TapuaStream mouths (Figure 4-3) would initially require the clearing of sand, vegetation and solidwaste material that presently blocks tidal exchange via the Puna Stream mouth. This effort willrequire clearing within the existing 12-foot wide x 3.5-foot high culvert upstream of the Punastream mouth, as well as on the upstream and downstream sides of the culvert. A backhoe willalso be needed to facilitate the excavation of sand and heavier solid waste material.Machetes and weed-eaters can be used to mow vegetation upstream and downstream of theTapua Stream and Puna Stream culverts. Lighter, solid waste material should be burned.Excess material should be bagged in plastic garbage bags; arrangements should be made withASPA for a special collection of this material.In November 1999, the double culverts underneath the shoreline vehicular trail were clear ofany obstructions that might impede tidal exchange via the adjoining Tapua Stream mouth.Consequently, no clearing is anticipated at the Tapua Stream mouth or the upstream culvertunderneath the shoreline trail.The second task of the restoration effort would involve the planting of red and orientalmangrove trees within and along the margins of the estuary in the fresh-water swamp, as wellas the banks of Tapua Stream and Puna Stream between the culverts and the fresh-waterswamp.Roughly 50 red mangroves should be planted within the streambed because this plant readilycolonizes in estuaries and can sustain itself in waters with somewhat higher salt waterconcentrations (Stemmermann, 1981). Propagules or seedlings should be plantedapproximately three feet apart. Within three years, the mangroves should be thinned to about asix-foot spacing between each plant (Steele, 1999).In contrast, 25 oriental mangroves would more desirably be planted along the stream banksbecause it is less tolerant of salt water. Propagules or seedlings should again be spacedapproximately three feet apart. Plants should be thinned to a spacing of six feet within aboutthree years.Other smaller trees, shrubs and grasses that can survive successfully in a brackish, estuarineenvironment would supplement mangrove plantings. In-stream plantings of red mangrovewithin the estuary, for example, would be supplemented with approximately 25 fao trees (beachhibiscus). Along stream banks, the planting of oriental mangrove trees would be interspersedwith about 25 milo trees (Thesepesia populnea). Salt resistant grasses would be planted in theestuary to increase the amount of available habitat of fish upstream of the Tapua Stream andPuna Stream outlets.Comparative Benefits and ImpactsPPC’s evaluation of the four alternate restoration and enhancement strategies is summarized inTable 4-5. Option 4 would achieve significant benefits to wetland vegetation, reduce floodpotential in the vicinity of the Puna Stream mouth, expand a fish spawning area in the estuaryupstream of the Puna Stream mouth, and create new habitat for invertebrates. These potentialbenefits can be derived for considerably lower project costs.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-12

FIGURE 4-3OPTION 4: RESTORE MANGROVE FOREST UPSTREAM OF THE PUNA STREAMAND TAPUA STREAM MOUTHSAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-13

TABLE 4-5COMPARATIVE EVALUATIONWETLAND RESTORATION AND ENHANCEMENT OPPORTUNITIESAOA WETLANDOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetlandVegetationHabitatStormwaterDetentionFloodHazards &PropertyDamage1 SC SC MC LB SB LB LC2 SC MC LC SB SB NBC MC3 MC MC LC SB SB LB SC4 LC LC NBC SB SB NBC LBNotes:Potential project benefits were rated by PPC as follows:SB Significant project benefitsLC Limited undesirable consequencesMB Moderate project benefitsMC Moderate undesirable consequencesLBNBCLimited project benefitsNo anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000SCSignificant undesirable project impactsThe biggest risk associated with Option 4 is that frequent storm waves entering Aoa Bay willoccasionally transport sand that will partially or completely block future tidal exchange. In theabsence of regular tidal exchange, a significant change in the water quality of the estuary canadversely impact the health of mangroves. However, the same risk is associated with Option 2.While past encroachment has been made on the west side of the Aoa wetland, the potentialdevelopment costs associated with the implementation of options 1 and 3 appear unattractive inlight of limited to moderate benefits. Limited to moderate to significant disruptions in existingresidential land uses and subsistence agriculture would be generated by the development ofoptions 1,2 or 3. Such change would likely annoy most residents who would be directlyimpacted by the project. Further, there is a limited to moderate probability that options 1, 2 or3 would occasionally generate some flooding problems in the adjoining residential area.Significant benefits associated with the planting of red and oriental mangroves are anticipatedfrom options 2 and 3. The establishment of mangroves would desirably establish a coastalswamp forest and, at the same time, create new habitat for fish and invertebrates.Recommended Option and Estimated Project CostThe restoration of the mangrove forest immediately upstream of the Puna Stream and TapuaStream mouths (Option 4) is recommended for implementation. This wetland restorationproject is recommended because the project can provide multiple benefits to the Aoa wetlandand Aoa Village for considerably lower project costs.The costs associated with the restoration of the mangrove forest would primary be associatedwith the initial clearing of the Puna Stream mouth, as well as the subsequent collection andplanting of mangrove, fau, and milo tree cuttings by the ASCC Land Grant Program. Theseestimated cost associated with the initial clearing of the Puna Stream mouth would beapproximately $3,056 (Table 4-6). The planting of mangrove and riparian trees would requirean expenditure of approximately $2,721 (Table 4-7). Consequently, the total project wouldcost an estimated $5,777.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-14

TABLE 4-6PRELIMINARY COST ESTIMATEINITIAL CLEARING OF PUNA STREAM CULVERTLABORPersonnel Number Hours Hourly Rate ($) Cost ($)Supervisor 1 40 15 600Heavy Equip. Operator 1 40 13 520Laborer 2 40 6 480All Personnel 4 160 $1,600MATERIALSItem Quantity Unit Cost ($) Cost ($)Picks 3 15 45Sledge Hammers 3 25 75Shovel 3 22 66Weed-eaters 3 300 900Machetes 3 20 60Garbage Bags 32 boxes 5 160Wheel Barrows 3 50 150All Materials $1,456TOTAL LABOR AND MATERIALS $3,056Source: Pedersen Planning Consultants, 2000TABLE 4-7PRELIMINARY COST ESTIMATEPLANTING OF MANGROVE AND RIPARIAN TREESUPSTREAM OF TAPUA AND PUNA STREAM MOUTHSLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 8 8 64ASCC Field Crew Members 2 8 6 96All Personnel 4 128 1,200MATERIALSItem Quantity Unit Cost ($) Cost ($)Mangrove Propagules 75 5 375Riparian Trees 50 3 150Garbage Bags 25 boxes 5 125All Materials 650EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $2,721Source: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-15

Long-term resource management activities associated with the restoration of the Aoa wetlandshould include the seasonal monitoring of selected resource characteristics and periodic sitemaintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.Long term monitoring of the Aoa wetland restoration project will require periodic examinationsof:• General wetland/stream hydrology;• Stream channel modifications;• the survival of new mangrove propagules and riparian tree seedlings;• type and number of aquatic fish and invertebrates in the Tapua Stream estuary; and,• changes in adjoining land uses.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 4-8. A field work sheet or checklist, which can be used inthe field, is provided in Table 4-9.Future resource monitoring can be effectively performed through bi-annual site visits to theAoa wetland. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Aoa Village Council. Assuming thatresidents cooperatively permit periodic access for long-term resource monitoring, monitoringshould take place along the following two stream segments (Figure 4-4):TABLE 4-8American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-16

TABLE 4-8LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANAOA WETLANDResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Tapua Stream mouth to 300 feet upstream Presence of stream flow or obstructions to stream flowHydrology 1 x (April-Nov) Visual observation Puna Stream to 200 feet upstreamWetland Outlet 1 x (Dec-March) Visual observation Tapua Stream mouth Presence of stream flow or obstructions to stream flow1 x (April-Nov) Visual observation Puna Stream mouthWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Between Tapua and Puna Stream mouths and Do new land uses generate non-point surface or subsurfaceof Lower Alao Wetland uses 1 x (April-Nov) estimated size, locate changes on field Tapua Stream Estuary discharges into wetland or Mulivaitele Stream channels?mapVegetation Survival of new 1 x (Dec-March) Take visual count of new mangrove Between most downstream culverts of Tapua Number of trees that remaintrees 1 x (April-Nov) propagules and riparian tree seedlings and Puna Streams, and Tapua Stream EstuaryAquatic Fish Type and number 2 x (Dec-March) Collect driftnet samples of outgoing 100 feet upstream of Tapua Stream mouth. Changes in diversity and abundance of fish andand of fish and 2 x (April-Nov) larvae for 3-4 hour evening periods crustaceansInvertebrates crustaceans (see report narrative).Molluscs Type and number 2 nights (Dec-Mar) Mark-recapture technology or quadrant 100 feet upstream of Tapua Stream mouth. Changes in diversity and abundance of molluscsof molluscs 2 nights (Apr-Nov) counts at night.

TABLE 4-9FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANAOA WETLANDDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):Tapua Stream Puna StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream? Yes No Yes No2a Are stream flows entering the wetland? Yes No Yes Nob If no, what appears to be impeding stream discharge? Describe.3 a Is the wetland outlet, e.g., culvert or stream mouth, clear to permit stream discharge? Yes No Yes Nob If not, what appears to be impeding flow to the wetland outlet? Describe.STREAM CHANNEL MODIFICATIONS4 a Has the stream bank been altered and with what material has the alteration been made? Yes No Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map _____ Check, when field map is so marked.5 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Is there evidence of bank erosion? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked7 a Do you see evidence of a change in the stream flow path? Yes No Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedSURVIVAL OF NEW WETLAND AND RIPARIAN PLANTS8 a Count number of surviving new mangrove propagulesb Count number of surviving riparian tree seedlings.CHANGES IN LAND USE9 a Document type and number of new land uses within 100 feet of stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked10 a Do any existing land uses, within 100 feet of the stream channel or wetland perimeter, appear to havesustained damage from past or recent stormwater events? Yes No Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL OR WETLAND11 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial12 Locate discharge on field map ___ Check, when field map is so marked

FIGURE 4-4RESOURCE MONITORING AREASALAO WETLANDAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-19

• begin at the Tapua Stream mouth and continue 300 feet upstream of the stream mouth;• begin on the south side of the Puna Stream culvert, which is located underneath theshoreline vehicular trail connecting the east and west sides of Aoa Village, and continue200 feet upstream of the Puna Stream culvert.These monitoring areas should be used consistently unless unanticipated events, new land uses,or access issues prevent continued use. When necessary, changes in the location of monitoringstations should be documented and spatially located within the American Samoa GIS. PPC hasprovided digital files for the Wetland and Stream Restoration and Enhancement Plan thatprovide a departure point for locating the stream segments recommended for future resourcemonitoring.Digital photos should be dated and subsequently be incorporated into the digital photo albumfor the Aoa wetland. This will enable a long-term comparison of resource information by ASGstaff and/or consultants that may be used to perform long-term resource monitoring.More specific monitoring of stream fauna should be made at the lower end of the Tapua Streamestuary. The estuary generally extends between the Tapua Stream/Puna Stream confluence androughly 250 upstream of this confluence. Such monitoring should include the collection ofdriftnet samples of outgoing larvae, at least two times per month, for 3-4 hour evening periods.The driftnets (150-200 ųm mesh) should be attached to rebar pounded into the stream substrata,or simply suspended from trees or bridges to that the net is at the surface of the water. Thesamples would subsequently be preserved in ethanol. The type and number of fish andcrustaceans should be enumerated using a dissecting microscope. Use of the dissectingmicroscope will likely require a 2-3 day training class and the necessary equipment.Molluscs should be monitored in the lower part of the estuary by mark-recapture methodology,or quadrant counts at night since most are primarily nocturnal. Some training in thesetechniques is recommended.Site MaintenancePeriodic site maintenance should take place within the project area approximately four timesper year. Human disposal of solid wastes within the estuary and lower reaches of TapuaStream and Puna Stream is expected to represent the primary focus of long-term sitemaintenance. The periodic long-term maintenance of the Tapua Stream and Puna Streamculverts is necessary to ensure adequate tidal exchange and the maintenance of brackish waterquality.A crew of three to four persons will be necessary to periodically walk the length of the lowerchannels of Puna Stream and Tapua Stream, as well as related culverts immediately upstreamof the stream mouths. Such inspections would occur shortly after significant rainfall andstormwater events. Machetes and weed-eaters will be required to periodically trim vegetationalong selected portions of the stream channel. The manual collection of solid wastes will alsobe necessary to minimize obstructions to stream discharge and effective tidal exchange.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Aoa Wetland, Page 4-20

Chapter FiveVATIA WETLANDLOCATIONVatia Village is located along the north coast of the Island of Tutuila. One of two wetlands inVatia was examined for this investigation. This wetland is situated on the southeast side ofVatia Village (Figure 5-1).WETLAND HYDROLOGYSources of Surface Runoff to the Southeast WetlandThe primary source of water in the wetland is surface runoff from Faatafe Stream, Tufu Stream,and Mulivai Stream (Figure 5-2). These streams drain a portion of the northern slopes ofMaugaloa Ridge. This drainage area extends downslope between Tiatauala Ridge andMatavalu Ridge.Faatafe Stream originates near the 1,000-foot contour where it receives surface runoff from theeast side of Maugaloa Ridge. The stream course flows downslope through the west side of thewetland, meanders through a small residential area, and eventually discharges along the southside of Vatia Bay.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-1

Figure 5-1Location MapSoutheast Wetland in VatiaAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-2

Figure 5-2Southeast Wetland in VatiaExisting ConditionsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-3

Tufu Stream and two stream branches begin near the 1,200-foot elevation. Stream flows flowthrough the central part of the wetland. At about the 10-foot contour, Tufu Stream empties intoMulivai Stream along the east side of the wetland.Mulivai Stream originates approximately 1,200-feet above mean sea level. The main stem ofthe stream and a west branch merge near the 50-foot contour. These flows, as well asdownstream flows from Tufu Stream, eventually discharge at the mouth of Mulivai Stream.Stream FlowsMedian Stream FlowsNo historical stream flow records are available for Faatafe, Tufu, and Mulivai Stream.Stormwater Discharges and Related Flood PotentialPedersen Planning Consultants made a hydrologic analysis of potential stormwater dischargesto the southeast wetland in Vatia during a range of storm events. The computer modeling ofpotential stormwater events for a 2, 10, 50 and 100-year storm event suggest the generation ofstormwater flows that may range between 504 cubic feet per second (cfs) for a 2-year stormevent and 1,559 cfs for a 100-year storm.TABLE 5-1POTENTIAL STORMWATER DISCHARGESALONG SOUTHEAST SIDE OF VATIA BAY2,10,50 AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Stream 2-Year Storm 10-Year Storm 50-Year Storm 100-YearStormFaatafe Stream mouth 23 42 84 104Tufu/Mulivai Stream mouth 481 731 1,133 1,455All Streams 504 773 1,217 1,559Source: Pedersen Planning Consultants, 2000.The potential flood plain associated with a 100-year storm event was mapped by the FederalEmergency Management Agency (FEMA) in May 1991. Available flood insurance rate mapsprepared by FEMA suggest potential flooding downstream of the wetland. Such floodingwould likely occur:• up to 100 feet west of Faatafe Stream;• within the residential area east of Faatafe Stream to roughly 100 feet east of MulivaiStream.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-4

During a November 4, 1999 survey, the PPC survey team surveyed lower Faatafe Streambetween the north end of the wetland to the mouth of Faatafe Stream. Observations made byPPC during the survey suggest that the lower drainage course has been modified toaccommodate a recent expansion of the Mormon Church complex, as well as past residentialdevelopment along Faatafe Stream.The recent construction of a Methodistchurch east of the Mormon Churchcomplex has altered the stream course ofMulivai Stream. It is uncertain whether ornot this stream course modification andpossible fill prevented a stream dischargeat the mouth of Mulivai Stream. No flowwas observed along the lower end ofMulivai Stream during the survey. PPC wasadvised later by American Samoa CoastalManagement Program representatives thatan illegal fill of the wetland was underreview by the American Samoa Government(Mitchell, 1999).Southern boundary of Mormon Churchcomplex, adjacent to Faatafe StreamIf the hydrologic connection between lower Mulivai Stream has been blocked by recentwetland or stream fill activities, an increased stream discharge can be expected along FaatafeStream. In essence, an increased discharge along Faatafe Stream would only increase the floodpotential to residential properties along the east and west sides of this drainage.Hydrologic Outlet to Vatia BayAs stated earlier, the mouths of Faatafe Stream and Mulivai Stream represent the hydrologicoutlets from the southeast wetland of Vatia. Two sets of culverts are situated below a shorelinevehicular trail that is located along southeast side of Vatia Bay.A 17.5-foot wide x 5-foot high concrete culvert is located at the mouth of Faatafe Stream. Thisculvert is in good physical condition and is capable of accommodating stormwater flows from a50-year storm event.At the mouth of Mulivai Stream, there are three, 3-foot diameter culverts. These concreteculverts are in fair condition; however, they are undersized to handle stream flows from apotential 50-year stormwater event.WETLAND VEGETATIONNovember, 1999 SurveyOn November 4 and 17, 1999, Art Whistler of Isle Botanica conducted a botanical survey ofthe Faatafe Stream channel between the north end of the wetland and the Faatafe Streammouth. The lower stream segment extends approximately 850 feet southwest and southeast ofthe stream mouth.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-5

Mr. Whistler was part of a three-person field survey team organized by Pedersen PlanningConsultants that observed wetland vegetation, habitat for aquatic fish and invertebrates, streamhydrology, as well as land uses within and adjacent to the wetland. His observations aresummarized in the following paragraphs.Stream Mouth to Approximately 500 feet UpstreamThe lower portion of the Faatafe Streamchannel was highly disturbed. A rock wall,grassy area, and disturbed forest were situatedalong the first 300 feet of the west streambank. The forest along the east bank of thestream represented a mixture of scatteredfresh-water swamp, mangrove swamp, andlittoral forest trees such as coconut, togo(oriental mangrove), milo (Pacific rosewood),and fau (beach hibiscus).Further upstream, the stream channel widened before turning westward. An attractive, freshwaterswamp dominated by ifi (Tahitian chestnut) was situated in this area. Other species inthis location included one or a few individuals of oriental mangrove, coconut, laufala(screwpine), and a clump of ofe palagi (bamboo).Soils in this area were saturated and quite open since few plants could survive in this wet,shady habitat. The forest floor contained only seedlings of Tahitian chestnut, clumps of saato(swamp fern), and some falaga (Barringtonia samoensis) trees. Epiphytes were common on thetrees. More prominent epiphytes included the fern lau tasi (Pyrrosia lanceolata), laugasese(Davallia epiphylla), and laugapapa (bird’s nest fern).350 Upstream to North Side of WetlandAs the stream turned to the southeast, the vegetation changed significantly and revealed twoother types of wetlands.Swamp forest was observed along areas of standing or flowing water. This wetland wasdominated entirely by beach hibiscus. The dense tangle of branches and shaded canopyvirtually eliminated all other plant species except for some fue saina (mile-a-minute weed).Disturbed fresh-water marsh was found both downstream and upstream from the beach hibiscusforest. The marsh was dominated mostly by sanasana (Job’s tears). Lesser amounts of fuelautetele (Merremia peltata) are also evident in the marsh along with laau fai lafa (candelabra)plants.Along portions of this stream segment, the swamp forest and disturbed fresh-water marshappeared to merge. These locations were characterized by scattered individuals and clumps ofbeach hibiscus, coconut, and gatae palagi (dadap) trees.Job’s tears dominated underneath these trees. Lesser amounts of vao lima (T-grass), mile-aminuteweed, and losa honolulu (Honolulu rose) were also documented.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-6

Vegetation TrendsIn 1992, Biosystems Analysis, Inc. surveyed this wetland as part of its preparation of aComprehensive Wetlands Management Plan. Biosystems Analysis, Inc. recorded mangroves atthe mouth of Faatafe Stream and described the southeast wetland as a freshwater wetland withcoconut trees.The most significant change to the wetland has been a reduction in size. In 1992, BiosystemsAnalysis estimated that the southeast wetland comprised about 18.5 acres. Between 1992 and1999, about 2 to 3 acres have been lost by land fill activities associated with the developmentof the Mormon and Methodist church complexes.Taro cultivation was no longer present within the disturbed marsh in November 1999. Formertaro cultivation may have stopped due to the taro blight that occurred in the early 1990’s.A change in the mangrove forest, just upstream of the Faatafe Stream mouth, has occurredsince 1992. Biosystems noted the presence of both red and oriental mangrove. In November1999, only oriental mangrove was recorded. This lower stream area is now best classified as afreshwater swamp forest.AQUATIC FISH AND INVERTEBRATESGeneralOn November 4, 1999, Charles Chong of thePPC field survey team made observations ofaquatic fish and invertebrates along the lower850 feet of Faatafe Stream. His observationsare summarized in the following paragraphs.Just upstream of the stream mouth and mainshoreline roadway, there was a small estuarythat was fed by surface runoff from FaatafeStream, as well as a nearby spring. During thetime of the survey, stream flow was estimatedto be less than 1 cfs.FishFishes observed in the lower estuary possessed a high species diversity and abundance ofmacrofauna. Mugil, Chanos, Periopthalmus, Eleotris, Kuhlia and Stenogobius weredocumented within the estuary.Exotic Poecilia were abundant in the estuary and along the stream. Stiphodon, Anguilla, andKuhlia spp. were common at lower and higher stream elevation.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-7

InvertebratesCrustacean densities were high for Macrobrachium lar and Paleomon at lower and higherstream elevations. Caridina was common at higher stream elevations.Three neritids were present at lower elevations. However, the two largest species wererecorded at a higher stream elevation.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey is summarizedin Table 5-2. Genera are listed in order of descending abundance within their taxonomic group.TABLE 5-2SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED WITHIN VATIA WETLANDStream Location Fishes Crustaceans MolluscsFaatafe stream mouth to 330feet upstreamFaatafe Stream (about1,250-1,350 feet upstreamof stream mouthSource: Chong, 2000KuhliaPoecilia (2 spp.)MugilPeriopthalmusEleotrisSicyopterusAnguillaStenogobiusChanosKuhliaPoeciliaSicyopterusAnguillaMacrobrachiumPaleomonMacrobrachiumPaleomonCaradinaNeritina (3 spp.)Neritina (2 spp.)The relative abundance and diversity of fish and invertebrates observed within the Vatiawetland are summarized in Table 5-3. The characterization of relative abundance and diversityreflects a general comparison of the abundance and diversity of fish and invertebrates observedalong two segments of Faatafe Stream with all 10 sites evaluated for the Wetland Restorationand Enhancement Plan.TABLE 5-3RELATIVE ABUNDANCE AND DIVERSITY OF FISHAND INVERTEBRATES IN FAATAFE STREAMFishes Crustaceans MolluscsAbundance High High MediumDiversity High Medium HighSource: Pedersen Planning Consultants, 2000American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-8

The stream segment appeared to contain a healthy assemblage of stream macrofauna. Apotential increase in stream flow, which may have been generated from the filling of MulivaiStream, may actually enhance amphidromous specie populations by allowing perennialrecruitment into the stream.LAND USES WITHIN SOUTHEAST WETLAND AND FAATAFE STREAMThe north end of the wetland and lower Faatafe Stream segment is primarily interspersed withsingle family residential land uses. A comparison of 1990 aerial photography and onsiteconditions in November 1999 also suggest that two or three residential buildings have probablybeen built on the east side of the mangrove forest during the past decade.As stated earlier, Mormon and Methodist church complexes have been constructed within thewetland during the past 10 years. An expansion of the Mormon complex was nearingcompletion at the time of the November 1999 survey. The development of these facilities issignificant because site development carried out for both facilities reduced the size of thewetland and modified stream hydrology. The implications of potential stream alterations maybecome evident as larger stormwater events occur in the future.WETLAND RESTORATION AND ENHANCEMENT STRATEGIESGeneralThere are two practical opportunities for the restoration and enhancement of the Vatia wetlandand the lower reach of Faaatafe Stream. The scope of these restoration and enhancementopportunities and related implementation strategies are presented in the following paragraphs.The potential benefits and impacts derived from the implementation of each strategy aresubsequently compared and evaluated. This analysis provides the basis for the selection of arecommended restoration or enhancement strategy.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Alternate Opportunities and StrategiesOption 1: Restore Riparian Vegetation 450 Feet Upstream of Faatafe Stream MouthThe first phase of stream restoration would require the collection and disposal of a wide varietyof solid waste materials. Solid waste materials and garbage were discovered in the vicinity ofthe Faatafe Stream mouth, the roadway culvert underneath the shoreline roadway, and someportions of the upstream area. Manual collection will be sufficient to collect of this material.However, a larger dump truck may be required to haul larger materials to the Futiga landfill.Such equipment is available from either the American Samoa Power Authority or the AmericanSamoa Department of Public Works.The American Samoa Community College, Land Grant Program would subsequently initiatethe planting of more vegetation along the first 450 feet upstream of the Faatafe Stream mouth(Figure 5-3). Propagated seedlings of some native trees may already be available at the ASCCLand Grant Program nursery. Recommended plantings along this stream segment woulddesirably include, at least, the following:American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-9

FIGURE 5-3OPTION 1: RESTORE RIPARIAN VEGETATION 450 FEET UPSTREAM OFFAATAFE STREAM MOUTHAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-10

• 10 ateate (Wollastonia biflora) on the seaward side of the shoreline road culvert;• 50 togofafine (red mangroves) within the stream bed;• 25 fau (beach hibiscus) upstream of culvert between togofafine (red mangroves);• 25 ifi (Tahitian chestnut) and togo tane (oriental mangrove) along the stream bank; and,• 25 poumuli (Flueggea flexuosa) and fruit trees, e.g., mango, above the stream bank.The initial planting of mangroves should be approximately 3 feet apart. In-stream plantings ofred mangrove should be performed by ASCC Land Grant Program personnel. Within threeyears, red and oriental mangroves should be thinned to about a six-foot spacing between eachplant (Steele, 1999).The ASCC Land Grant Program would also encourage residents to participate in the planting ofthese trees along the east and west banks of the stream. ASCC Land Grant has considerableexperience with encouraging community participation through its Forestry StewardshipProgram. The enhancement of riparian vegetation and related participation of residents can bestbe accomplished by providing, at no charge, a total of about 30 tree seedlings to eachhousehold along the stream. However, the “no charge” arrangement would be conditional tothe resident’s agreement to plant the new trees within 30 feet of the stream bank (Steele, 1995).Option 2: Establish Wetland Vegetation AlongSouth Boundary of Mormon Church ComplexOption 2 would establish wetland vegetationalong the south boundary of the MormonChurch complex. Stream plantings along thisstream segment would promote long-termconservation of the wetland and FaatafeStream. This project would also help increasethe site’s bio-diversity, as well as provide asource of fruit for both humans and flyingfoxes.Plantings of ifi (Tahitian chestnut) and fuafua (Kleinhovia hospita) would be made along thesouth side of the Faatafe Stream that is immediately south of the Mormon Church complex.The plantings should extend for, at least, 150 feet along this stream segment.If desired by one or more households west of the Mormon Church complex, similar plantingswetland vegetation could continue for up to another 250 feet. The potential extension of thisproject, however, would clearly require the authorization of these residents.Comparative Benefits and ImpactsPPC’s evaluation of the two alternate restoration and enhancement strategies is summarized inTable 5-4. Option 1 would restore mangrove vegetation and provide significant improvementsto wetland vegetation for a reasonable cost. Restoration of the mangrove vegetation along thelower reach of Faatafe Stream would also enhance the attractiveness of adjoining residentialarea.Option 2 could also be developed for a reasonable cost. This option would also providesignificant improvements to wetland vegetation and help deter further encroachment into thewetland.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-11

TABLE 5-4COMPARATIVE EVALUATIONWETLAND RESTORATION AND ENHANCEMENT OPPORTUNITIESVATIA WETLANDOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetland/RiparianVegetationStreamBankStabilityFlood Hazards& PropertyDamage1 LC MB NBC LB SB MB NBC2 LC NBC NBC LB SB MB NBCNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsLC Limited undesirable consequencesMB Moderate project benefitsMC Moderate undesirable consequencesLB Limited project benefitsSC Significant undesirable project impactsNBC No anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000Recommended Option and Estimated Project CostThe restoration of the mangrove forest immediately upstream of the Faatafe Stream mouth(Option 1) is recommended for implementation. This wetland restoration project isrecommended because the project can provide significant improvements to wetland vegetation,enhance the adjoining residential area, and provide a source of food to humans and flyingfoxes.The costs associated with the restoration of the mangrove forest would primary be associatedwith the initial clearing of the Faatafe Stream mouth, culvert underneath the shoreline roadway,as well as the collection of some trash and solid waste material 450 feet upstream. Thesubsequent collection and planting of mangrove, fau, and milo tree cuttings would be carriedout by the ASCC Land Grant Program.These estimated cost associated with the initial clearing of the Faatafe Stream mouth, roadwayculvert and upstream area would be approximately $2,996 (Table 5-5). The propagation of treeseedlings, the collection of tree cuttings, as well as the planting of recommended vegetationwould cost an estimated $2,811 (Table 5-6). Consequently, overall project expenditures wouldcost an estimated $5,807.TABLE 5-5PRELIMINARY COST ESTIMATECLEARING OF FAATAFE STREAM MOUTH, CULVERT, AND UPSTREAM AREALABORPersonnel Number Hours Hourly Rate ($) Cost ($)SupervisorHeavy Equip. Operator1140401513600520Laborer 2 40 6 480All Personnel 4 160 $1,600MATERIALSItem Quantity Unit Cost ($) Cost ($)PicksSledge Hammers3115254525Shovel 3 22 66Weed-eaters 3 300 900MachetesGarbage Bags320 boxes20560100Wheel BarrowsAll Materials3 50 150$1,346TOTAL LABOR AND MATERIALS $2,946American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-12

Notes: Preliminary estimate assumes use of existing equipment owned by ASG Department of Public WorksSource: Pedersen Planning Consultants, 2000TABLE 5-6PRELIMINARY COST ESTIMATEPLANTING OF MANGROVE AND RIPARIAN TREESUPSTREAM OF FAATAFE STREAM MOUTHLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 10 8 80ASCC Field Crew Members 2 10 6 120All Personnel 4 134 $1,240MATERIALSItem Quantity Unit Cost ($) Cost ($)Mangrove Propagules/Seedlings 50 5 250Riparian Trees 50 3 150Fruit Trees 25 5 125Coastal Plants 10 5 50Garbage Bags 25 boxes 5 125All Materials $700EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $2,811Source: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the Vatia wetland restoration, alongthe lower reach of Faatafe Stream, should include the seasonal monitoring of selected resourcecharacteristics and periodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-13

Long term monitoring of the Vatia wetland restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of stream flow;• potential impedances to stream discharge;• potential changes in the flow path of Faatafe Stream;• evidence of eroding stream bank areas;• potential failures or damages to gabion baskets or rock walls along the stream bank;• survival of planted, riparian and wetland vegetation;• potential flood damages to residential properties;• changes in land uses immediately adjacent to the stream banks;• point-source discharges, e.g., wastewater from piggeries; and,• changes in the type and number of fish and invertebrates near the stream mouth.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 5-7. A field work sheet or checklist, which can be used inthe field, is provided in Table 5-8.Future resource monitoring can be effectively performed through bi-annual site visits to theVatia wetland. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Vatia Village Council. Assuming thatresidents cooperatively permit periodic access for long-term resource monitoring, fieldmonitoring should begin at the stream mouth and extend 500 upstream. The only specificmonitoring station within this area would be established approximately 10 feet upstream of thestream mouth where fish and invertebrate collections will take place.Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS. PPC has provided digital files for the Wetland and Stream Restorationand Enhancement Plan that provide a departure point for locating future resource monitoringstations along Faatafe Stream.All photographs should be incorporated into the digital photo album developed by PPC inconjunction with the Wetland/Stream Restoration and Enhancement Plan. This will enable along-term comparison of resource information.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-14

TABLE 5-7LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVATIA WETLANDResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream flow 1 x (Dec-March) Visual observation Faatafe Stream mouth to 500 feet upstream Presence of stream flow or obstructions to stream flowHydrology 1 x (April-Nov) Visual observationWetland outlet 1 x (Dec-March) Visual observation Faatafe Stream mouth Presence of stream flow or obstructions to stream flow1 x (April-Nov) Visual observationStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually 500 feet upstream of Faatafe Stream mouth Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new mangrove Betweem stream mouth and 500 feet upstream Number of plants that remainvegetation 1 x (April-Nov) propagules, riparian and fruit trees, andcoastal plantsWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of Faatafe Stream channel Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, discharges into wetland or stream channel?incorporate data into GISAquatic Fish Type and number 2 x (Dec-March) Collection of driftnet samples of outgoing10 feet upstream of Faatafe Sream mouth Changes in diversity and abundance of fish & crustaceans.and Invertebrates of fish and 2 x (April-Nov) larvae for 3-4 hour evening periodscrustaceans(See report narrative.)Molluscs Type and number 2 x (Dec-March) Mark - recapture technology or 10 feet upstream of Faatafe Stream mouth Changes in diversity and abundance of molluscs.of molluscs 2 x (April-Nov) quadrant counts at night

TABLE 5-8FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVATIA WETLANDDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):PAGE 1 OF 2 PAGESFaatafe StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream? Yes No2a Are stream flows entering Leone Pala? Yes Nob If no, what appears to be impeding stream discharge? Describe.STREAM CHANNEL MODIFICATIONS3 a Has the stream bank been altered and with what material has the alteration been made? Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map _____ Check, when field map is so marked.4 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked5 a Is there evidence of bank erosion? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Do you see evidence of a change in the stream flow path? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedSURVIVAL OF NEW RIPARIAN PLANTS7 Count number of surviving new riparian treesCHANGES IN LAND USE8 a Document type and number of new land uses within 100 feet of stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked9 a Do any existing land uses, within 100 feet of the stream channel, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL OR WETLAND10 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial11 Locate discharge on field map. ___ Check, when field map is so marked

TABLE 5-8 (CONTINUED)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVATIA WETLANDPAGE 2 OF 2 PAGESFISH AND INVERTEBRATES12 Identify the type and number of fish observed via the collection of driftnet samples of outgoing larvae.Family Genus/Specie Number Observeda Fishb CrustaceansMOLLUSCS13 Identify the type and number of molluscs that were observed by mark-recapture technology or quadrant counts.Family Genus/Specie Number Observed

More specific monitoring of stream fauna should be made immediately upstream of the FaatafeStream crossing of the shoreline vehicular trail to Vatia Village. Such monitoring shouldinclude the collection of driftnet samples of outgoing larvae, at least two times per month, for3-4 hour periods in the evening. The driftnets (150-200 ųm mesh) should be attached to rebarpounded into the stream substrata, or simply suspended from trees or bridges to that the net isat the surface of the water. The samples would subsequently be preserved in ethanol. The typeand number of fish and crustaceans should be enumerated using a dissecting microscope. Useof a dissecting microscope will likely require a 2-3 day training class and the necessaryequipment.Molluscs should be monitored by mark-recapture methodology, or quadrant counts at nightsince most are primarily nocturnal. Some training in these techniques is recommended forselected field monitoring personnel.Site MaintenanceA one-time cleanup effort will represent an important first step toward long-term streamenhancement. However, the initial cleanup is of limited benefit if it is not associated with theimplementation of a long-term maintenance strategy.Periodic site maintenance should take place within the project area approximately four timesper year. Household wastes along the lower reaches of Faatafe Stream are expected torepresent the primary focus of long-term site maintenance. The periodic long-term maintenanceof the Faatafe Stream culvert underneath the primary shoreline trail will be necessary to ensureadequate tidal exchange and the maintenance of brackish water quality.A crew of three to four persons will be necessary to periodically walk the 450-foot length oflower Faatafe Stream, as well as related road culvert immediately upstream of the streammouths. Such inspections would occur shortly after significant rainfall and stormwater events.Machetes and weed-eaters will be required to periodically trim vegetation along selectedportions of the stream channel. The manual collection of solid wastes will also be necessary tominimize obstructions to stream discharge and effective tidal exchange.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vatia Wetland, Page 5-18

Chapter SixVAIPITO STREAMLOCATIONThe Vaipito Stream drainage is situated upland of the inner Pago Pago Harbor and Pago PagoVillage (Figure 6-1). The stream segment investigated included the lower end of VaipitoStream that extends from the Vaipito Stream mouth to about 2,725 feet upstream of theshoreline (Figure 6-2).STREAM HYDROLOGYSources of Surface RunoffThe Vaipito Stream drainage encompasses approximately 1.36 square miles of land area (U.S.Army Corps of Engineers, Honolulu District, 1990). This drainage receives surface runofffrom Gagamoe Stream, Laolao Stream, Pago Stream, Leau Stream, Vaima Stream, UtumoaStream, and Aga Stream (Figure 6-2).The Vaipito Stream drainage originates near the 1,200-foot elevation on the northwest slopes ofMt. Matafao. The main stem of Vaipito Stream flows through Pago Pago Village just east ofRoute 5. The stream channel passes along the northwest side of Pago Plaza and bisects PagoPark before discharging into the nearshore waters of inner Pago Pago Harbor.The lower stream channel that bisects Pago Park also receives surface runoff from a secondunnamed ditch and channel that is located on the south and east sides of Pago Pago ElementarySchool. This channel passes along the north side of a Mormon Church complex (on thesouthwest side of Route 1) and continues for about 800 feet before its confluence with the mainstem of Vaipito Stream.General Stream CharacteristicsThe lower Vaipito Stream channel segment represents a relatively narrow and deep channel.Exposed basalt boulders and man-made walls form the margin of the stream channel. Thestreambed typically contains a combination of medium to large basalt boulders, smaller rockcobble, sand, and decomposed organic material. Limited areas of the channel bottom are linedwith concrete.A considerable amount of household garbage and discarded organic material was found atvarious points within the streambed. With increased building densities in Pago Pago, a numberof landowners have also encroached their site development upon stream banks to help increasethe size of concrete driveways and vehicular parking areas.Rock walls and rock-filled gabions are located along various points of the lower streamchannel. They have apparently been installed to help prevent flood damages associated withhigher stormwater events, as well as protect properties from erosion along the stream bank.However, stream bank hardening and alterations of stream flow path have significantlyimpacted stream hydrology. Increased stream velocities, combined with alterations in streamflow path, have contributed to the failing of some gabions along Vaipito Stream.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-1

Figure 6-1Location MapVaipito Stream DrainageAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-2

Figure 6-2Vaipito Stream SegmentExisting ConditionsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-3

Stream FlowsHistorical Stream FlowsIntermittent stream flow records have historically been collected by the U.S. Geological Surveyalong two tributaries of Vaipito Stream (Table 6-1). The data gained from these stream gagesprovide an insight of runoff volumes that historically have emptied into lower Vaipito Stream.TABLE 6-1MEDIAN STREAM FLOW ESTIMATESTRIBUTARIES OF VAIPITO STREAMStream USGSGageStationGage LocationVaima Stream 16949700 0.4 mile upstream fromVaipito Stream.Utumoa Stream 16949800 0.6 mile upstream ofVaipito Stream andimmediately upstream ofVaipito intake.Utumoa Stream 16950500 0.2 mile downstream ofUtumoa Stream pipeline.Source: Wong, 1996Stream FlowMeasurements(number)EstimatedMedian Flow (cfs)20 0.1629 0.4217 0.25Stormwater Discharges, Flood Potential, and ErosionPedersen Planning Consultants made a hydrologic analysis of potential stormwater dischargesinto inner Pago Pago Harbor via a range of potential storm events. Through hydrologicmodeling, PPC determined that potential stormwater discharges into inner Pago Pago Harborcould range from 862 cubic feet per second (cfs) for a 2-year storm and about 3,683 cfs for a100-year storm (Table 6-2). Consequently, significant stream flows can be carried by VaipitoStream for more common 2-year events, as well as less frequent 100-year storms.TABLE 6-2STORMWATER RUNOFF DISCHARGES INTO INNER PAGO PAGO HARBORFROM VAIPITO STREAM DRAINAGE2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 2-Year Storm 10-Year Storm 50-Year Storm 100-YearStormVaipito Stream 612 1,084 2,137 2,608Unnamed Stream 220 391 775 947Gagamoe Stream 30 53 104 128TOTAL 862 1,528 3,016 3,683Source: Pedersen Planning Consultants, 2000Ten, 50, and 100-year flood plains determined by the U.S. Army Corps of Engineers, HonoluluDistrict, in 1988 suggest that greater flood potential is generally downstream of the VaipitoAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-4

Stream/Pago Stream confluence. In a related reconnaissance report, the U.S. Army Corps ofEngineers concluded:“The greatest flood problem occurs in the downstream area, approximately 600 feet above themain highway (Route 1) down to the mouth. While the outlet has ample flood carryingcapacity, the existing bankfull capacity of Vaipito Stream in the land-filled area (Pago Park) is1,100 cfs, a discharge slightly greater than a 2-year flood” (U.S. Army Corps of Engineers,1988).While flooding typically occurs on the lands within Pago Park, flooding in this area typicallygenerates limited to no property damage since few structures are located within the Park. Inrecent years, however, more governmental buildings have been constructed along Route 1 andthe west margin of the Park. The blockage of culverts along Route 1 frequently generatesflooding within and around these buildings following more frequent storm events.Erosion poses a problem upstream of Route 1, particularly along bends of the stream. “Streambanks exposed to the erosive forces of the stream are provided minimal protection with a thinconcrete blanket” (U.S. Army Corps of Engineers, 1988).Stream CapacitiesThe U.S. Army Corps of Engineersalso modeled stream capacities aspart of its 1988 reconnaissancereport for Vaipito Stream (Table 6-3).VEGETATIONNovember 1999 SurveyTABLE 6-3ESTIMATED VAIPITO STREAM CAPACITIESStation LocationCapacity (cfs)0+00 to 7+00 1,6007+00 to 18+00 1,10018+00 to 28+00 1,20028+00 to 38+00 70038+00 to 54+00 870Source: U.S. Army Corps of Engineers, 1988Art Whistler of Isle Botanica conducted a botanical survey of the Vaipito Stream segment onNovember 4, 1999. Mr. Whistler was part of a three-person field survey team organized byPedersen Planning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.Vaipito Stream Mouth and Confluence with Unnamed StreamThe stream banks, between the Vaipito Stream mouth and its confluence with the unnameddrainage from Pago Pago Elementary School, were dominated by a mixture of alien plantspecies. Some of these species were typical of a wetland; others were indicative of an uplandenvironment. Most of the relatively flat stream bank areas were characterized by salt grass(Paspalum vaginatum), Fimbristylis cymosa, and carpet grass (Axonopus compressus), as wellas scattered concentrations of fue moa (beach morning-glory).Roughly 30 other alien herbaceous plants were noted along the stream banks just upstream ofthe Vaipito Stream mouth. Along the south bank of the stream, there were thickets of wildtamarind (Leucaena leucocephala), scattered fau (beach hibiscus) trees, patches of elephantgrass (Pennisetum purpureum), beggar’s tick (Bidens alba), beach morning-glory, andAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-5

California grass (Brachiaria mutica). Only fau (beach hibiscus) and Fimbristylis cymosa arenative plants.Between Unnamed Stream/Vaipito Stream Confluence and Route 1Between the unnamed stream/Vaipito Stream confluence and Route 1, the Vaipito Streamchannel became narrower. The stream bank typically was lined with a basaltic rock or concretewall. California grass was dominant immediately upland of the stream channel margin. Lesseramounts of Sorghum sudanense, fue saina (mile-a-minute vine), beggar’s tick, taamu (gianttaro), sanasana (Job’s tears), and bananas were also evident along this stream segment.Upstream of Route 1Upstream of Route 1, the Vaipito Stream becameincreasingly channelized. Stream banks representeda combination of basaltic rock walls, concrete walls,rock-filled gabion baskets, and exposed dirtembankments. These characteristics left a narrowzone for the growth of vegetation.Job’s tears, California grass, taamu (giant taro) andmile-a-minute vine were prevalent along streamsegments that were characterized by dirtembankments. Various trees were also scatteredalong the stream banks. These trees primarilyincluded ulu (breadfruit), vavae (kapok), beachhibiscus, falaga (Barringtonia samoensis), pulu(banyan), lau pata (Macaranga harveyana), mango,coconut, and banana.Vegetation TrendsLower Vaipito Stream was once characterized by a healthy mangrove swamp. However, theswamp was filled by the U.S Navy in the early 1960’s to support past naval activities.Subsequently, the use of the landfill area was converted to its present day recreational use withthe establishment of Pago Park.In 1996, significant restoration efforts were made by the American Samoa EnvironmentalProtection Agency and the American Samoa Community College, Land Grant Program alongselected portions of lower Vaipito Stream.Following initial coordination with the pulenuu and village council of Pago Pago Village,ASEPA and ASCC Land Grant program personnel planted 127 trees just upstream of theVaipito Stream mouth on September 28, 1996. These trees were planted along the east side ofthe stream.In mid-October and early November of 1996, an additional 1,000 feet of stream bank wasplanted upstream of Vaipito Stream’s unnamed lower confluence. Most of 238 trees plantedwere seedlings that were propagated at ASCC Land Grant facilities during the summer of 1995.One exception was fau trees that represented 2.5-foot long cuttings. All of the trees wereplanted and spaced at six-foot intervals. Falaga (Barringtonia samoensis) was planted alongAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-6

the lower bank above mean sea level. Mangroves were planted downstream of the foot bridgethat connects Pago Park and the vehicular parking area at Pago Plaza (Steele, 1996).Between Route 1 and the Vaipito Stream/Pago Stream confluence, an additional 205 trees wereplanted in late December, 1996. This restoration effort primarily included the planting of ifiand falaga. With the presence of more riparian vegetation along this stream segment, fewertrees were required for stream bank restoration (Steele, 1996).Despite these aggressive efforts, lower Vaipito Stream remains a highly degraded plant habitat.There is no utuutu or vao tuaniu, or native marsh vegetation along the stream banks. Therealso is very little falaga or ifi along the stream banks. Their absence, combined with thepresence of banana, mango, and kapok are indicative of disturbance.AQUATIC FISH AND INVERTEBRATESGeneralOn November 4, 1999, Charles Chong of the PPC field survey team made observations ofaquatic fish and invertebrates along selected portion of lower Vaipito Stream. An upland sitelocation was also investigated along Utumoa Stream, a significant upland tributary of VaipitoStream (Figure 6-3). His observations are summarized in the following paragraphs.Stream flows observed during the survey weregenerally fast-moving along the length of lowerVaipito Stream. A flow of about 2 to 3 cfs wasobserved at the Vaipito Stream mouth. Thestream mouth terminated with a fast riffleentering inner Pago Pago Harbor.A considerable amount of household garbageand other solid waste material was observedthrough much of the stream course.FishAn individual unidentified goby was observedalong Utumoa Stream. Three unidentifiedindividual gobies were documented in a poolbelow a small gage dam. With the exception ofthese fish, the only other fish observed along thestream were Poecilia.Kuhlia and Mugil spp. were abundant near theVaipito Stream mouth. However, Kuhlia spp. wasabsent upstream of the stream mouth.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-7

FIGURE 6-3FISH AND INVERTEBRATE SURVEY LOCATIONSAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-8

InvertebratesThe lower Vaipito Stream segment possessed higher densities of crustaceans at lowerelevations, as well as upstream along Utumoa Stream, a major upland tributary. Healthycrustacean fauna appeared to be pristine upstream of the residential area along Vaipito Stream.In contrast, lower specie diversity was evident adjacent to residential areas.Marcrobrachium lar, as well as Caridina and Macrobrachium lutimanus, was abundantupstream along Utumoa Stream. Two species of neritid molluscs were present along UtumoaStream, but were not abundant.Along lower Vaipito Stream, Macrobrachium lar remained abundant downstream.Macrobrachium australe was common. One specie of molluscs was also observed along thelower elevations of the stream.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey is summarizedin Table 6-4. Genera are listed in order of descending abundance within their taxonomic group.TABLE 6-4SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED ALONG VAIPITO STREAM DRAINAGEStream Location Fishes Crustaceans MolluscsVaipito Stream mouth to KuhliaMacrobrachium NeritinaRoute 1 crossingMugilPoecilia(2 spp.)UnidentifiedGraspid crabUtumoa Stream Unidentified goby CaradinaMacrobrachium(2 spp)Neritina (2 spp.)Source: Chong, 2000The relative abundance and diversity of fish and invertebrates along the Vaipito Streamdrainage is summarized in Table 6-5. The characterization of relative abundance and diversityreflects a general comparison of the abundance and diversity of fish and invertebrates observedalong portions of the Vaipito Stream drainage with all 10 sites evaluated for theWetland/Stream Restoration and Enhancement Plan.Vaipito Stream contained a high diversity and abundance of invertebrates. However, fishdiversity and abundance were low.TABLE 6-5RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESVAIPITO STREAMFishes Crustaceans MolluscsAbundance Low High LowDiversity Low High MediumSource: Pedersen Planning Consultants, 2000LAND USES ADJACENT TO VAIPITO STREAMAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-9

Most of lower Vaipito Stream segment is situated immediately adjacent to residential uses.Seaward of the Route 1 bridge, Pago Plaza and some public facilities area are locatedimmediately adjacent to the stream channel.Immediately upstream of the stream mouth, PagoPark is situated along the north and south sides ofVaipito Stream.Solid waste discarded from the residents alongVaipito Stream poses the greatest impact uponstream hydrology and aquatic habitat. However,discarded solid waste material did not appear tosignificantly constrain the flow of surface runoffalong the main stem of the stream.RIPARIAN RESTORATION AND ENHANCEMENT STRATEGIESGeneralOnly one practical opportunity was identified for the restoration of lower Vaipito Stream. Thescope of this restoration opportunity and related implementation strategies are presented in thefollowing paragraphs. The potential benefits and impacts derived from the implementation ofthe recommended strategies are subsequently evaluated and compared with a “no action”option.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Opportunities and StrategiesOption 1: Restore Mangrove Forest along Lower Vaipito StreamThe initial phase of this restoration effort will involve a general cleanup of lower VaipitoStream (Figure 6-4). The cleanup should be made between the Vaipito Stream mouth and theRoute 1 crossing over Vaipito Stream. This effort will require the collection and disposal of awide variety of solid waste materials for approximately 1,360 feet upstream of the streammouth. Manual collection will be sufficient to collect most of this material. However, a largerdump truck may be required to haul larger materials to the Futiga landfill. Availableequipment from either the American Samoa Power Authority or the American SamoaDepartment of Public Works should be requested and used to support the cleanup effort.Following the initial stream cleanup, roughly 220 plantings of red mangrove (Rhizophoramangle) and 220 oriental mangrove (Bruguiera gymnorrhiza) should be made between thestream mouth and the foot bridge that connects the north and south sides of Pago Park. Thissegment of the stream extends roughly 650 feet upstream of the stream mouth.FIGURE 6-4American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-10

OPTION 1: RESTORE MANGROVE FOREST ALONG LOWER VAIPITO STREAMAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-11

Red mangrove should be planted within the stream bed since red mangrove can sustain itself inwaters with somewhat higher salt water concentrations (Stemmermann, 1981). In contrast,oriental mangroves should be planted higher along stream banks (Steele, 1999).The initial planting of mangroves propagules or seedlings should be approximately 3 feet apart.Within three years, mangroves should be thinned to about a six-foot spacing between eachplant (Steele, 1999).The diversity of riparian vegetation could also be enhanced with the addition of 100 ifi(Tahitian chestnut) and falaga along the stream banks. However, these trees should be plantedat least 200 feet upstream of the Vaipito Stream mouth to keep the trees away from streamareas subjected to tidal influence.Trees along the stream banks would also be interspersed with the planting of approximately100 littoral/coastal plants. Such plantings would include a combination of fetau, pu’a, gataeand talie.In-stream plantings of red mangrove should be carried out by experienced technicians of theASCC Land Grant Program. However, Land Grant representatives should attempt to involvelocal residents in the replanting of oriental mangrove, as well as ifi and falaga trees along thestream banks.Option 2: No ActionASEPA and the American Samoa Community College, Land Grant Program completed asignificant stream restoration project in 1996 that resulted in the planting of some 569 treesalong lower Vaipito Stream. In view of these improvements, Option 2 would make no furtherstream restoration and enhancement improvements along Vaipito Stream.Comparative Benefits and ImpactsPPC’s evaluation of the two alternate restoration and enhancement strategies is summarized inTable 6-6. Option 1 would restore mangrove vegetation just upstream of the Vaipito Streammouth and provide significant improvements to wetland and riparian vegetation, as well asstream bank stability, for a reasonable cost. These improvements would also enhance theattractiveness of adjoining Pago Park and not constrain recreational uses in this area. Thepresence of government lands in the restoration area will also facilitate access to futureplantings and thinning activities, as well as long-term monitoring. In addition, some nominalimprovements in fish and invertebrate habitat may be generated from in-stream plantings of thered mangrove.The viability of mangrove restoration upstream of the Vaipito Stream mouth has some risks.Larger stormwater events may remove all plantings until the mangrove trees become wellestablished. In addition, mangrove plantings will also somewhat diminish the capacity of thestream to discharge higher stream flows following stormwater events.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-12

TABLE 6-6COMPARATIVE EVALUATIONRIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESLOWER VAIPITO STREAMOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetland/RiparianVegetationStreamBankStabilityFlood Hazards& PropertyDamage1 LC NBC NBC LB SB SB NBC2 NBC NBC NBC NBC LC NBC NBCNotes:Potential project benefits were rated by PPC as follows:SB Significant project benefitsLCMB Moderate project benefitsMCLB Limited project benefitsSCNBC No anticipated project benefits orundesirable consequencesLimited undesirable consequencesModerate undesirable consequencesSignificant undesirable project impactsSource: Pedersen Planning Consultants, 2000Recommended Option and Estimated Project CostThe restoration of the mangrove forest immediately upstream of the Vaipito Stream mouth(Option 1) is recommended for implementation. This wetland restoration project isrecommended because the project can provide significant improvements to wetland vegetation,enhance the adjoining recreational area, and possibly provide increased habitat for fish andinvertebrates.The costs associated with the restoration of the mangrove forest would primary be associatedwith the initial clearing of solid waste material from the lower reach of Vaipito Stream. Morespecifically, the cleanup would be made between the stream mouth and the Route 1 crossing ofVaipito Stream. The subsequent collection and planting of mangrove, ifi, and falaga treecuttings would be carried out by the ASCC Land Grant Program.These estimated cost associated with the initial clearing of the Vaipito Stream mouth and theupstream area would be $2,036 (Table 6-7). The planting of mangrove and native riparian treeswould cost an estimated $5,251 (Table 6-8). Consequently, the total project cost anticipatedfor the overall project is roughly $7,287.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-13

TABLE 6-7PRELIMINARY COST ESTIMATECLEARING OF LOWER VAIPITO STREAM MOUTH AND UPSTREAM AREALABORPersonnel Number Hours Hourly Rate ($) Cost ($)Supervisor 1 16 15 240Heavy Equip. Operator 1 16 13 208Laborer 2 16 6 192All Personnel 4 64 $640MATERIALSItem Quantity Unit Cost ($) Cost ($)Picks 3 15 45Sledge Hammers 3 25 75Shovel 3 22 66Weed-eaters 3 300 900Machetes 3 20 60Garbage Bags 20 boxes 5 100Wheel Barrows 3 50 150All Materials $1,396TOTAL LABOR AND MATERIALS $2,036Notes: Preliminary estimate assumes use of existing equipment that is owned by the ASG Department of PublicWorksSource: Pedersen Planning Consultants, 2000TABLE 6-8PRELIMINARY COST ESTIMATEPLANTING OF TREES UPSTREAM OF VAIPITO STREAM MOUTHLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 12 8 96ASCC Field Crew Members 2 12 6 144All Personnel 4 140 $1,280MATERIALSItem Quantity Unit Cost ($) Cost ($)Native Riparian Trees 100 3 300Mangrove Trees 440 5 2,200Littoral/Coastal Plants 100 5 500Garbage Bags 20 boxes 5 100All Materials $3,100EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $5,251Source: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-14

Long-term resource management activities associated with the restoration of the lower reach ofVaipito Stream should include the seasonal monitoring of selected resource characteristics andperiodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.Long term monitoring of the Vaipito Stream restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of stream flow;• potential impedances to stream discharge;• evidence of eroding stream bank areas;• potential failures or damages to gabion baskets or rock walls along the stream bank;• survival of planted, riparian and littoral/coastal vegetation;• potential flood damages to commercial and public facility properties;• changes in land uses immediately adjacent to the stream banks;• point-source discharges, e.g., storm water; and,• changes in the type and number of fish and invertebrates near the stream mouth.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 6-9. A field work sheet or checklist, which can be used inthe field, is provided in Table 6-10.Future resource monitoring can be effectively performed through bi-annual site visits to lowerVaipito Stream. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-15

TABLE 6-9LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVAIPITO STREAMResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Vaipito Stream mouth to 650 feet upstream Presence of stream flow or obstructions to stream flowHydrology1 x (April-Nov)Wetland Outlet 1 x (Dec-March) Visual observation Vaipito Stream mouth Presence of stream flow or obstructions to stream flow1 x (April-Nov)Stream Channel Stream channel 1 x (Dec-March) Measure manually, using tape measure Vaipito Stream: 600 feet upstream of wetland Changes in dimensions of stream channel trapezoidcross sections 1 x (April-Nov) at 100-foot intervalsStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually Vaipito Stream: 650 feet upstream of wetland Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of Vaipito Stream segment Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, discharges into the stream channels?incorporate data into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new mangrove Between Vaipito Stream mouth and 650 feet Number of plants that remainvegetation 1 x (April-Nov) propagules, riparian trees, and coastal/ upstreamlittoral plants.Aquatic Fish Type and number 2 x (Dec-March) Collection of driftnet samples of outgoing10 feet upstream of Vaipito Stream mouth. Changes in diversity and abundance of fish andand Invertebrates of fish and 2 x (April-Nov) larvae for 3-4 hour evening periods. crustaceans.crustaceans(See report narrative for detail.)Molluscs Type and number 2 x (Dec-March) Mark-recapture technology or quadrant 10 feet upstream of Vaipito Stream mouth. Changes in diversity and abundance of molluscs.of molluscs 2 x (April-Nov) counts at night.

TABLE 6-10FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVAIPITO STREAMDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):PAGE 1 of 3 PAGESVaipito StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no")1 Is water flowing in the stream (between Vaipito Stream mouth and Route 1)? Yes No2a Are stream flows discharging into Pago Pago Harbor? Yes Nob If no, what appears to be impeding stream discharge? Describe.STREAM CHANNEL MODIFICATIONS3 a Has the stream bank been altered and with what material has the alteration been made? Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map. _____ Check, when field map is so marked.4 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked5 a Is there evidence of bank erosion? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Do you see evidence of a change in the stream flow path? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID7 Refer to page 3: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW WETLAND PLANTS8 a Count number of surviving new mangrove treesb Count number of surviving new fruit treesc Count number of new coastal plantsd Count number of surviving littoral plantsCHANGES IN LAND USE9 a Document type and number of new land uses within 100 feet of Vaipito Stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked10 a Do any existing land uses, within 100 feet of the stream channel, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL11 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial12 Locate discharge on field map ___ Check, when field map is so marked

TABLE 6-10 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVAIPITO STREAMPAGE 2 of 3 PAGESFISH AND INVERTEBRATES13 Identify the type and number of fish observed via the collection of driftnet samples of outgoing larvae collected near Vaipito Stream mouth.Family Genus/Specie Number Observeda FishbCrustaceansMOLLUSCS14 Identify the type and number of molluscs that were observed by mark-recapture technology or quadrant count near Vaipito Stream mouth.Family Genus/Specie Number Observed

TABLE 6-10 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVAIPITO STREAMCHANGES IN STREAM CHANNEL TRAPEZOID7 For each trapezoid represented below, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.PAGE 3 of 3 PAGESStationVaipito Stream1+ 00 EABCFD2 + 00 EABCFD3 + 00 EABCFD4 + 00 EABCFD5 + 00 EABCFD6 + 00 EABCFD

Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Pago Pago Village Council. Assumingthat residents cooperatively permit periodic access for long-term resource monitoring, fieldmonitoring should begin at the stream mouth and extend 650 upstream. The establishment ofmonitoring stations should begin at the stream mouth and continue upstream at 100-footintervals.Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS. PPC has provided digital files for the Wetland and Stream Restorationand Enhancement Plan that provide a departure point for locating future resource monitoringstations along lower Vaipito Stream.All photographs should be incorporated into the digital photo album developed by PPC inconjunction with the Wetland/Stream Restoration and Enhancement Plan. This will enable along-term comparison of resource information.More specific monitoring of stream fauna should be made immediately upstream of the VaipitoStream mouth. Such monitoring should include the collection of driftnet samples of outgoinglarvae, at least two times per month, for 3-4 hour periods in the evening. The driftnets (150-200 ųm mesh) should be attached to rebar pounded into the stream substrata, or simplysuspended from trees or bridges to that the net is at the surface of the water. The sampleswould subsequently be preserved in ethanol. The type and number of fish and crustaceansshould be enumerated using a dissecting microscope. Use of a dissecting microscope willlikely require a 2-3 day training class and the necessary equipment.Molluscs should be monitored by mark-recapture methodology, or quadrant counts at nightsince most are primarily nocturnal. Some training in these techniques is recommended.All photographs should be incorporated into the digital photo album developed by PPC inconjunction with the Wetland/Stream Restoration and Enhancement Plan. This will enable along-term comparison of resource information.Site MaintenanceA one-time cleanup effort will represent an important first step toward long-term streamenhancement. However, the initial cleanup is of limited benefit if it is not associated with theimplementation of a long-term maintenance strategy.Periodic site maintenance should take place within the project area approximately four timesper year. Household and commercial wastes along the lower 1,360 feet of Vaipito Stream areexpected to represent the primary focus of long-term site maintenance. Various wastes fromPago Pago Harbor will be more evident at the Vaipito Stream mouth. Maintenance of theVaipito Stream mouth is especially important to ensure adequate tidal exchange and themaintenance of brackish water quality.A crew of three to four persons will be necessary to periodically walk the 1,360-foot length oflower Vaipito Stream. Such inspections would occur shortly after significant rainfall andstormwater events. Machetes and weed-eaters will be required to periodically trim vegetationalong selected portions of the stream channel. The manual collection of solid wastes will alsobe necessary to minimize obstructions to stream discharge and effective tidal exchange.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Vaipito Stream, Page 6-20

LOCATIONChapter SevenPAPA STREAMPapa Stream is generally situated north of Pala Lagoon along the southern coast of the Island ofTutuila (Figure 7-1). The stream segment examined in this study extends about 1,200 feetupstream of Route 1 (Figure 7-2).STREAM HYDROLOGYSources of Surface RunoffThe Leele-Papa-Tauese Stream drainage carries surface runoff from the east and southeastslopes of Leele Mountain to Pala Lagoon. The apex of this drainage begins near at the summitof Leele Mountain near the 1,724-foot contour.Available 1:200 scale topographic maps for the Island of Tutuila indicate that Leele Streamoriginates near the 825-foot contour. The confluence of the main stem of Leele Stream and onesmaller upland tributary occurs at about the 325-foot elevation. Downstream of thisconfluence, Leele Stream becomes Papa Stream. Consequently, Papa Stream represents thedownstream portion of the Leele-Papa Stream drainage (Figure 7-1).The 1,200-foot segment of Papa Stream, which is the subject of the Wetland/StreamRestoration and Enhancement Plan, flows through the northern portion of the inhabited NuuuliVillage area (Figure 7-2). The surface runoff from Leele Stream and its upland tributary is theprimary contributor of surface runoff to this segment of Papa Stream.In November 1999, PPC observed that a culvert was installed along the east bank of PapaStream that enables the transport of runoff from a local road improvement west of Papa Stream,as well as stream discharges of Tauese Stream, to discharge into Papa Stream. The hydrologicconnection of Tauese Stream and Papa Stream is not clearly evident on available 1:200 scaletopographic maps. U.S. Geological Survey references to the location of one low-flow, partialrecord station (No. 16944000) confirm that this hydrologic connection between Tauese Streamand Papa Stream has existed for some time (Wong, 1996).General Stream CharacteristicsThe 1,200-foot segment of Papa Stream extends from a concrete weir at station 11+80 to adouble culvert below Route 1 (Figure 7-2). The concrete weir was associated with a formerdam that was constructed to establish a small surface water reservoir.Cross-sections documented by PPC in November 1999 indicate that the width of the streamsegment (between east and west stream banks) ranges between 15 and 33 feet. The depth ofthe stream channel (between the top of bank to the bottom of the stream bed) is between twoand 12 feet along the east side of the stream. Along the west side of the stream, the depth ofthe stream channel ranges between 2 and 8 feet below the stream bank.The stream channel bed is composed of exposed basalt and larger boulders, smaller rockcobble, sand, and decomposed organic material. Rock and solid waste material are foundwithin and the along the banks of various portions of the stream.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-1

Figure 7-1Location MapLeele-Papa-Tauese Stream DrainageAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-2

Figure 7-2Papa Stream SegmentExisting ConditionsAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-3

Stream flow, in some cases, is constrained by larger rock and solid waste material that havegradually re-directed the direction of stream flows along some areas within the stream course.These modifications in stream hydrology have, in turn, generated the erosion of stream banksin various locations.Stream ModificationsModifications in stream hydrology along Papa Stream are primarily due to past man-madeefforts to reduce bank erosion and protect properties adjacent to the stream banks. A fewexamples are identified in the following paragraphs.In the vicinity of station 4+00, an 8-foot high rock wall is located about 10 feet west of the weststream bank. This wall was apparently constructed to reduce potential property damages thatcan be generated from occasional stormwater events. In November 1999, this wall appeared tobe in good structural condition and not impacted by past stormwater events.In November 1999, failing gabion baskets were discovered just downstream of station 11+80along the west bank of the stream. However, upon return to this area in late June 2000, PPCand ASEPA representatives observed newly constructed stream modifications along the westbank of the stream.A new 50-foot section of concrete wall, aneight-foot wide section of rock-filled gabions,two terraced gabions, and an 80-foot length ofconcrete wall were constructed immediatelydownstream of the concrete weir at station11+80. This stream modification clearlynarrowed the former stream width by about 10-20 feet. In addition, the installation of concretewall sections will likely increase the velocity offuture stream flows along this reach of PapaStream. Such modifications can also beexpected to generate downstream consequencessuch as bank erosion and damage to rock-filledgabion baskets.Immediately upstream of station 11+80, an 8-10 foot length of rock-filled gabions wasobserved along the east bank of Papa Stream. A local resident informed PPC representativesthat this section of rock-filled gabions had remained along the east bank of the stream for about12 years and effectively protected adjacent residential property from occasional flooding andpotential property damage.During the June 2000 site visit, ASEPA and PPC representatives also investigated a significantstream modification about 700-800 feet upstream of the concrete weir (station 11+80). Theconstruction of a basaltic rock wall along the west bank of Papa Stream in 1998 relocated themain stem of the stream channel east of its former stream path (Galeai, 2000). However, aportion of the former channel remained as a long narrow island was observed approximately100-150 feet downstream of the basaltic rock wall.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-4

Immediately downstream of these two parallel stream channels, a single main stem wasestablished. However, the stream alteration in this area significantly eroded lands along the eastbank of the stream. Informal discussions with the adjoining landowner, George Galeai, as wellas uprooted ifi, coconut, and other trees provided ample evidence of the consequencesassociated with the upstream modification.Stream FlowsHistorical Stream FlowsIn 1996, the U.S. Geological Survey (USGS) published an estimated median stream flow forPapa Stream (Table 7-1). The median stream flow estimate was based upon historical streamflow measurements obtained from a continuous-record gage (No. 16944200) that was situated500 feet downstream of Papa/Tauese Stream confluence between 1966 and 1976. The samegage was occasionally operated as a partial-record site between 1968 and 1983. The highestflow recorded at this stream gage was 1,640 cubic feet per second (cfs) on April 29, 1975.However, USGS reported that stream flows were absent from this stream location for manydays of the year.A low-flow, partial record station (No. 16944000), which was located 0.3 mile upstream of thePapa/Tauese Stream confluence, provided 30 stream measurements between 1959 and 1990.The U.S. Geological Survey estimated a median stream flow of 1.48 cfs at this station location(Wong, 1996).TABLE 7-1MEDIAN STREAM FLOW ESTIMATEPAPA STREAMStream USGSGageStationGage LocationPapa Stream 169442000 500 feet downstream fromPapa/Tauese StreamconfluencePapa Stream 16944000 0.3 mile upstream of Papa/Tauese Stream confluenceSource: Wong, 1996Stream FlowMeasurements(number)Continuousintermittentlybetween 1966-1976Estimated MedianFlow (cfs)1.3030 1.48American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-5

Stormwater Discharges and Related Flood PotentialIn 1999, Pedersen Planning Consultants recently made a hydrologic analysis of potentialstormwater discharges into Pala Lagoon that could be generated from a range of storm events(Pedersen Planning Consultants, 2000). Through hydrologic modeling, PPC determined thatpotential stormwater discharges into the Pala Lagoon can range from 739 cubic feet per second(cfs) for a 2-year storm and about 2,072 cfs for a 100-year storm. Consequently, significantstream flows can be carried by Papa Stream for more common 2-year events, as well as lessfrequent 100-year storms.TABLE 7-2STORMWATER DISCHARGES FROM PAPA STREAM INTO PALA LAGOON2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 2-Year Storm 10-Year Storm 50-Year Storm 100-Year StormPapa Stream 739 1,134 1,847 2,072Source: Pedersen Planning Consultants, 2000In November 1999, PPC also gathered cross-sectional data along the 1,200-foot Papa Streamsegment to assess the capability of this stream segment to accommodate these stormwaterevents. Cross sections were recorded at 100-foot intervals along this stream segment.With the application of hydrologic modeling, PPC determined that potential stormwater flowsare much larger than the capacity of the stream at each cross-section (Table 7-3). Oneimportant exception is the bridge culverts underneath Route 1 (station 1+00), which canaccommodate stormwater flows of about 2,162 cfs. Consequently, the culverts underneathRoute 1 can support potential flows from a 100-year storm event.TABLE 7-3CROSS-SECTIONAL ANALYSISALONG PAPA STREAM SEGEMENTMaximum Stream FlowStationSlope of Stream(percent)Through Cross Section(cfs)1+00 1.0 2,1622+00 1.0 3803+00 1.4 4204+00 1.5 6075+00 2.0 3446+00 1.2 1537+00 1.1 2228+00 1.2 3219+00 1.9 62910+00 1.6 51311+00 1.5 33211+80 1.3 292Source: Pedersen Planning Consultants, 2000American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-6

During its November 1999 survey, PPC representatives informally met with Mr. AiakopuSamuelo, a matai of Nuuuli Village and an ASG Department of Public Works road supervisor.Mr. Samuelo, who has lived in Nuuuli for 48 years, recalled his personal observations of floodwaters up to four feet above the top of the stream bank near station 4+00.The potential flood plain associated with a 100-year storm event in Nuuuli was mapped by theFederal Emergency Management Agency (FEMA) in May, 1991. Available flood insurancerate maps prepared by FEMA suggest that residential properties along the east and west banksof the Papa Stream segment could be flooded from a 100-year storm event.VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the Papa Stream segment onNovember 5, 1999 (Figure 7-2). Mr. Whistler was part of a three-person field survey teamorganized by Pedersen Planning Consultants that observed wetland vegetation, habitat foraquatic fish and invertebrates, stream hydrology, as well as land uses within and adjacent to thewetland. His observations are summarized in the following paragraphs.The vegetation of Papa Stream was comprisedof plants growing along the stream banks. Thedominant trees along the Papa Stream segmentincluded ifi (Tahitian chestnut), falaga(Barringtonia samoensis), afa (Neonaucleaforsteri), laupata (Macaranga harveyana), ulu(breadfruit), and mango. Underneath thesetrees, the ground cover was dominated bywetland plants such as California grass, Job’stears, and mile-a-minute vine. Lesser amountsof willow primrose, (Ludwigia octovalis) andCentosteca lappacea, Kyllinga nemoralis,beggar’s-tick (Bidens alba), and basket grasswere also observed.Vegetation along Papa StreamVegetation TrendsNo prior studies of the vegetation of Papa Stream have been conducted. Consequently, nocorrelation can be made concerning historical vegetative trends.The continued use of the adjoining lands for established residential use suggests that existingvegetation will generally remain the same. At the same time, the planting of more trees such asbanana and breadfruit is probable as residents supplement their diets with these traditionalcrops.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-7

AQUATIC FISH AND INVERTEBRATESGeneralOn November 5, 1999, Charles Chong of the PPC field survey team made observations ofaquatic fish and invertebrates along the 1,200-foot segment of Papa Stream. His observationsare summarized in the following paragraphs.This segment of Papa Stream contained habitat that primarily represented shallow riffle with acobble substrata.At the upstream end of the stream segment,there is a small, concrete weir that extendsacross the entire width of the stream bed(station 11+80). In this location, there was aperiphyton complex of Cladophora andSpirogyra covering the rocks. The presenceof Cladophora and Spirogyra was, in part, dueto the open canopy at this site. No solidwaste material was observed.Downstream of the concrete dam structure, the stream was heavily polluted with householdgarbage. There was visual evidence that this solid waste material had been dumped by someresidents living adjacent to the stream.FishTwo species of Stiphodon and two species of Sicyopterus were abundant in Papa Stream.Kuhlia spp. were common, but no anguillids were observed during the survey. Althoughgobies were well represented, other macrofaunal organisms were absent.InvertebratesMacrobrachium lar was the only crustacean documented in the stream. No neritids wereobserved along the stream segment. The lack of some species may have been due toelevational preferences of some organisms. Some organisms may be present at higherelevations of Papa Stream, Leele Stream, and Tauese Stream.There may be many factors that favor gobies over other taxa in Papa Stream. Long-termmonitoring at various elevations is needed to explain the abundance and diversity of organismsin this stream.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey are summarizedin Table 7-4. Genera are listed in order of descending abundance within their taxonomic group.TABLE 7-4SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED ALONG PAPA STREAMStream Location Fishes Crustaceans MolluscsFormer Navy weir site(approximately 1,180 feetupstream of Route 1 streamcrossing)Sicyopterus (2 spp.)Stiphodon (2 spp.)KuhliaMacrobrachium NoneAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-8

Source: Chong, 2000The relative abundance and diversity of fish and invertebrates along Papa Stream issummarized in Table 7-5. The characterization of relative abundance and diversity reflects ageneral comparison of the abundance and diversity of fish and invertebrates observed at onePapa Stream site with all 10 sites evaluated for the Wetland/Stream Restoration andEnhancement Plan. Papa Stream contained the highest density and diversity of gobies that wasobserved at all of the 10 sites.TABLE 7-5RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESPAPA STREAMFishes Crustaceans MolluscsAbundance High Medium LowDiversity High Low LowSource: Pedersen Planning Consultants, 2000LAND USES ADJACENT TO PAPA STREAMPapa Stream is situated within an upland residentialarea of Nuuuli Village. Approximately 11 singlefamily homes are constructed immediately adjacent tothe east and west banks of the stream. Vehicular roadsand trails from Route 1 provide access to these homes.A few piggeries were also located near the banks of thestream. In some cases, wastewater from thesepiggeries discharged into Papa Stream.Station 1+00 is located below Route 1 roadwaycorridor. This area contains a variety of commercialretail establishments.Solid waste discarded from the 11 residences poses thegreatest impact upon stream hydrology and aquatichabitat. The amount of solid waste material in variouslocations prevented the flow of surface runoff alongthe main stem of the stream.RIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESGeneralThree opportunities were identified for the restoration and enhancement of lower Papa Stream.The scope of these restoration and enhancement opportunities, and related implementationstrategies, are presented in the following paragraphs. The potential benefits and impactsderived from the implementation of the recommended strategies are subsequently evaluatedand compared in the following paragraphs.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-9

Opportunities and StrategiesOption 1: Clean Papa Stream and Enhance Riparian VegetationThe initial action associated with Option 1 is a significant cleanup of lower Papa Stream. Thecleanup should be made between the concrete weir at station 11+80 and the Route 1 crossingover Papa Stream.This effort will require the collection and disposal of a wide variety and large volume of solidwaste materials. Manual collection will be sufficient to collect much of this material.However, the use of a backhoe, front-end loader, or “cherry picker” will be necessary toretrieve some larger materials that have been indiscriminately dumped into the stream bed.Larger dump trucks will be required to haul larger materials to the Futiga landfill.One of the greater challenges of this initial effort will be to mobilize heavy equipment atselected locations along the stream bank. Available equipment from either the American SamoaPower Authority or the American Samoa Department of Public Works should be requested andused to support the cleanup effort.Following the initial stream cleanup, the American Samoa Community College, Land GrantProgram should initiate the planting of about 300 native riparian trees along the banks of PapaStream. This planting should include a combination of ifi (Tahitian chestnut) fau, laufala, andfalaga tree seedlings. The planting of more native riparian trees along Papa Stream representsan important resource management opportunities because these native riparian trees have rootsthat can help stabilize the soil on the banks of the stream. Propagated seedlings of these nativetrees may already be available at the ASCC Land Grant Program nursery.The ASCC Land Grant Program would encourage residents to participate in the planting ofthese trees along the east and west banks of the stream. ASCC Land Grant has considerableexperience with encouraging community participation through its Forestry StewardshipProgram. Colin Steele, ASCC/AHNR Project Forester, envisions that the enhancement ofriparian vegetation and related participation of residents can best be accomplished byproviding, at no charge, a total of 30 tree seedlings to each household along the stream.However, the “no charge” arrangement would be conditional to the resident’s agreement toplant the new trees within 30 feet of the stream bank (Steele, 1995). Consequently, randomwetland tree plantings would be made along the east and west sides of the 1,200-foot streamsegment.Option 2: Clean Stream, Improve Stream Hydrology, and Reduce Bank ErosionThe initial action associated with Option 2 is a significant cleanup of lower Papa Stream. Thecleanup should be made between the concrete weir at station 11+80 and the Route 1 crossingover Papa Stream.This effort will require the collection and disposal of a wide variety and large volume of solidwaste materials. Manual collection will be sufficient to collect much of this material.However, the use of a backhoe, front-end loader, or “cherry picker” will be necessary toretrieve some larger materials that have been indiscriminately dumped into the stream bed.Larger dump trucks will be required to haul larger materials to the Futiga landfill.Incoming stream flows from Tauese Stream discharge into Papa Stream via a 3-foot wide,concrete culvert. This culvert is situated between stations 5+00 and 6+00. Under full flowconditions, the culvert can convey approximately 140 cfs of stormwater runoff at a velocity ofabout 18 feet per second. The angle of flow introduction to Papa Stream and occasional higherAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-10

flow velocities have apparently generated excessive erosion along the east bank of Papa Streamand littered the stream bed with considerable amounts of rock and debris.Due to the erosive nature of soils along the stream bank, aggressive bank stabilization practicesshould be used to help improve stream hydrology and reduce the amount of future stream bankerosion. While various construction options are available, it recommended that the east bank ofPapa Stream be armored with basaltic rock and grouted with a concrete slurry along theupstream and downstream sides of the Tauese Stream discharge (Figure 7-3). This approachwill enable the construction of a strong bank structure without increasing the velocity ofdownstream stream flows.Option 3: Restore Stream Path Upstream of Project AreaOption 3 would design and construct stream improvements that would:• restore the former single, stream path some 700 to 800 feet upstream of station 11+80;• somewhat reduce stream velocities downstream of the basaltic wall that has generatedsignificant downstream bank erosion;• reduce further downstream bank erosion along east and west banks of Papa Stream; and,• provide potential opportunities for planting wetland trees such as ifi along the 100-150-footlength of the stream bank that has been impacted by stream modification.ASEPA/ASDOC would need to retain a professional engineer to design conceptual,preliminary, and final construction drawings, as well as preliminary cost estimates, for thisstream improvement project. Once funds are secured for this project, a building contractorwould be selected for construction of the proposed design.Comparative Benefits and ImpactsPPC’s evaluation of the three alternate restoration and enhancement strategies is summarized inTable 7-6. Option 1 provides somewhat greater benefits to wetland vegetation and fish andinvertebrate habitat for a reasonable cost. Option 2 provides some needed improvementsbetween station 5+00 and 6+00 that would help reduce bank erosion and potential floodingalong a portion of lower Papa Stream.Option 3 would address a significant bank erosion and stream hydrology upstream of theproject area. This project would provide some benefits to wetland vegetation, as well as fishand invertebrate habitat. However, the potential significant cost associated with this projectmakes this project less desirable despite its need.TABLE 7-6COMPARATIVE EVALUATIONWETLAND RESTORATION AND ENHANCEMENT OPPORTUNITIESLOWER PAPA STREAMOption Project Residential Subsistence Fish & Wetland/ StreamCost Land Uses Agriculture Invertebrate Riparian BankFlood Hazards& PropertyDamageHabitat Vegetation Stability1 LC LB NBC MB SB NBC LB2 MC NBC NBC MB LB NBC MB3 SC MB NBC LB LB NBC LBNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsLC Limited undesirable consequencesMB Moderate project benefitsMC Moderate undesirable consequencesLB Limited project benefitsSC Significant undesirable project impactsNBC No anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-11

Figure 7-3Option 2: Reduction of Erosion at East Bank of Papa StreamAmerican Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-12

Recommended Option and Estimated Project CostThe cleaning of the 1,200-foot segment of Papa Stream and the planting of additional riparianvegetation (Option 1) is recommended for implementation. This wetland restoration project isrecommended because the project can enhance wetland vegetation, as well as fish andinvertebrate habitat.The costs associated with this project would primarily be associated with the initial clearing,removal and disposal of solid waste material from the lower reach of Papa Stream. Thesubsequent collection and planting of ifi, fau, laufala, and falaga tree cuttings would be carriedout by the ASCC Land Grant Program.The estimated cost associated with the initial clearing of the 1,200-foot segment of Papa wouldbe $3,626 (Table 7-7). The planting of native riparian trees would cost an estimated $3,348(Table 7-8). Consequently, the total project is expected to cost approximately $6,974.TABLE 7-7PRELIMINARY COST ESTIMATECLEARING OF LOWER PAPA STREAM MOUTHLABORPersonnel Number Hours Hourly Rate ($) Cost ($)Supervisor 1 40 15 600Heavy Equip. Operator 1 40 13 520Laborer 4 40 6 960All Personnel 6 240 $2,080MATERIALSItem Quantity Unit Cost ($) Cost ($)Picks 3 15 45Sledge Hammers 3 25 75Shovel 3 22 66Weed-eaters 3 300 900Machetes 3 20 60Garbage Bags 50 boxes 5 250Wheel Barrows 3 50 150All Materials $1,546TOTAL LABOR AND MATERIALS $3,626Notes: Preliminary estimate assumes use of existing equipment owned by the ASG Department of Pubic WorksSource: Pedersen Planning Consultants, 2000American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-13

TABLE 7-8PRELIMINARY COST ESTIMATEPROPAGATION AND PLANTING OF NATIVE RIPARIAN TREESLOWER PAPA STREAMLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 24 8 192ASCC Field Crew Members 2 24 6 288All Personnel 4 176 $1,520MATERIALSItem Quantity Unit Cost ($) Cost ($)Native Riparian Trees 300 3 900Garbage Bags 40 boxes 5 200All Materials $1,100EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eater 1 300 300All Equipment $571TOTAL LABOR AND MATERIALS $3,191Notes: Preliminary estimate assumes use of existing equipment owned by the ASG Department of Public WorksSource: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the restoration of the lower reach ofPapa Stream should include the seasonal monitoring of selected resource characteristics andperiodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-14

Long term monitoring of the Papa Stream restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of stream flow;• potential impedances to stream discharge;• evidence of eroding stream bank areas;• potential failures or damages to gabion baskets or rock walls along the stream bank;• survival of planted, riparian trees;• potential flood damages to commercial and public facility properties;• changes in land uses immediately adjacent to the stream banks;• point-source discharges, e.g., storm water; and,• changes in the type and number of fish and invertebrates near station 1+00.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 7-9. A field work sheet or checklist, which can be used inthe field, is provided in Table 7-10.Future resource monitoring can be effectively performed through bi-annual site visits to lowerPapa Stream. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Nuuuli Village Council. Assumingthat residents cooperatively permit periodic access for long-term resource monitoring, fieldmonitoring should begin at the station 1+00 and extend 1,180 feet upstream. Futuremeasurements of changes in the stream channel trapezoid will require the continued use of thesame stream cross section stations used for the present study.Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS. PPC has provided digital files for the Wetland and Stream Restorationand Enhancement Plan that provide a departure point for locating future resource monitoringstations along lower Papa Stream.All photographs should be incorporated into the digital photo album developed by PPC inconjunction with the Wetland/Stream Restoration and Enhancement Plan. This will enable along-term comparison of resource information.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-15

TABLE 7-9LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANPAPA STREAMResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Station 1+00 through Station 11+80 Presence of stream flow or obstructions to storm flowHydrology1 x (April-Nov)Stream Channel Stream channel 1 x (Dec-March) Measure manually, using tape measure Papa Stream: 1180 feet upstream of Station Changes in dimensions of stream channel trapezoidcross sections 1 x (April-Nov) 1+00 at 100-foot intervalsStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually Papa Stream: 1180 feet upstream of Station Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, 1+00 manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of Papa Stream banks Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, discharges into the stream channel?incorporate data into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new riparian trees Stream banks between Station 1+00 and Number of plants that remainvegetation 1 x (April-Nov) Station 11+80Aquatic Fish Type and number 2 x (Dec-March) Collection of driftnet samples of outgoing 10 feet upstream of Station 1+00. Changes in diversity and abundance of fish andand Invertebrates of fish and 2 X (April-Nov) larvae for 3-4 hour evening periods. crustaceans.crustaceans(See report narrative.)Molluscs Type and number 2 x (Dec-March) Mark-recapture technology or quadrant 10 feet upstream of Station 1+00. Changes in diversity and abundance of molluscs.of molluscs 2 X (April-Nov) counts at night.

TABLE 7-10FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANPAPA STREAMDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):PAGE 1 of 3 PAGESPapa StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream between Station 1+00 and Station 11+80? Yes No2a Are stream flows continuing immediately downstream of Station 1+00? Yes Nob If no, what appears to be impeding stream discharge? Describe.STREAM CHANNEL MODIFICATIONS3 a Has the stream bank been altered and with what material has the alteration been made? Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map _____ Check, when field map is so marked.4 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked5 a Is there evidence of bank erosion? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Do you see evidence of a change in the stream flow path? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID7 Refer to page 2: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW RIPARIAN PLANTS8 Count number of surviving new riparian treesCHANGES IN LAND USE9 a Document type and number of new land uses within 100 feet of stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked10 a Do any existing land uses, within 100 feet of the stream channel, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL11 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial12 Locate discharge on field map ___ Check, when field map is so marked

TABLE 7-10 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND AND ENHANCEMENT PLANPAPA STREAMPAGE 2 of 3 PAGESFISH AND INVERTEBRATES13 Identify the type and number of fish and crustaceans observed via the collection of driftnet samples of outgoing larvae.Family Genus/Specie Number Observeda Fishb CrustaceansMOLLUSCS14 Identify the type and number of molluscs that were observed by mark-recapture technology or quadrant count.Family Genus/Specie Number Observed

TABLE 7-10 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANPAPA STREAMCHANGES IN STREAM CHANNEL TRAPEZOID7 For each trapezoid represented below, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.PAGE 3 of 3 PAGESStation PAPA STREAM Station PAPA STREAM1+ 00 E 8 +00 EA B A BC D C DFF2 + 00 E 9+00 EA B A BC D C DFF3 + 00 E 10+00 EA B A BC D C DFF4 + 00 E 11+00 EA B A BC D C DFF5 + 00 E 11+80 EA B AC D C DFF6 + 00 EABCFD7 + 00 EABCFD

More specific monitoring of stream fauna should be made along Papa Stream in the vicinity ofthe station 1+00. Such monitoring should include the collection of driftnet samples of outgoinglarvae, at least two times per month, for 3-4 hour evening periods. The driftnets (150-200 ųmmesh) should be attached to rebar pounded into the stream substrata, or simply suspended fromtrees or bridges to that the net is at the surface of the water. The samples would subsequentlybe preserved in ethanol. The type and number of fish and crustaceans should be enumeratedusing a dissecting microscope. Use of the dissecting microscope will likely require a 2-3 daytraining class and the necessary equipment.Molluscs should be monitored by mark-recapture methodology, or quadrant counts at nightsince most are primarily nocturnal. Some training in these techniques is recommended.Site MaintenanceThe initial cleanup of lower Papa Stream will represent an important first step toward longtermstream enhancement. However, the initial cleanup is of limited benefit if it is notassociated with the implementation of a long-term maintenance strategy.Periodic site maintenance should take place along lower Papa Stream approximately four timesper year. Household wastes along the 1,200 feet of Papa Stream (station 1+00 through station12+00) are expected to represent the primary focus of long-term site maintenance.A crew of 10 persons will be necessary to periodically collect and remove discarded solidwaste material from the 1,200-foot segment of Papa Stream. Periodic cleanups would occurshortly after significant rainfall and stormwater events. Machetes and a weed-eater will berequired to periodically trim vegetation along selected portions of the stream channel.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Papa Stream, Page 7-20

LOCATIONChapter EightSAUINO STREAMSauino Stream is generally situated north of Pala Lagoon along the southern coast of the Islandof Tutuila (Figure 8-1). A 600-foot long segment of Sauino Stream is examined in this study.This segment is situated south of Route 1 and about 330 feet upstream of the Sauino Streammouth (Figure 8-2).STREAM HYDROLOGYSources of Surface RunoffSauino Stream and two unnamed tributaries carry a portion of the surface runoff that drainsfrom south slopes of Leele Mountain. Sauino Stream originates at about the 1,000-foot contourand meanders through the middle of Nuuuli Village before discharging into Pala Lagoon.An unnamed tributary east of the main stem of Sauino Stream begins near the 600-footelevation. This tributary carries surface runoff from the west side of Suaavamuli Ridge andjoins the main stem of Sauino Stream at about the 40-foot contour.A third small tributary extends from Deluxe Cafe along Route 1 to its confluence with the mainstem of Sauino Stream near the eight-foot elevation. A portion of this tributary represents the600-foot segment investigated for this study.General Stream CharacteristicsDownstream of Route 1, the small Sauino Stream tributary channel is characterized by acombination of basaltic rock and a man-made, earth lined channel. Smaller rock, cobble, sand,muck, and decomposed organic material comprise the bottom of the stream channel.Cross-sections documented by PPC in November 1999 indicate that the width of the streamsegment (between east and west stream banks) ranges between five and 24 feet. The depth ofthe stream channel (between the top of bank to the bottom of the stream bed) along the northside of the stream tributary is between 2.5 and four feet. Along the south side of the tributary,the depth of the stream channel ranges between 2.5 and five feet below the stream bank.While some solid waste material was found discarded along the 600-foot stream segment inNovember 1999, the type and volume of wastes did not appear to impede stream flow. Largersurface flows generated from stormwater events can easily overtop the stream banks and spreadinto adjoining residential and agricultural land areas.Stream ModificationsThe 600-foot segment of Sauino Stream was modified by local residents in the late 1990’s tohelp prevent property damage associated with occasional flooding in the residential area(Fanene, 1999). No rock-filled gabions or other bank stabilization structures were observedalong the stream channel in November 1999.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-1

Figure 8-1Location MapSauino Stream DrainageAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-2

Figure 8-2Sauino Stream SegmentExisting ConditionsAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-3

Stream FlowsHistorical Stream FlowsIn 1996, the U.S. Geological Survey (USGS) published an estimated median stream flow of0.25 cubic feet per second (cfs) for Sauino Stream (Table 8-1). The median stream flowestimate was based upon historical stream flow measurements obtained from 17 intermittentstream flow measurements taken from a low-flow, partial-record station (No. 16942000)between 1959 and 1975. This station was situated approximately 0.6 mile upstream from theSauino Stream mouth (Wong, 1996).TABLE 8-1MEDIAN STREAM FLOW ESTIMATESAUINO STREAMStream USGSGageStationGage LocationSauino Stream 16942000 0.6 mile upstream ofSauino Stream mouthSource: Wong, 1996Stream FlowMeasurements(number)Continuous intermittentlybetween 1959-1975EstimatedMedian Flow(cfs)0.25Stormwater Discharges and Related Flood PotentialIn 1999, Pedersen Planning Consultants made a hydrologic analysis of potential stormwaterdischarges into Pala Lagoon that could be generated from a range of storm events (PedersenPlanning Consultants, 2000). Through hydrologic modeling, PPC determined that potentialstormwater discharges into the Pala Lagoon can range from 278 cubic feet per second (cfs) fora 2-year storm and about 777 cfs for a 100-year storm (Table 8-2).TABLE 8-2STORMWATER DISCHARGES FROM SAUINO STREAM INTO PALA LAGOON2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 2-Year Storm 10-Year Storm 50-Year Storm 100-Year StormSauino Stream 278 427 693 777Source: Pedersen Planning Consultants, 2000In November 1999, PPC also gathered cross-sectional data along the 600-foot Sauino Streamsegment to assess the capability of this stream segment to accommodate these stormwaterevents. Cross sections were recorded at 100-foot intervals along this stream segment.With the application of hydrologic modeling, PPC determined that the maximum flow capacityof Sauino Stream is 279 cubic feet per second (cfs). When compared with potential stormwaterdischarges for a 2, 10, 50, and 100-year storm events, it is clear that stormwater flows greaterthan a 2-year storm would exceed the capacity of Sauino Stream.The potential flood plain, associated with a 100-year storm event in Nuuuli, was mapped by theFederal Emergency Management Agency (FEMA) in May 1991. Available flood insurancerate maps prepared by FEMA suggest that residential properties along the north and southbanks of the 600-foot Sauino Stream segment could be flooded from a 100-year storm event.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-4

VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the lower Sauino Stream segmenton November 5, 1999. Mr. Whistler was part of a three-person field survey team organized byPedersen Planning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.The vegetation along the 600-foot Sauino Streamdiffers considerably between the north and southsides of the stream channel.Vegetation along the south side of the channelcontained maintained grasses such as vaolima(T-grass) and Kyllinga brevifolia. Lesseramounts of carpet grass (Axonopus compressus),Alternanthera sessilis, and Kyllinga nemoralis.A smaller banana plantation was also adjacent tothe south side of the channel. None of the grassor tree species were obligate or facultativewetland plants.The north side of the stream channel resembled more of a wetland environment. This area wasdominated by California grass, Job’s tears, T-grass, and Merremia umbellata. Job’s tears andCalifornia grass are both facultative wetland species.Vegetation TrendsPrior studies of the vegetation of along lower Sauino Stream were conducted by BiosystemsAnalysis, Inc. A brief mention was made of a “hummocky area” between South PacificTraders (now Laufou Shopping Center) and Lion’s Park.Within a species checklist, botanists noted that the “hummocky area” was dominated primarilyby vaolima (T-grass) and Merremia umbellata. Drier margins were dominated by beggar’s-tick(Bidens alba) and a sensitive plant vao fefe (Mimosa pindica). No meaningful correlation canbe made concerning historical vegetative trends since the more general location of the“hummocky area” is not comparable to the more specific stream segment along Sauino Stream.However, it is interesting to note that both vaolima (T-grass) and Merremia umbellata wereidentified by both surveys.In the absence of other plantings, the continued maintenance of grasses along the south side ofthe 600-foot stream segment will likely maintain the presence of existing grasses. The northside of the channel may also continue to support California grass and Job’s tears unless bananaplantations are established. Residential expansion is not expected in light of the flood potentialin the vicinity of the stream segment.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-5

AQUATIC FISH AND INVERTEBRATESGeneralOn November 5, 1999, Charles Chong of the PPC field survey team made observations ofaquatic fish and invertebrates along the 600-foot segment of lower Sauino Stream. Hisobservations are summarized in the following paragraphs.This segment of Sauino Stream represented a relatively narrow, earth-lined channel. A streamflow of about one to two cfs was observed during the survey. Rainfall had occurred during, atleast, one day prior to the survey.Dragon/damsel flies (Odonates) were abundant. These introduced insects may be consideredimportant for stream integrity (Steele, 2000).FishTwo species of fish were abundant along the stream channel. These species included Poeciliamexicana and Poecilia reticulata.InvertebratesNo crustaceans were documented along the entire stream channel segment.In American Samoa, each watershed is unique and can be expected to contain different aquaticorganisms. The variation depends upon surface water flow regimes, water quality, and othergeophysical characteristics. With perennial, unimpeded stream flow to the ocean, the wetlandcould possibly include some or all of the type of aquatic animals summarized in Appendix B.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey are summarizedin Table 8-3. Genera are listed in order of descending abundance within their taxonomic group.TABLE 8-3SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED ALONG SAUINO STREAMStream Location Fishes Crustaceans Molluscs600-foot stream segment Poecilia (2 spp.) None NoneSource: Chong, 2000The relative abundance and diversity of fish and invertebrates along the lower Sauino Streamsegment is summarized in Table 8-4. The characterization of relative abundance and diversityreflects a general comparison of the abundance and diversity of fish and invertebrates observedalong the Sauino Stream segment with all 10 sites evaluated for the Wetland/StreamRestoration and Enhancement Plan.The abundance and diversity of fish and molluscs were lower compared to the other 10 sitesinvestigated for the study.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-6

TABLE 8-4RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESLOWER SAUINO STREAM SEGMENTFishes Crustaceans MolluscsAbundance Low None LowDiversity Low None LowSource: Pedersen Planning Consultants, 2000LAND USES ADJACENT TOLOWER SAUINO STREAMThe lower Sauino Stream segment is situatedwithin a low-density residential area ofNuuuli Village. Approximately five singlefamily homes are constructed immediatelyadjacent to the north and south banks of thestream. One smaller banana plantation islocated along the south side of the 600-foot,stream channel segment.RIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESGeneralTwo opportunities were identified for the restoration and enhancement of lower Sauino Streamsegment. The scope of these restoration and enhancement opportunities, and relatedimplementation strategies, are presented in the following paragraphs. The potential benefitsand impacts derived from the implementation of the recommended strategies are subsequentlyevaluated and compared in the following paragraphs.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Opportunities and StrategiesOption 1: Construct a Detention PondOption 1 would incorporate the 600-foot stream segment within a larger, 9.1-acre detentionpond area (Figure 8-3). The intent of this option would primarily be to detain largerstormwater flows that can occasionally inundate portions of the adjoining residential area andreduce the amount of sediment discharge into Pala Lagoon. Secondarily, the project objectivewould be to establish more wetland vegetation in the vicinity of lower Sauino Stream.However, no new vegetation would be planted along the 600-foot stream segment.Construction of the detention area would initially require the excavation of the project area tothe 2.5-foot contour. Roughly five to six feet of soil would be excavated from the proposeddetention area.A five to six-foot high way would be constructed along the perimeter of the detention pond.The pond perimeter would extend approximately 4,250 feet. The wall would be constructedthrough the use of small bags of cement that would be hand-carried and placed along the pondperimeter. The maximum slide slope of the pond interior would contain a 4:1 slope.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-7

Figure 8-3Option 1: Construction of Detention PondAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-8

The wall would be back-filled with native soil to reduce the visual impact of the concrete bags,as well as afford the opportunity to plant ifi, other wetland trees, and some fruit trees. Treeswould be planted immediately adjacent to the pond perimeter along a 20-foot wide buffer.Wetland and fruit trees would further enhance the attractiveness of the detention area andincrease wetland vegetation in the vicinity of the stream. Planting of the wetland and fruit treeswould be accomplished by the ASCC Land Grant Program.A coral trail within the detention pond would enable pedestrian access within the adjoiningresidential area, as well as access to nearby commercial and recreational areas.Option 2: Plant Native Riparian Trees Along Stream BanksOption 2 would focus more specifically upon the 600-foot stream segment (Figure 8-4). Alongthe north and south stream banks, the American Samoa Community College, Land GrantProgram should initiate the planting of ifi (Tahitian chestnut) fau, laufala, and falaga.However, no trees would be planted between the south stream bank and the existing bananaplantation.The establishment of Tahitian chestnut and other native riparian trees along the stream bankrepresents an important opportunity because these trees contains roots that can help stabilizethe soil along the banks of the stream segment. Propagated seedlings of these native trees mayalready be available at the ASCC Land Grant Program nursery.The ASCC Land Grant Program would encourage residents to participate in the planting ofthese trees along the north and south banks of the stream. ASCC Land Grant has considerableexperience with encouraging community participation through its Forestry StewardshipProgram. Colin Steele, director of the Land Grant Program, envisions that the establishment ofnative riparian trees and the related participation of residents can best be accomplished byproviding, at no charge, a total of 30 tree seedlings to each household along the stream.However, the “no charge” arrangement would be conditional to the resident’s agreement toplant the new trees within 30 feet of the stream bank (Steele, 1995). Consequently, randomriparian tree plantings would be made along the north and south sides of the 600-foot streamsegment.Comparative Benefits and ImpactsPPC’s evaluation of the two alternate restoration and enhancement strategies is summarized inTable 8-5.Option 1 provides a significant opportunity for stormwater detention opportunity, as well as thereduction of flood hazards and property damages. This option would also provide limitedenhancement of riparian vegetation in the vicinity of Sauino Stream. At the same time, thisproject would generate the loss of some limited subsistence agriculture and would require asignificant public expenditure for project implementation.Option 2 would significantly improve riparian vegetation, help stabilize stream banks, andreduce the transport of sediments into Pala Lagoon for a nominal project cost. This projectwould not impact adjoining residential land uses or subsistence agricultural production.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-9

FIGURE 8-5OPTION 2: PLANT NATIVE RIPARIAN TREES ALONG STREAM BANKSAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-10

TABLE 8-5COMPARATIVE EVALUATIONRIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESLOWER SAUINO STREAM SEGMENTOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetland/RiparianVegetationStreamBankStabilityFloodHazards &PropertyDamage1 SC LC LC NBC LB SB SB2 SB LB NBC NBC SB NBC NBCNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsLCMB Moderate project benefitsMCLB Limited project benefitsSCNBC No anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000Recommended Option and Estimated Project CostLimited undesirable consequencesModerate undesirable consequencesSignificant undesirable projectimpactsThe planting of additional riparian vegetation (Option 2) along the 600-foot stream segment isrecommended for implementation. This wetland restoration project is recommended becausethe project can significantly enhance riparian vegetation, help stabilize stream banks, andreduce sedimentation in Pala Lagoon for a reasonable cost.The costs associated with this project would primarily be associated with the collection andplanting of 100 native riparian trees. The planting would include a combination of ifi, fau,laufala, and falaga tree cuttings that would be provided by the ASCC Land Grant Program.Some of these cuttings may already be available. The estimated cost for the planting of 100native riparian trees would be approximately $2,471 (Table 8-6).TABLE 8-6PRELIMINARY COST ESTIMATEPLANTING OF RIPARIAN TREES ALONG LOWER SAUINO STREAMLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 8 8 64ASCC Field Crew Members 2 8 6 96All Personnel 4 128 $1,200MATERIALSItem Quantity Unit Cost ($) Cost ($)Riparian Trees 100 3 300Garbage Bags 20 boxes 5 100All Materials $400EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $2,471Notes: Preliminary estimate assumes use of existing equipment that is owned by the ASG Department of Public WorksSource: Pedersen Planning Consultants, 2000American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-11

Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the enhancement of the 600-footSauino Stream segment should include the seasonal monitoring of selected resourcecharacteristics and periodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.Long term monitoring of the Sauino Stream restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of stream flow;• potential impedances to stream discharge;• evidence of eroding stream bank areas;• potential failures or damages to gabion baskets or rock walls along the stream bank;• survival of planted, riparian trees;• potential flood damages to commercial and public facility properties;• changes in land uses immediately adjacent to the stream banks;• point-source discharges, e.g., storm water; and,• changes in the type and number of fish and invertebrates near station 1+00.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 8-7. A field work sheet or checklist, which can be used inthe field, is provided in Table 8-8.Future resource monitoring can be effectively performed through bi-annual site visits to lowerSauino Stream. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-12

TABLE 8-7LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANSAUINO STREAMResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Station 1+00 through Station 6+00 Presence of stream flow or obstructions to stream flowHydrology1 x (April-Nov)Stream Channel Stream channel 1 x (Dec-March) Measure manually, using tape measure Sauino Stream: 500 feet upstream of Changes in dimensions of stream channel trapezoidcross sections 1 x (April-Nov) Station 1+00 at 100-foot intervalsStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually Sauino Stream: 500 feet upstream of Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, Station 1+00 manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of Sauino Stream Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, discharges into the stream channel?incorporate data into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new riparian Stream banks between Station 1+00 andNumber of plants that remainvegetation 1 x (April-Nov) trees Station 6+00Aquatic Fish Type and number 2 x (Dec-March) Collection of driftnet samples of outgoing 10 feet upstream of Station 1+00 Changes in diversity and abundance of fish andand Invertebrates of fish and 2 x (April-Nov) larvae for 3-4 hour evening periods. crustaceans.crustaceans(See report narrative for detail.)Molluscs Type and number 2 x (Dec-March) Mark-recapture technology or quadrant 10 feet upstream of Station 1+00 Changes in diversity and abundance of molluscs.of molluscs 2 x (April-Nov) counts at night.

TABLE 8-8FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANSAUINO STREAMDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):PAGE 1 of 3 PAGESSauino StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no")1 Is water flowing in the stream (between Station 1+00 and Station 6+00)? Yes No2a Are stream flows continuing immediately downstream of Station 1+00? Yes Nob If no, what appears to be impeding stream discharge? Describe.STREAM CHANNEL MODIFICATIONS3 a Has the stream bank been altered and with what material has the alteration been made? Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map. _____ Check, when field map is so marked.4 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked5 a Is there evidence of bank erosion? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Do you see evidence of a change in the stream flow path? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID7 Refer to page 3: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW RIPARIAN PLANTS8 a Count number of surviving new riparian treesb Count number of surviving new fruit treesCHANGES IN LAND USE9 a Document type and number of new land uses within 100 feet of Sauino Stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked10 a Do any existing land uses, within 100 feet of the stream channel, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL11 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial12 Locate discharge on field map ___ Check, when field map is so marked

TABLE 8-8 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANVAIPITO STREAMPAGE 2 of 3 PAGESFISH AND INVERTEBRATES13 Identify the type and number of fish observed via the collection of driftnet samples of outgoing larvae.Family Genus/Specie Number Observeda FishbCrustaceansMOLLUSCS14 Identify the type and number of molluscs that were observed by mark-recapture technology or quadrant counts.Family Genus/Specie Number Observed

TABLE 8-8 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANSAUINO STREAMCHANGES IN STREAM CHANNEL TRAPEZOID7 For each trapezoid represented below, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.PAGE 3 of 3 PAGESStationSauino Stream1+ 00 EABCFD2 + 00 EABCFD3 + 00 EABCFD4 + 00 EABCFD5 + 00 EABCFD6 + 00 EABCFD

Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Nuuuli Village Council. Assuming thatresidents cooperatively permit periodic access for long-term resource monitoring, fieldmonitoring should begin at the station 1+00 and extend 500 feet upstream (Figure 8-4). Futuremeasurements of changes in the stream channel trapezoid will require the continued use of thesame stream cross section stations used for the present study.Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS. PPC has provided digital files for the Wetland and Stream Restorationand Enhancement Plan that provide a departure point for locating future resource monitoringstations along lower Sauino Stream.Photographs made during field monitoring should be incorporated into the digital photo albumdeveloped by PPC in conjunction with the Wetland/Stream Restoration and Enhancement Plan.This will enable a long-term comparison of resource information.More specific monitoring of stream fauna should be made along Sauino Stream in the vicinityof the station 1+00. Such monitoring should include the collection of driftnet samples ofoutgoing larvae, at least two times per month, for 3-4 hour evening periods. The driftnets (150-200 ųm mesh) should be attached to rebar pounded into the stream substrata, or simplysuspended from trees or bridges to that the net is at the surface of the water. The sampleswould subsequently be preserved in ethanol. The type and number of fish and crustaceansshould be enumerated using a dissecting microscope. Use of the dissecting microscope willlikely require a 2-3 day training class and the necessary equipment for field monitoringpersonnel.Molluscs should be monitored by mark-recapture methodology, or quadrant counts at nightsince most are primarily nocturnal. Some training in these techniques is recommended for fieldmonitoring personnel.Site MaintenancePeriodic site maintenance should take place along the 600-foot stream segment approximatelyfour times per year. Household wastes along the 600-foot segment of Sauino Stream areexpected to represent the primary focus of long-term site maintenance.A crew of four persons will be necessary to periodically collect and remove discarded solidwaste material from the 600-foot segment of Sauino Stream. Periodic cleanups would occurshortly after significant rainfall and stormwater events. Machetes and weed-eaters will berequired to periodically trim vegetation along selected portions of the stream channel.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-17

LOCATIONChapter NineLEAFU STREAMLeafu Stream is generally situated in Leone Village along the southwest coast of the Island ofTutuila (Figure 9-1). The stream is accessible via Route 1, which is situated immediatelysouthwest of Leone Pala (Figure 9-2).The study area included the downstream segment of Leafu Stream that flows through theinhabited village area. In 1998, Pedersen Planning Consultants investigated this streamsegment in the context of potential stormwater management opportunities. In November 1999,PPC focused its field investigations more upon the lower 300 feet of Leafu Stream, as well asunnamed stream parallel and immediately west of Leafu Stream. ASG Land Grant Programand ASEPA representatives believed that some wetland and stream enhancement opportunitieswere more feasible in this area.STREAM HYDROLOGYSources of Surface RunoffLeafu Stream and its four branches drain approximately 875 acres of land area upslope ofLeone Village. The main stem of Leafu Stream, which extends up to the southwest side ofAoloaufou Village, originates near the 1,135-foot elevation.General Stream CharacteristicsImmediately upstream of Leone Pala, the Leafu Stream drainage becomes very different. Inthis area, Leafu Stream and an adjoining unnamed stream actually represent three to fourseparate stream channels that are interspersed with small transitory islands of land area. InNovember 1999, the variations in the topography and stream hydrology of this area wereextremely difficult to identify in light of dense herbaceous vegetation and standing water.Further upstream within the inhabited village area of Leone, the Leafu Stream channel isconsiderably more narrow. The stream represents a combination of basaltic rock and earthlined channel. Smaller rock, cobble, sand, grass, muck, and decomposed organic materialcomprise the bottom of the stream channel.Cross-sections were documented by PPC in May 1998 at three stream locations. Channeldepths ranged between two and nine feet below the top of the stream bank (Table 9-1). Thewidth of the stream segment (between east and west stream banks) ranges between 15 and 150feet. The greatest stream width was recorded at cross section L6 just upstream from LeonePala.Onsite surveys along Leafu Stream in May 1998 and November 1999 discovered limited tomoderate amounts of solid waste material within the stream bed. In some cases, the type and/orvolume of wastes appeared to impede stream flow.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-1

Figure 9-1Location MapLeafu StreamAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-2

Figure 9-2Leone Pala and 300-Foot Leafu Stream SegmentExisting ConditionsAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-3

TABLE 9-1MEASUREMENTS FROM SELECTED STREAM CROSS SECTIONS, LEAFU STREAMMAY 1998StationChannelWidth(from top ofbank - in feet)Width ofChannelBottom(feet)ChannelDepth(feet)Other CharacteristicsL1 N/A N/A 9 9-year resident reports stream flows remainwithin stream banksL2 20 10 5 Medium rock along bottomL3 15-20 3 N/A Very grassy bottomL4 27 15 2 Rocky bottom primarily comprised of small rock.Scouring observed underneath concrete bridgeL5 N/A N/A N/A Berm adjacent to stream provides someprotection to adjacent homesL6 150 UndefinedUndefinedWetland plant indicators within undefineddrainagewayL7 N/A N/A N/A Concrete-lined channel adjoining unfinished 2-story home on man-made fill areaSource: Pedersen Planning Consultants, 1998In the vicinity of L2, significant stream bank erosion was observed along the west bank ofLeafu Stream in both May, 1998 and November, 1999. Continued bank erosion in this areawas also evident by an increase in stream channel width that had expanded from 20 feet in May1998 to 27 feet in November 1999. A former pedestrian stream crossing, which was used togain access to homes on the west side of Leafu Stream, had been washed out by higher streamflows and increased bank erosion within an 18-month period.Stream ModificationsWithin the inhabited village area, there is evidence of some stream channel modifications.These modifications generally include the past construction of short reaches of basaltic orconcrete walls, or rock-filled gabions. These structures have apparently been constructed tokeep higher stormwater flows within the stream banks or to prevent flooding on adjoiningresidential properties.Stream FlowsIn 1996, the U.S. Geological Survey estimated generally comparable rates of median streamflow for two locations along Leafu Stream (Table 9-2). These estimates were based uponcontinuous and partial gage measurements of stream flow by the U.S. Geological Survey.TABLE 9-2MEDIAN STREAM FLOW ESTIMATESLEAFU STREAMUSGS GageGage LocationStation16934000 0.9 mile upstream from stream mouth;30 feet upstream of reservoir169335000 1.3 miles NE of Leone; 900 feetupstream of village intakeSource: Wong, 1996.Stream FlowMeasurements(number)EstimatedMedian Flow(cfs)36 2.61continuous Oct,1977-Sept,1986; 5 between 1987-19902.50American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-4

However, during and following heavier rainfall events, stream flow discharges along LeafuStream are significantly greater. For example, a maximum discharge of 400 cfs at station169335000 was recorded by USGS on December 3, 1984.Stormwater Discharges and Related Flood PotentialStormwater runoff discharges into the Leone Pala are primarily generated from heavier rainfallevents that occur within the Leafu Stream drainage. Computer modeling of the Leafu Streamdrainage by Pedersen Planning Consultants suggests potential stormwater flows range between2,350 cubic feet per second (cfs) for a 10-year storm event and 4,098 cfs for a 100-year storm(Table 9-3).TABLE 9-3STORMWATER RUNOFF DISCHARGES INTO LEONE PALA10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)Location 10-Year Storm 50-Year Storm 100-Year StormLeafu Stream Mouth 2,350 3,684 4,098Source: Pedersen Planning Consultants, 1998The potential flood plain associated with a 100-year storm event in Leone Village was mappedby the Federal Emergency Management Agency (FEMA) in May 1991. Available floodinsurance rate maps prepared by FEMA suggest that residential properties along the east andwest banks of Leafu Stream could be flooded from a 100-year storm event. The 100-year floodplain extends up to 400 feet west of Leafu Stream and up to 800 feet east of the main channel.VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the lower, 300-foot segment ofLeafu Stream on November 8 and 17, 1999. Mr. Whistler was part of a three-person fieldsurvey team organized by Pedersen Planning Consultants that observed wetland vegetation,habitat for aquatic fish and invertebrates, stream hydrology, as well as land uses within andadjacent to the wetland. His observations are summarized in the following paragraphs.The vegetation along the lower 300-foot Leafu Stream is inland from the more significantwetland areas in Leone Pala that include mangrove swamp near the ocean, swamp forests,disturbed freshwater marshes, and wetland taro patches. In November 1999, the inland area,between Leafu Stream and an unnamed stream parallel to Leafu Stream, was comprised ofstream banks and transitory islands in the stream channels that were covered with herbaceousvegetation. The vegetation characterizing this inland wetland area was highly disturbed.The stream banks of this inland area were largely dominated by wetland plants such asmauutoga (commelina or Commelina diffusa), willow primrose (Ludwigia octovalvis),California grass (Brachiaria mutica), Malay ginger (Costus speciosus), and fue saina (mile-aminutevine). Also present were lesser amounts of weeds such as balsam pear (Momordicacharantia), basket grass (Oplismenus compositus), palulu (Stictocardia tiliifolia), and dissotis(Dissotis rotundifolia), and crop plants such as manioka (cassava). Trees included ulu(breadfruit), coconut, and native beach hibiscus.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-5

The wetlands closer to the mouth of LeafuStream comprised a combination ofdisturbed marsh, cultivated marsh, freshwaterswamp forest, as well as smallercoconut and banana plantations. In addition,at least one smaller taro patch was located instanding water that was apparently notwithin the main stream channel. Asubstantial amount of Ludwigia hyssopifoliaand some fue saina (mile-a-minute vine)was observed on the stream banks.Taro was also growing in drier soils above the stream banks. In this area, taro plants weresurrounded by weeds more typical of disturbed, dry land.Southeast of a relatively new buildinghousing poultry, there were disturbedwetlands that were probably formerly usedfor taro production prior to the recent taroblight. The disturbed wetland area wasdominated in some places by a dense coverof California grass and mile-a-minute vine,as well as lesser amounts of commelina. Inother areas, mile-a-minute vine was presentwithout California grass. Scattered treesincluded beach hibiscus and ifi (Tahitianchestnut). Other less common herbaceousplants included Luffa cylindrica, Struchiumsparganophorum, Acmella uliginosa,selesele (Mariscus javanicus), and willowprimrose (Ludwigia octovalvis).Immediately inland of Leone Pala, there was a swamp forest that consisted of dense thickets ofbeach hibiscus. It appeared that limited vegetation was able to survive in the wet soil orstanding water in the shade of the hibiscus canopy. However, occasional clumps of saato(swamp fern) were observed just upstream of the mangroves in Leone Pala.Vegetation along portions of the inland Leafu Stream segment appeared to resemble anenvironment between marsh and swamp. These areas contained low patches of beach hibiscusand scattered coconut trees that were surrounded by selesele (Mariscus javanicus), swamp fern,fuapepe (blue rat’s tail), Ludwigia hyssopifolia, and Struchium sparganophorum.No substantive forest of ifi (Tahitian chestnut) or marsh areas dominated by native species wasobserved in the 300-foot stream segment upstream of Leone Pala. Plantations along the westmargin of the wetland contained banana and scattered coconut trees growing in wet soil (amarginal wetland area) that typically would be expected to be barren.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-6

Vegetation TrendsThe lower Leafu Stream drainage represents a wide flood plain containing narrow streamchannels. PPC expected this area to be dominated by lowland forest trees such as mamalava(Planchonella samoense), afa (Neonauclea forsteri), and asi toa (Syzygium inophylloides).Along the edges of the lowland, the presence of some falaga was expected with roots in or nextto the water. In later times, some ifi would be anticipated in the same position. However, theweedy herbaceous plants and human disturbance prevent these plants from returning to the site(Whistler, 2000).The disturbed marsh dominated by California grass, fue saina (mile-a-minute vine), andLudwigia hyssopifolia will probably remain since few native marsh species are present. Forexample, neither vao tuaniu (marsh fern) or utuutu (water chestnut) were recorded in thedisturbed marsh.The beach hibiscus swamp, which is a climax type of vegetation, will probably remain thesame unless significant changes occur in stream hydrology. Stream banks will likely continueto be dominated by alien weedy species except where residents stabilize stream banks withbasaltic rock or concrete walls.Taro will likely continue to be cultivated in this area. Greater taro production can be expectedas blight resistant varieties become more available.AQUATIC FISH AND INVERTEBRATESGeneralOn November 5, 1999, Charles Chong of thePPC field survey team made observations ofaquatic fish and invertebrates along lowerLeafu Stream. His observations aresummarized in the following paragraphs.One upstream and one downstream site weresurveyed. The upland site was at the crosssection location L2. The downstream site waslocated about 300 feet upstream of Leone Pala.FishA complete complement of sycidine gobies were present and abundant at the upland site.Kuhlia, Anguilla, and Poecilia spp. were common at this location, but more abundantdownstream. Eleotris and Awaous spp. were also observed downstream.While not observed at the upstream or downstream sites, Tilapia was documented in a branchof Leone Pala. It is likely that these fish are distributed throughout Leone Pala, as well asimmediately upstream of Leone Pala.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-7

InvertebratesIn terms of crustaceans, Macrobrachium lar and Paleomon spp. were abundant at both theupstream and downstream sites. Ptychognathus was also common at the upstream site whileMacrobrachium australe was common downstream.Two neritid snails were common upstream, but not recorded at the downstream survey site.Greater silt and sediment at the downstream site may be the reason neritid snails were notobserved downstream.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey are summarizedin Table 9-4. Genera are listed in order of descending abundance within their taxonomic group.TABLE 9-4SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED ALONG LEAFU STREAMStream Location Fishes Crustaceans MolluscsLowland approximately400-500 upstream of LeafuStream mouthKuhliaPoecilia (2 spp.)AnguillaEleotrisMacrobrachium(2 spp.)PaleomonNoneStation L2Source: Chong, 2000AwaousKuhliaSicyopterus (2 spp.)Stiphodon (2 spp.)Poecilia (2 spp.)AnguillaMacrobrachiumPaleomonUnidentified GraspidcrabNeritina(2 spp.)The relative abundance and diversity of fish and invertebrates along the lower and upper LeafuStream segments are summarized in Table 9-5. The characterization of relative abundance anddiversity reflects a general comparison of the abundance and diversity of fish and invertebratesobserved along lower and upper Leafu Stream segments with all 10 sites evaluated for theWetland/Stream Restoration and Enhancement Plan.Leafu Stream contained the greater bio-diversity of any of the streams surveyed for the overallstudy. The abundance and diversity of fish and crustaceans were higher compared to the other10 sites investigated for the study. The abundance of molluscs was moderate, but theirdiversity was higher.TABLE 9-5RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESLOWER LEAFU STREAMFishes Crustaceans MolluscsAbundance High High ModerateDiversity High High HighSource: Pedersen Planning Consultants, 2000American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-8

LAND USES ADJACENT TOLOWER LEAFU STREAMThe lower Leafu Stream segment is situated withina low-density residential area of Leone Village.Within the inhabited village area, approximately 30single family homes are constructed immediatelyadjacent to the east and west banks of the stream.Although most homes are set back 100-200 feetback from the stream channel. Portions of thestream bank also used for a few, smaller bananaplantations and some decorative landscaping.The paving of the vehicular trail immediately east of Leafu Stream in 1999 may generate somebank erosion along selected stream bank reaches. During construction of the roadimprovements, no drainage inlets were installed to direct road drainage into the stream.Consequently, road drainage following normal stormwater events has begun to form naturalflow paths to Leafu Stream along the road right-of-way and some stream banks along the eastbank of the stream.RIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESGeneralThree opportunities were identified for the restoration and enhancement of lower Leafu Stream.One option is located upstream in the vicinity of L2 segment. The other two options representriparian enhancement project within the 300-foot stream segment immediately upstream ofLeone Pala. The scope of these restoration and enhancement opportunities, and relatedimplementation strategies, are presented in the following paragraphs. The potential benefitsand impacts derived from the implementation of the recommended strategies are subsequentlyevaluated and compared in the following paragraphs.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Opportunities and StrategiesOption 1: Restore Stream Bank in Vicinity of L2Option 1 would construct rock-filled gabions along an eroded stream bank in the vicinity ofstation L2 (Figure 9-3). The intended objective of the proposed construction would be tostabilize failing or potentially erosive stream bank areas in order to reduce downstreamsedimentation.In the vicinity of L2, gabions would be installed along selected reaches of the east and westsides of the stream. A total of approximately 100-feet of gabions would be constructed at onemore sites in the immediate vicinity of L1. In 1999, PPC estimated that such improvementswould cost approximately $20,700.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-9

FIGURE 9-3OPTION 1: RESTORE STREAM BANKI IN VICINITY OF L1American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-10

Option 2: Construct Basaltic Wall, Stabilize East Stream Bank,and Enhance Riparian VegetationIn the vicinity of station L6, a trench would be excavated along 300 linear feet of the drainagearea. The trench would be located immediately west of existing residences on the east side ofthe Leafu Stream drainage (Figure 9-4).A basaltic rock wall would be constructed within the trench using wire gabions approximately4x3x10-feet in size. Presence of the wall would better define the east stream bank and helpdirect future stream flows. At the same time, the wall may also help reduce potential flooddamage from medium stream flows. However, stream hardening along the east stream bankcould also generate an increase in stream flow velocities during stormwater events.Some basaltic rock treatment would be made on the top and east side of the wall to ensure thatthe wall would be attractive and complement existing residential and subsistence agriculturaldevelopment. The wall would also be back-filled with native soil on the east side of the wall toreduce the visual impact of the wire gabions (Figure 9-4).West of the proposed wall, the east stream bank would be enhanced through the planting ofroughly 100 native riparian trees such as ifi (Tahitian chestnut) fau, laufala, and falaga. Suchplants would increase the stability of the east stream bank that adjoins residential properties.The propagation of seeds and/or collection of tree cuttings would be made by the ASCC LandGrant Program nursery and planted by Land Grant personnel in cooperation with locallandowners.Option 3: Stabilize East Stream Bank and Enhance Riparian VegetationOption 3 would be very similar to Option 2 except that no basaltic wall would be constructed tobetter define the margin of the east stream bank near L6. Otherwise, the same type and numberof native riparian trees would be planted along portions of the east stream bank near L6 (Figure9-5).The establishment of ifi (Tahitian chestnut), fau, laufala, and falaga and other native ripariantrees along the east stream would primarily help stabilize the east bank that adjoins residentialand subsistence agricultural land uses. The root systems associated with these trees containroots that can effectively help stabilize the soil.The propagation of seeds and/or collection of tree cuttings would be made by the ASCC LandGrant Program nursery and planted by Land Grant personnel in cooperation with locallandowners. However, the ASCC Land Grant Program may elect to encourage adjoiningresidents to participate in the planting of these trees along the east stream bank.ASCC Land Grant has considerable experience with encouraging community participationthrough its Forestry Stewardship Program. Colin Steele, ASCC/AHNR project forester,envisions that the establishment of native riparian trees and the related participation of residentscan best be accomplished by providing, at no charge, a total of 30 tree seedlings to eachhousehold along the stream. However, the “no charge” arrangement would be conditional tothe resident’s agreement to plant the new trees within 30 feet of the stream bank (Steele, 1995).Consequently, some 100 riparian tree plantings would be randomly planted along the east bank,roughly 300-550 feet upstream of the stream mouth.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-11

Figure 9-4Option 2: Construction of Basaltic Wall in Vicinity of Station L6American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-12

Figure 9-5:Stabilize East Stream Bank and Enhance Riparian VegetationAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-13

Comparative Benefits and ImpactsPPC’s evaluation of the three alternate restoration and enhancement strategies is summarized inTable 9-6. Options 2 and 3 primarily enhance bank stabilization and riparian vegetation. Bothof these options generate a comparable level of overall project benefits. However, Option 3 isrecommended to avoid the potential generation of increased stream velocities via theconstruction of a man-made wall along the east stream bank.Option 2 provides somewhat greater benefits in the reduction of potential flood damages withinthe adjoining residential area. However, during stormwater events, increased stream hardeningwould increase stream velocities in the lower Leafu Stream channel. In addition, the costsassociated with the implementation of Option 2 are somewhat greater.Option 1 also provides enhanced bank stabilization in the vicinity of station L2. Increased bankstabilization will help reduce downstream sedimentation, as well as provide some nominalbenefits to adjoining land uses.TABLE 9-6COMPARATIVE EVALUATIONRIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESLOWER LEAFU STREAM SEGMENTOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetland/RiparianVegetationStreamBankStabilityFloodHazards &PropertyDamage1 LC MB NBC LB NBC SB LB2 MC LB LB NBC SB SB MB3 LC LB LB NBC SB SB LBNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsMB Moderate project benefitsLB Limited project benefitsNBC No anticipated project benefits or undesirableconsequencesSource: Pedersen Planning Consultants, 2000LCMCSCLimited undesirable consequencesModerate undesirable consequencesSignificant undesirable projectimpactsRecommended Option and Estimated Project CostOption 3 is recommended for future stream enhancement.implementation would be approximately $2,471.The estimated cost ofThe estimated costs associated with this project would primarily be associated with thepropagation and planting of 100 ifi, fau, laufala, and falaga seedlings by the ASCC Land GrantProgram for $2,471 (Table 9-7).American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-14

TABLE 9-7PRELIMINARY COST ESTIMATEPROPAGATION AND PLANTING OF RIPARIAN TREESALONG LOWER LEAFU STREAMLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 8 8 64ASCC Field Crew Members 2 8 6 96All Personnel 4 128 $1,200MATERIALSItem Quantity Unit Cost ($) Cost ($)Riparian Trees 100 3 $300Garbage Bags 20 boxes 5 100All Materials $400EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment 8771TOTAL LABOR AND MATERIALS $2,471Notes: Preliminary estimate assumes use of existing equipment that is owned by the ASG Department of Public WorksSource: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the enhancement of the 300-footLeafu Stream segment should include the seasonal monitoring of selected resourcecharacteristics and periodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-15

Long term monitoring of the Leafu Stream restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of stream flow;• potential impedances to stream discharge;• evidence of eroding stream bank areas;• survival of planted, riparian trees;• potential flood damages to commercial and public facility properties;• changes in land uses immediately adjacent to the stream banks;• point-source discharges, e.g., storm water; and,• changes in the type and number of fish and invertebrates approximately 400-500 feetupstream from Leafu Stream mouth.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 9-8. A field work sheet or checklist, which can be used inthe field, is provided in Table 9-9.Future resource monitoring can be effectively performed through bi-annual site visits to lowerLeafu Stream. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Leone Village Council. Assuming thatresidents cooperatively permit periodic access for long-term resource monitoring, fieldmonitoring should begin at the stream mouth and continue about 300 feet upstream (Figure 9-4).Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS.PPC has provided digital files for the Wetland and Stream Restoration and Enhancement Planthat provide a departure point for locating future resource monitoring area along lower LeafuStream.Photographs made during field monitoring should be incorporated into the digital photo albumdeveloped by PPC in conjunction with the Wetland/Stream Restoration and Enhancement Plan.This will enable a long-term comparison of resource information.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-16

TABLE 9-8LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANLEAFU STREAMResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Leafu Stream mouth to 500 feet upstream Presence of stream flow or obstructions to stream flowHydrology 1 x (April-Nov) Visual observationStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually Leafu Stream mouth to 300 feet upstream Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new riparian trees Along east bank roughly 300-550 feet upstream Number of plants that remainvegetation 1 x (April-Nov) of Leafu Stream mouthWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of Leafu Stream bank Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, discharges into wetland or stream channels?incorporate data into GISAquatic Fish Type and number 2 x (Dec-March) Collection of driftnet samples of outgoing400-500 feet upstream of Leafu Sream mouth Changes in diversity and abundance of fish & crustaceans.and Invertebrates of fish and 2 x (April-Nov) larvae for 3-4 hour evening periodscrustaceans(See report narrative for detail.)Molluscs Type and number 2 x (Dec-March) Mark - recapture technology or 400-500 feet upstream of Leafu Stream mouth Changes in diversity and abundance of molluscs.of molluscs 2 x (April-Nov) quadrant counts at night

TABLE 9-9FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANLEAFU STREAMDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):PAGE 1 OF 2 PAGESLeafu StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no".)1 Is water flowing in the stream? Yes No2a Are stream flows entering Leone Pala? Yes Nob If no, what appears to be impeding stream discharge? Describe.STREAM CHANNEL MODIFICATIONS3 a Has the stream bank been altered and with what material has the alteration been made? Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map _____ Check, when field map is so marked.4 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked5 a Is there evidence of bank erosion? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Do you see evidence of a change in the stream flow path? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedSURVIVAL OF NEW RIPARIAN PLANTS7 Count number of surviving new riparian treesCHANGES IN LAND USE8 a Document type and number of new land uses within 100 feet of stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked9 a Do any existing land uses, within 100 feet of the stream channel, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL OR WETLAND10 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial11 Locate discharge on field map. ___ Check, when field map is so marked

TABLE 9-9 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANLEAFU STREAMPAGE 2 OF 2 PAGESFISH AND INVERTEBRATES12 Identify the type and number of fish observed via the collection of driftnet samples of outgoing larvae.Family Genus/Specie Number Observeda Fishb CrustaceansMOLLUSCS13 Identify the type and number of molluscs that were observed by mark-recapture technology or quadrant counts.Family Genus/Specie Number Observed

More specific monitoring of stream fauna should be made along lower Leafu Streamapproximately 400-500 feet upstream of the Leafu Stream mouth. Such monitoring shouldinclude the collection of driftnet samples of outgoing larvae, at least two times per month, for3-4 hour evening periods. The driftnets (150-200 ųm mesh) should be attached to rebarpounded into the stream substrata, or simply suspended from trees or bridges to that the net is atthe surface of the water. The samples would subsequently be preserved in ethanol. The typeand number of fish and crustaceans should be enumerated using a dissecting microscope. Useof the dissecting microscope will likely require a 2-3 day training class and the necessaryequipment.Molluscs should be monitored by mark-recapture methodology, or quadrant counts at nightsince most are primarily nocturnal. Some training in these techniques is recommended.Site MaintenancePeriodic site maintenance should take place along the 300-foot stream segment approximatelyfour times per year. Household and agricultural wastes along the 300-foot segment of LeafuStream are expected to represent the primary focus of long-term site maintenance.A crew of three persons will be necessary to periodically collect and remove discarded solidwaste material from the 300-foot segment of Leafu Stream. Periodic cleanups would occurshortly after significant rainfall and stormwater events. Machetes and weed-eaters will berequired to periodically trim vegetation along selected portions of the stream channel.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Leafu Stream, Page 9-20

Chapter TenASILI STREAMLOCATIONAsili Stream is located along the southwest coast of the Island of Tutuila (Figure 10-1). Thestream segment investigated for this study extends from the Asili Stream mouth to about 1,000feet upstream of the shoreline (Figure 10-2).STREAM HYDROLOGYSources of Surface RunoffThe Asili Stream drainage carries surface runoff from the south and southwest slopes of acentral plateau in west Tutuila that is situated west of Aoloaufou. This central plateau issituated at about the 1,200-foot elevation.Seven tributaries contribute runoff to the main stem of Asili Stream between the 180-foot and800-foot elevation. Downstream of these confluences, the main stem of the stream continuesdownslope, through Asili Village, to the adjoining shoreline.General Stream CharacteristicsStream cross-sections documented by PPC in November 1999 indicate that the width of thestream segment (between east and west stream banks) ranges between 17 and 43 feet (Figure10-2). The depth of the stream channel (between the top of bank to the bottom of the streambed) is between 2.0 and 7.5-feet along the east side of the stream. Along the west side of thestream, the depth of the stream channel ranges between 2 and 10 feet below the stream bank.The stream channel bed is composed of exposed basalt and larger boulders, smaller rockcobble, sand, and decomposed organic material. Rock and solid waste material are found atvarious points within the streambed, as well as along the banks of the stream. A sandystreambed is evident between the stream mouth and the Route 1 bridge.In November 1999, general stream channel characteristics exhibited signs of former streamdischarges that contained significant stream volume and velocity. Immediately above thevillage, residents informed PPC representatives that they have observed the flooding of themost upstream residential property along the west side of the stream. A survey of the streamchannel upstream of this property by PPC suggests that flooding has probably been generatedby larger basaltic boulders that have apparently been carried into the main stem of the streamduring more recent stormwater events. A small “island” of land area appeared to have recentlyformed along the west bank of the stream. The presence of larger boulders upstream may havemodified the former path of stream flow. With the change in stream flow path, storm flowsgradually bisected a portion of the west stream bank. Consequently, future stormwater flowsmay soon threaten the most upstream residence in Asili Village.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-1

Figure 10-1Location MapAsili Stream DrainageAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-2

Figure 10-2Asili Stream SegmentExisting ConditionsAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-3

A 75-foot reach of rock-filled gabions was observed along the east side of Asili Stream nearstation 9+00. Five gabion baskets were also documented in the vicinity of station 6+00 alongthe east side of the stream. Both sets of gabions were apparently constructed by residents tohelp prevent flooding from higher stream flows.Past flooding in the vicinity of station 4+00 was reported by one resident who recalled theflooding of one guest fale along the west bank of the stream (Maugaotega, 1999). Erosion ofthe stream bank was also evident in this location.Stream FlowsHistorical Stream FlowsThree stream gages have historically been established by the U.S. Geological Survey at variouspoints along Asili Stream (Table 10-1). The data gained from these stream gages provide aninsight of historical stream flows along Asili Stream.Between 1977 and 1986, a continuous-record gage (No. 16931500) was established at the 330-foot elevation. These measurements enabled USGS to calculate an estimated median flow of1.60 cubic feet per second (cfs).The same gage was operated as a partial-record site between 1987 and 1990. Extreme flowsrecorded during this period included a maximum discharge of 653 cfs on October 28, 1960 anda minimum of 0.20 cfs on August 6, 1983.Another partial record station (No. 16932500) was operated 100 feet upstream from the Route1 bridge between 1959 and 1990. Data generated from 34 measurements of stream flow wereused by USGS to estimate a median stream flow of 2.85 cfs (Wong, 1996).Various other one to two-day measurements of stream flow were made by USGS at variouspoints along Asili Stream. This data is not presented since more reliable data was obtainedfrom the three other stream gages (Table 10-1).TABLE 10-1MEDIAN STREAM FLOW ESTIMATEASILI STREAMUSGSGage StationGage Location16931500 0.8 mile upstream from streammouth at the 330-footelevation.16932000 0.5 mile upstream from theAsili Stream mouth.16932500 100 feet upstream of Route 1bridge.Source: Wong, 1996Stream FlowMeasurements(number)Continuously recordedbetween 1977-1986Estimated MedianFlow (cfs)1.6024 1.8534 2.85American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-4

Stormwater Discharges and Related Flood PotentialPedersen Planning Consultants made a hydrologic analysis of potential stormwater dischargesinto Asili Bay that could be generated from a range of storm. Through hydrologic modeling,PPC determined that potential stormwater discharges into Asili Bay can range from 620 cubicfeet per second (cfs) for a 2-year storm and about 1,606 cfs for a 100-year storm.Consequently, significant stream flows can be carried by Asili Stream for more frequent 2-yearevents, as well as less frequent 100-year storms.TABLE 10-2STORMWATER DISCHARGES FROM ASILI STREAM2,10,50, AND 100-YEAR STORM EVENTSIN CUBIC FEET PER SECOND (CFS)2-Year Storm 10-Year Storm 50-Year Storm 100-Year Storm620 938 1,468 1,606Source: Pedersen Planning Consultants, 2000In November 1999, PPC also gathered cross-sectional data along the 1,000-foot Asili Streamsegment to assess the capability of this stream segment to accommodate these stormwaterevents. Cross sections were recorded at 100-foot intervals along this stream segment.With the application of hydrologic modeling, PPC determined that potential stormwater flowsare greater than the capacity of most stream cross-sections (Table 10-3). One importantexception is the bridge culverts underneath Route 1 (station 3+00), which can accommodatestormwater flows of about 7,614 cfs. Consequently, the culverts underneath Route 1 cansupport potential flows from a 100-year storm event.TABLE 10-3CROSS-SECTIONAL ANALYSISALONG ASILI STREAM SEGMENTSlope of Stream(percent)Maximum Stream FlowThrough Cross Section(cfs)Station1+00 2.5 416.52+00 2.5 261.13+00 2.5 7,614.14+00 2.5 2,326.75+00 2.5 1,139.46+00 2.5 542.67+00 2.5 516.28+00 2.5 382.29+00 2.5 246.510+00 2.5 1,103.7Source: Pedersen Planning Consultants, 2000The potential flood plain associated with a 100-year storm event in Asili was mapped by theFederal Emergency Management Agency (FEMA) in May 1991. Available flood insuranceAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-5

ate maps prepared by FEMA suggest that residential properties along the east and west banksof the Asili Stream segment could be flooded from a 100-year storm event. FEMA alsoindicates that culvert underneath the Route 1 bridge is capable of containing flows from a 100-year storm event.Surface Water QualityDuring its November 1999 survey, PPC representatives informally met with Mr. Tago, avillage matai and member of the Fono. Mr. Tago reported that a significant amount ofsediment is discharged from Asili Stream during and following storm events. He believes thatturbid surface water discharges are due, in part, to erosion occurring in upland areas of thevillage that are used for the production of various subsistence crops.From October 1995 through May 1996, ASEPA conducted a water quality monitoring programat selected streams in Asili, Leone and Afono. This program was aimed at gaining a betterunderstanding of the source of sediments that impact surface water quality in the selectedstreams.Along each stream, weekly samples were obtained from stream locations that were adjacent todeveloped lands, a plantation, and undeveloped lands. Water samples were subsequentlyanalyzed to determine concentrations of total suspended solids (TSS), turbidity, total nutrients,and total phosphorus.Data obtained from this water quality monitoring program did not detect any significantdifference in water quality between the three types of stations along Asili Stream.Consequently, it remains unclear whether or not upstream plantations are contributing anysignificant amounts of eroded soil material into Asili Stream.VEGETATIONNovember, 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the Asili Stream segment onNovember 10, 1999. The walk-through survey was made within the stream banks from station1+00 and station 10+00 (Figure 10-2). Mr. Whistler was part of a three-person field surveyteam organized by Pedersen Planning Consultants that observed wetland vegetation, habitat foraquatic fish and invertebrates, stream hydrology, as well as land uses within and adjacent to thewetland. His observations are summarized in the following paragraphs.The vegetation of Asili Stream was comprised ofplants growing along the stream banks. One exceptionis the small “island” along the west stream bank that issituated immediately upstream of the most upstreamhome in Asili Village. The “island” was covered withdense herbaceous vegetation dominated by vao lima(T-grass). Less amounts of Malay ginger (Costusspeciosus) and taamu (giant taro) were interspersedwith banana trees and laupata (Macaranga harveyana). Taamu (giant taro, Alocasia macrorrhiza)The edge of subsistence plantations were adjacent to the stream banks in the vicinity of stations9+00 and 10+00. This area was dominated by plantation trees and weeds that are notcharacteristic of wetlands.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-6

Further downstream, the stream channel becomes more narrow and rocky. Native forest treesalong the east and west stream banks included afa (Neonauclea forsteri), fuafua (Kleinhoviahospita), fau (beach hibiscus), and maota mamala (Dysoxylum samoense). Wetland trees suchas ifi (Tahitian chestnut) and falaga (Barringtonia samoensis), as well as cultivated trees suchas ulu (breadfruit) also dominated this area. The ground cover consisted of basket grass, T-grass, and various weeds that are characteristic of upland vegetation.Lands adjacent to the lower portion of AsiliStream were more disturbed and containedcultivated trees such as vi (Polynesian plum),beach hibiscus, coconut, and breadfruit. Rockwalls, concrete walls, and rock-filled gabionbaskets reinforced most of the stream banks.Where man-made flood control structures werenot present, barren soils and soils covered withweeds were observed. Some landscaped lawnsalso were also established immediately abovethe stream banks.Between the stream mouth and the Route 1 bridge, a more lagoon type of environment wasevident. The seaward side of the stream channel contained modified littoral vegetation.Vegetation TrendsNo prior studies of the vegetation of Asili Stream have been conducted. Consequently, nocorrelation can be made concerning historical vegetative trends.The Asili Stream segment was probably once dominated by the same species that wereobserved upslope of the village. This vegetation comprises trees such as afa (Neonaucleaforsteri), fuafua (Kleinhovia hospita), fau, and maota mamala (Dysoxylum samoense).Wetland trees such as ifi and falaga are also present upstream of the village.The upper portion of the Asili Stream segment will probably remain in disturbed vegetation aslong as residents continue to harvest and use crops from subsistence plantations. The middleand lower portions of the stream segment are also expected to remain generally the same.However, the amount of vegetation along the stream banks may diminish somewhat if residentscontinue to build more flood control structures in response to future storm events.AQUATIC FISH AND INVERTEBRATESGeneralOn November 10, 1999, Charles Chong of the PPC field survey team made observations ofaquatic fish and invertebrates along the 1,000-foot segment of Asili Stream. His observationsare summarized in the following paragraphs.An overstory canopy covered much of the stream channel between the stream mouth and theinhabited residential area along the stream. Upstream of the village, the canopy over the streamwas more open.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-7

Stream flows observed during the survey represented a low flow condition of about 1-2 cfs.Surface waters appeared slightly milky upstream of the village.Immediately upstream of the inhabited villagearea, periphyton covered rocks within thestream. The periphyton complex, whichprimarily consisted of Cladophora andSpirogyra, was especially heavy since astormwater event had occurred only threeweeks prior to the survey. The heavier coverwas probably due to the increased amount ofsunlight reaching the water. However, theincreased amount of algae could also reflectnutrient inputs generated from upstreamagricultural activities.FishNear the stream mouth, Kuhlia spp. and Mugil were abundant. Four species of gobies werecommon. Eleotrids and a small anguillid were also observed in this area.Upstream of the village, gobies were also common. A plentiful population of Kuhlia was alsodocumented.InvertebratesTwo species of neritid snails were common along the stream segment. However, no Poeciliawere recorded.Macrobrachium lar and Paleomon spp. were abundant upstream of the inhabited village area.Relative Abundance and Diversity of Fish and InvertebratesA site specific summary of macrofaunal organisms observed during the survey are summarizedin Table 10-4. Genera are listed in order of descending abundance within their taxonomicgroup.The relative abundance and diversity of fish and invertebrates along Asili Stream issummarized in Table 10-5. The characterization of relative abundance and diversity reflects ageneral comparison of the abundance and diversity of fish and invertebrates observed along theAsili Stream segment will all other sites evaluated for the Wetland/Stream Restoration andEnhancement Plan.Asili Stream contained a moderate diversity and abundance of fish and invertebrates.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-8

TABLE 10-4SUMMARY OF MACROFAUNAL ORGANISMSOBSERVED ALONG ASILI STREAMStream Location Fishes Crustaceans MolluscsLowland approximately 150-feet upstream of Asili StreammouthKuhliaMugilSicyopterusEleotrisAwaousStiphodonStenogobiusEleotrisAnguillaMacrobrachium NoneStation 10+00Source: Chong, 2000KuhliaSicyopterusStiphodonMacrobrachiumPaleomonNeritina (2 spp.)TABLE 10-5RELATIVE ABUNDANCE AND DIVERSITY OF FISH AND INVERTEBRATESASILI STREAMFishes Crustaceans MolluscsAbundance Medium Medium MediumDiversity Medium Medium MediumSource: Pedersen Planning Consultants, 2000LAND USES ADJACENT TO ASILI STREAMMost of the Asili Stream segment is situated immediately adjacent to residential uses. Seawardof the Route 1 bridge, no residential uses were located adjacent to the stream.A few piggeries were also located near thebanks of the stream. In some cases, wastewaterfrom these piggeries discharged into AsiliStream.Solid waste discarded from the 12 residencesalong the stream poses the greatest impact uponstream hydrology and aquatic habitat.However, discarded solid waste material didnot appear to prevent the flow of surfacerunoff along the main stem of the stream.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-9

RIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESGeneralTwo opportunities were identified for the restoration and enhancement of lower Asili Stream.The scope of these restoration and enhancement opportunities, and related implementationstrategies, are presented in the following paragraphs. The potential benefits and impactsderived from the implementation of the recommended strategies are subsequently evaluatedand compared in the following paragraphs.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Opportunities and StrategiesOption 1: Clean Asili Stream and Enhance Riparian VegetationThe initial phase of Option 1 would represent the clean up of solid waste material within thebanks of Asili Stream. More specifically, the cleanup would occur between the stream mouthand station 10+00, the first 1,000 feet upstream of the stream mouth (Figure 10-3). This effortwill require the collection and disposal of a wide variety of solid waste materials. Manualcollection will be sufficient to collect of this material. A larger dump truck may be required tohaul larger materials to the Futiga landfill.Subsequently, The American Samoa Community College, Land Grant Program would initiatethe planting of 25 ifi (Tahitian chestnut) and 25 falaga trees along the banks of Asili Stream.Such plantings would be most beneficial along the margins of subsistence plantations that areadjacent to Asili Stream. Both ifi and falaga trees will help stabilize stream banks and helpdecrease potential downstream sedimentation. It is recommended that tree plantings are madewithin 25 feet of the east and west stream banks except where plantings interfere with adjoiningresidential land uses, or are not authorized by residents living adjacent to Asili Stream.Option 2: Restore Stream Flow Path Upstream of Inhabited Village AreaA change in the path of stream flow immediately upstream of the inhabited village area maygenerate future flood damages to, at least, one residence along the west bank of Asili Stream.Some corrective action will likely be required upstream of station 10+00 to restore the priorpath of stream flow.The construction of riprap upstream of the last residence in the village is recommended to helprestore the former path of stream flow along the west bank of the stream, as well as reducesedimentation that is being generated from the continuing erosion of the west stream bank.Larger basaltic boulders and smaller rock are readily available within the existing stream bed.Consequently, any construction effort would require a modest expense for the material neededto build the riprap. Labor and heavy equipment from the ASG Department of Public Workswould be required to haul selected rock material, from the stream bed to the west bank, andconstruct the riprap structure.Figure 10-3Option 1: Clean Asili Stream and Enhance Riparian VegetationAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-10

American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-11

Comparative Benefits and ImpactsPPC’s evaluation of the three alternate restoration and enhancement strategies is summarized inTable 10-6.TABLE 10-6COMPARATIVE EVALUATIONRIPARIAN RESTORATION AND ENHANCEMENT OPPORTUNITIESLOWER ASILI STREAMOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetland/RiparianVegetationStreamBankStabilityFloodHazards &PropertyDamage1 LC LB SB NBC SB MB NBC2 MC LB LB NBC NBC SB LBNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsLC Limited undesirable consequencesMB Moderate project benefitsMC Moderate undesirable consequencesLB Limited project benefitsSC Significant undesirable project impactsNBC No anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000Option 1 provides an initial cleanup of lower Asili Stream. The greater benefits associatedwith this option include the planting of ifi and falaga trees that will help stabilize stream banks,particularly in adjacent subsistence plantations. Greater stabilization of stream banks wouldhelp reduce bank erosion along lower Asili Stream. Project costs would be somewhat less thanthose required to implement Option 2.Option 2 would also address significant bank erosion and changes in stream hydrology in thevicinity of station 10+00. This project would provide needed stream stabilization along thewest bank of the stream and help restore the flow path of Asili Stream in this area. Oneresidence immediately downstream of this proposed improvement would benefit from potentialproperty damages that may occur if needed stream bank stabilization is not constructed.Recommended Option and Estimated Project CostThe cleaning of the 1,000-foot segment of Asili Stream and the planting of additional riparianvegetation (Option 1) is recommended for implementation. This wetland restoration project isrecommended because the project can enhance wetland vegetation and stabilize stream banksadjacent to smaller subsistence plantations.The costs associated with this project would primarily be associated with the initial clearing,removal and disposal of solid waste material from the lower reach of Asili Stream, as well asthe subsequent collection and planting of ifi and falaga tree cuttings by the ASCC Land GrantProgram.The estimated cost associated with the initial clearing of the 1,000-foot segment of lower AsiliStream is $3,126 (Table 10-7). The propagation and planting of 50 native riparian trees willcost an estimated $2,2 41 (Table 10-8). Consequently, the total estimated project cost would be$5,367.TABLE 10-7PRELIMINARY COST ESTIMATEAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-12

CLEAN-UP OF LOWER ASILI STREAMLABORPersonnel Number Hours Hourly Rate ($) Cost ($)Supervisor 1 24 15 360Heavy Equipment Operator 1 24 13 312Laborer 4 24 6 576All Personnel 6 144 $1,248MATERIALSItem Quantity Unit Cost ($) Cost ($)Picks 4 15 60Sledge Hammers 4 25 100Shovel 4 22 88Weed-eaters 4 300 1,200Machetes 4 20 80Garbage Bags 30 boxes 5 150Wheel Barrows 4 50 200All Materials $1,878TOTAL LABOR AND MATERIALS $3,126Notes: Preliminary estimate assumes use of existing equipment that is owned by the ASG Department of Public WorksSource: Pedersen Planning Consultants, 2000TABLE 10-8PRELIMINARY COST ESTIMATEPROPAGATION AND PLANTING OF NATIVE RIPARIAN TREESLOWER ASILI STREAMLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 4 8 32ASCC Field Crew Members 2 4 6 48All Personnel 4 116 $1,120MATERIALSItem Quantity Unit Cost ($) Cost ($)Native Riparian Trees 50 3 150Garbage Bags 20 boxes 5 100All Materials $250EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $2,241Notes: Preliminary estimate assumes use of existing equipment that is owned by the ASG Department of Public WorksSource: Pedersen Planning Consultants, 2000Long-Term Monitoring and Site Maintenance RequirementsAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-13

Long-term resource management activities associated with the restoration of the lower AsiliStream should include the seasonal monitoring of selected resource characteristics andperiodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.Long term monitoring of the Asili Stream restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of stream flow;• potential impedances to stream discharge;• evidence of eroding stream bank areas;• potential failures or damages to gabion baskets or rock walls along the stream bank;• survival of planted, riparian trees;• potential flood damages to commercial and public facility properties;• changes in land uses immediately adjacent to the stream banks;• point-source discharges, e.g., wastewater from piggeries; and,• changes in the type and number of fish and invertebrates approximately 150 feetupstream from Asili Stream mouth.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 10-9. A field work sheet or checklist, which can be usedin the field, is provided in Table 10-10.Future resource monitoring can be effectively performed through bi-annual site visits to lowerAsili Stream. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-14

TABLE 10-9LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANASILI STREAMResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Stream Flow 1 x (Dec-March) Visual observation Station 1+00 through Station 10+00 Presence of stream flow or obstructions to stream flowHydrology1 x (April-Nov)Stream Channel Stream channel 1 x (Dec-March) Measure manually, using tape measure Asili Stream: 1000 feet upstream of stream Changes in dimensions of stream channel trapezoidcross sections 1 x (April-Nov) mouth at 100-foot intervalsStream Modifications Changes to 1 x (Dec-March) Take digital photos, measure manually Asili Stream: 1000 feet upstream of stream Evidence of bank erosion, changes in flow path, or newstream banks 1 x (April-Nov) using tape measure, record type & size, mouth manmade structures along stream bank (e.g., rock walls)locate changes on map, incorporatedata into GISWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of Asili Stream between Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on map, Station 1+00 through Station 10+00 discharges into the stream channels?incorporate data into GISVegetation Survival of new 1 x (Dec-March) Take visual count of new riparian trees Between stream mouth and Station 10+00 Number of plants that remainriparian trees 1 x (April-Nov) upstreamAquatic Fish Type and number 2 x (Dec-March) Collection of driftnet samples of outgoing 150 feet upstream of Station 1+00. Changes in diversity and abundance of fish andand Invertebrates of fish and 2 x (April-Nov) larvae for 3-4 hour evening periods. crustaceans.crustaceans(See report narrative for detail.)Molluscs Type and number 2 x (Dec-March) Mark-recapture technology or quadrant 150 feet upstream of Station 1+00 Changes in diversity and abundance of molluscs.of molluscs 2 x (April-Nov) counts at night.

TABLE 10-10FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANASILI STREAMDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):PAGE 1 of 3 PAGESAsili StreamSTREAM AND WETLAND HYDROLOGY(Circle "yes" or "no")1 Is water flowing in the stream (between Station 1+00 and Station 10+00)? Yes No2a Are stream flows entering the nearshore waters? Yes Nob If no, what appears to be impeding stream discharge? Describe.STREAM CHANNEL MODIFICATIONS3 a Has the stream bank been altered and with what material has the alteration been made? Yes No___ Basaltic rock wall___ Concrete wall___ Rock-filled gabions___ Other, please describe:b If alteration has occurred, locate on field map. _____ Check, when field map is so marked.4 a Do existing rock walls, concrete walls or gabions appear to have been damaged from pastor recent stormwater events? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked5 a Is there evidence of bank erosion? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so marked6 a Do you see evidence of a change in the stream flow path? Yes Nob If so, where? (locate on field map) _____ Check, when field map is so markedCHANGES IN STREAM CHANNEL TRAPEZOID7 Refer to page 3: For each trapezoid represented, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.SURVIVAL OF NEW WETLAND PLANTS8 a Count number of surviving new mangrove treesb Count number of surviving new fruit treesc Count number of new coastal plantsd Count number of surviving littoral plantsCHANGES IN LAND USE9 a Document type and number of new land uses within 100 feet of stream channel.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked10 a Do any existing land uses, within 100 feet of the stream channel, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO STREAM CHANNEL11 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial12 Locate discharge on field map ___ Check, when field map is so marked

TABLE 10-10 (Continued)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANASILI STREAMPAGE 2 of 3 PAGESFISH AND INVERTEBRATES13 Identify the type and number of fish observed via the collection of driftnet samples of outgoing larvae.Family Genus/Specie Number Observeda FishbCrustaceansMOLLUSCS14 Identify the type and number of molluscs that were observed by mark-recapture technology or quadrant counts.Family Genus/Specie Number Observed

TABLE 10-10 (CONTINUED)FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANASILI STREAMPAGE 3 of 3 PAGESCHANGES IN STREAM CHANNEL TRAPEZOID7 For each trapezoid represented below, measure the distances between 1) Points A and B,2) Points C and D, and 3) Points E and F. Write in the measurement on each trapezoid.Station Asili Stream Station Asili Stream1+ 00 E 8+ 00 EA B A BC D C DFF2 + 00 E 9+ 00 EA B A BC D C DFF3 + 00 E 10+ 00 EA B A BC D C DFF4 + 00 EABCFD5 + 00 EABCFD6 + 00 EABCFD7 + 00 EABCFD

Vehicular and pedestrian access to selected monitoring stations is largely dependent upon thecooperation and authorization of local residents and the Asili Village Council. Assuming thatresidents cooperatively permit periodic access for long-term resource monitoring, fieldmonitoring should begin at station 1+00 and continue upstream to station 10+00 (Figure 10-3).Recommended monitoring stations or sites should be used consistently unless unanticipatedevents, new land uses, or access issues prevent continued use. When necessary, changes in thelocation of monitoring stations should be documented and spatially located within theAmerican Samoa GIS.PPC has provided digital files for the Wetland and Stream Restoration and Enhancement Planthat provide a departure point for locating future resource monitoring area along lower AsiliStream.Photographs made during field monitoring should be incorporated into the digital photo albumdeveloped by PPC in conjunction with the Wetland/Stream Restoration and Enhancement Plan.This will enable a long-term comparison of resource information.Measurements should also be made of the stream trapezoid to more specifically quantifychanges in stream hydrology. In essence, these measurements would be made at the samecross-section stations (stations 1+00 through 10+00) used for this study (Figure 10-2 and Table10-10):More specific monitoring of stream fauna should be made approximately 150 feet upstream ofthe Asili Stream mouth. Such monitoring should include the collection of driftnet samples ofoutgoing larvae, at least two times per month, for 3-4 hour evening periods. The driftnets (150-200 ųm mesh) should be attached to rebar pounded into the stream substrata, or simplysuspended from trees or bridges to that the net is at the surface of the water. The sampleswould subsequently be preserved in ethanol. The type and number of fish and crustaceansshould be enumerated using a dissecting microscope. Use of the dissecting microscope willlikely require a 2-3 day training class and the necessary equipment.Molluscs should be monitored by mark-recapture methodology, or quadrant counts at nightsince most are primarily nocturnal. Some training in these techniques is recommended.Site MaintenanceThe initial cleanup of lower Asili Stream will represent an important first step toward longtermstream enhancement. However, the initial cleanup is of limited benefit if it is notconnected to the implementation of a long-term maintenance strategy.Periodic site maintenance should take place along lower Asili Stream approximately four timesper year. Household wastes along the 1,000 feet of Asili Stream are expected to represent theprimary focus of long-term site maintenance.A crew of 8 persons will be necessary to periodically collect and remove discarded solid wastematerial from the 1,000-foot segment of Asili Stream. Periodic cleanups would occur shortlyafter significant rainfall and stormwater events. Machetes and weed-eaters will be required toperiodically trim vegetation along selected portions of the stream channel.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Asili Stream, Page 10-19

Chapter ElevenFUSI WETLANDLOCATIONFusi Village is located along the southwestcoast of the Island of Tau (Figure 11-1).The Fusi wetland is located immediatelyupland of Tau Harbor and the primaryshoreline vehicular trail along the westcoast of Tau (Figure 11-2). Past studiessuggest that this site comprisesapproximately 1.45 acres of wetland(Biosystems Analysis, 1993).WETLAND HYDROLOGYSources of Surface Runoff to the Fusi WetlandField observations by Pedersen Planning Consultants in November 1999 discovered that thereare no streams that discharge to the wetland. Available topographic maps also confirm that nostream or surface water bodies are connected hydrologically to the Fusi wetland.However, limited surface water (less than one cfs) was observed entering the north side of thewetland via sheet flow drainage from the steeper slopes east of the wetland. In addition,conditions within one or two ponded water areas within the wetland suggested the possiblehydrologic connection to a fresh-water spring.The Fusi wetland is situated within a few hundred feet of the shoreline and nearshore waters.However, no hydrologic outlet was detected during the survey. One west Tau resident alsoconfirmed that no outlet was present (Sega, 1999).Stormwater Discharges and Related Flood PotentialThere is no significant flood potential in the vicinity of the Fusi wetland. The entire Island ofTau was mapped by the Federal Emergency Management Agency (FEMA) in May 1991 toidentify potential 100-year flood plain areas. Available flood insurance rate maps indicate thatthe entire island is zone “x”. This designation signifies areas that are located outside of the500-year flood plain. Consequently, potential stormwater discharges within the Fusi wetlandand adjoining residential area are not anticipated.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-1

Figure 11-1Location MapFusi WetlandAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-2

Figure 11-2Fusi WetlandExisting ConditionsAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-3

WETLAND VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the Fusi wetland on November 9,1999. Mr. Whistler was part of a three-person field survey team organized by PedersenPlanning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.The north and west boundaries of the wetland are covered with disturbed vegetation anddominated by alien weeds. The south side of the wetland represents secondary forest/plantationthat is associated with an occupied house site.The underlying soils of the wetland contain a significant volume and wide variety of solidwaste material. Much of the material was apparently hauled to this site in the aftermath ofHurricane Val in December 1991.Fresh-Water SwampMost of the site was covered with a thicket offau (beach hibiscus). The dominance of thisspecie and saturated soils indicate that thiswetland should be classified as a fresh-waterswamp. Beach hibiscus was the only maturetree found over most of the wetland. However,saplings of lowland forest trees such as maotamamala (Dysoxylum samoense), afa(Neonauclea forsteri), nonu (Indian mulberry),and oa (Bischofia javanica) were also present.The perimeter of the wetland was dominated bydisturbed areas and secondary scrub.The surface of the swamp was relatively devoid of vegetation. The most common species wassaato (swamp fern), which probably covered less than five percent of the ground. Otherground cover species included marsh fern (Cyclosorus interruptus) and umbrella sedge(Cyperus alternifolius), as well as many other species observed only once or twice. The mostcommon epiphyte was the fern lau magamaga (Phymatosorus grossus) and lesser amounts oflaugapapa (bird’s nest fern).The adder’s-tongue fern (Ophioglossum reticulatum), which was listed as a rare plant ofconcern in a recent U.S. Fish and Wildlife Service survey, was found in the fresh-water swampon several low, moss-covered mounds or rock outcroppings. This species is known inAmerican Samoa only from several collections in the higher elevations of Laufuti Stream onthe south side of Tau, as well as from a single collection on Tutuila around 1860.Disturbed MarshThe southern part of the wetland is a disturbed marsh. Immediately adjacent to the beachhibiscus thicket is a disturbed marsh that is dominated by fue saina (mile-a-minute vine),willow primrose (Ludwigia octovalvis), as well as lesser amounts of pasio vao (love-in-a-mist)and palulu (Stictocardia tiliifolia). Fue saina and willow primrose are characteristic ofwetlands; the latter two weed species are not.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-4

South of this narrow zone and north of the plantation area behind the occupied house, there wasa small taro plantation growing on an artificial island delineated by rock embankments. Themost common weed among the taro plants was aatasi (Polynesian cress), a plant ofconsiderable importance in traditional Samoan medicine. However, no tamole vai was found inthis area.Vegetation TrendsIn 1993, Biosystems Analysis, Inc. recorded beach hibiscus as the dominant plant within thewetland. Beach hibiscus is a swamp species rather than a marsh species; swamps are typicallydominated by trees while marshes are dominated by herbs. Six years later, beach hibiscus hadtaken over most of the wetland in November 1999. Increased shade within the wetlandeliminated the typically shade-tolerant marsh species. Only a small amount of swamp fern andeven less marsh fern was present in the wetland. No water chestnut was documented.In November 1999, no falaga (Barringtonia samoensis) or ifi (Tahitian chestnut), which aretrees characteristic of wetlands on the Island of Tutuila, were recorded by the PPC survey team.PPC believes that the Fusi wetland margin may have once dominated by fau and falaga. Afterthe arrival of humans on Tau, ifi may also have been present. These large-seed species wouldnot easily disperse to the site without human intervention.The wettest areas of the wetland are not conducive to the growth of swamp forest as herbsdominate. Consequently, the wetland interior is a marsh rather than a swamp. Marsh specieswould typically include marsh species such as utuutu (water chestnut) and vao tuaniu (marshfern).This wetland was probably once under cultivation. Surface runoff and/or a spring furnishedwater needed for past taro cultivation. When cultivation discontinued, the wetland became adisturbed marsh. Whistler observed a disturbed marsh condition in 1976; willow primrose wasdocumented within the site at that time.In the absence of human intervention, it is expected that beach hibiscus swamp forest willremain dominant for a long time. The only possible competition might come from the saplings,e.g., afa. However, only afa is often associated with wetlands. Consequently, a few scatteredlowland forest trees may gain a precarious foothold in places with a slightly higher elevation, oron rock outcrops.AQUATIC FISH AND INVERTEBRATESGeneralOn November 9, 1999, Charles Chong of the PPC field survey team made observations of theFusi wetland. His observations are summarized in the following paragraphs.No flowing water was observed within the Fusi wetland. There was standing water in severalpools under heavy foliage. A thick layer of allochthonous material had collected on top of asignificant volume of solid wastes below these pools. Because of the heavy canopy and solidwaste material below the pools, visibility was limited. However, no macrofaunal organismswere observed during the survey.Onsite observations indicate that water within the pools was percolating into the substrata andpossibly seeping into the nearshore waters of nearby Tau Harbor. A noticeable fresh-water lenswithin the harbor was observed via snorkeling within the harbor waters.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-5

The lack of stream flow entering the Fusi wetland, as well as no hydrologic outlet, to thenearshore waters prevents the habitation of aquatic fish and invertebrates within the wetland.Aquatic species could only be humanly introduced in the absence of a hydrologic connection toan upland stream or outlet to the nearshore waters.Relative Abundance and Diversity of Fish and InvertebratesThe relative abundance and diversity of fish and invertebrates observed within the Fusi wetlandare summarized in Table 11-1. The characterization of relative abundance and diversityreflects the observation of no fishes, crustaceans, or molluscs. Consequently, the abundanceand diversity of fish and invertebrates at the Fusi wetland are clearly less than those observedat all 10 sites evaluated for the Wetland/Stream Restoration and Enhancement Plan.TABLE 11-1RELATIVE ABUNDANCE AND DIVERSITY OF FISHAND INVERTEBRATES IN FUSI WETLANDFishes Crustaceans MolluscsAbundance None None NoneDiversity None None NoneSource: Pedersen Planning Consultants, 2000LAND USES IN THE VICINITY OF FUSI WETLANDAs mentioned earlier, the Fusi wetland hasbeen used for the disposal of various types ofsolid waste material. Much of the wetlandapparently contains residential andcommercial building materials that werehauled to the wetland in the aftermath ofHurricane Val in 1991. Several homes aresituated northwest of the wetland; oneadditional residence is located on thesoutheast side.Solid waste in Fusi wetlandTau Harbor is located immediately west ofthe wetland. Several small fishing boats areregularly moored within the harbor.Fishing boats in Tau HarborAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-6

WETLAND RESTORATION AND ENHANCEMENT STRATEGIESGeneralThere are two potential opportunities for the restoration and enhancement of the Fusi wetland.The scope of these restoration and enhancement opportunities and related implementationstrategies are presented in the following paragraphs.The potential benefits and impacts derived from the implementation of each strategy aresubsequently compared and evaluated. This analysis provides the basis for the selection of arecommended restoration or enhancement strategy.Preliminary cost estimates are presented for the implementation of the recommended strategy.Long-term monitoring and site maintenance requirements associated with the recommendedstrategy are also identified.Alternate Opportunities and StrategiesOption 1: Remove Solid Waste Material and Plant Wetland Marsh VegetationBiosystems Analysis, Inc. suggested in 1993 that the best opportunity for wetland restoration inthe Manua Islands was restoration of the Fusi wetland. The initial requirement for therestoration of the former coastal marsh would be the excavation of solid waste material via theprimary use of bulldozers, front-end loaders, and trucks (Figure 11-3). Required heavyequipment can probably be obtained from Tau-based, operating divisions of ASPA and/or theASG Department of Public Works. Secondarily, some smaller materials would be retrievedmanually. Subsequently, excavated material would be hauled by truck to the public solid wastelandfill situated northeast of Tau High School.Bulldozers and front-end loaders would subsequently be used to re-grade the site to thecontours that were generally identified on 1990 topographic maps for the Fusi area and removeremaining portions of the beach hibiscus thicket. ASCC Land Grant personnel would be usedto plant some 50 utuutu (water chestnut), 25 vao tuaniu (marsh fern), 25 selesele(Rhynchospora corymbosa), and 25 saato (swamp fern).Option 2: Remove Solid Waste Material and Establish Taro ProductionSimilar to Option 1, the initial action associated with the restoration of the former coastal marshwould be the excavation of solid waste material via the primary use of bulldozers, front-endloaders, and trucks. Required heavy equipment can probably be obtained from Tau-based,operating divisions of ASPA and/or the ASG Department of Public Works. Secondarily, somesmaller materials would be retrieved manually. Subsequently, excavated material would behauled by truck to the public solid waste landfill situated northeast of Tau High School.Existing vegetation within the wetland would also be cleared to enable use of the wetland forfuture taro production. Water required from taro production would be derived from rainfall, aswell as limited surface water flows from the steeper slopes east of the wetland.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-7

Figure 11-3Option 1: Remove Solid Waste Material and Plant Wetland Marsh VegetationAmerican Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-8

The portions of the wetland selected for taro production would initially require the excavationof fill material to a minimum soil depth of about one to two feet. In terms of soil preparation,the production of talo toto i le vai (wetland taro) will require manual and/or mechanical tillingof the soil and the possible application of some limited nutrients to the soil.Taro cuttings from disease-free propagating material would be used to establish the taro. Thecuttings are part of a taro plant stem about 12 to 18 inches long that is attached to a 2 to 3-inchsection of the corm. Such cuttings would ideally be obtained from the Samoa Ministry ofAgriculture in Apia or the ASG Department of Agriculture. Before planting, selected tarocuttings should be carefully inspected, washed with potable water, soaked in a 10 percentbleach solution for 30 seconds, and stored in a dry, cool, and well-ventilated area for 3 to 5days before planting.Comparative Benefits and ImpactsPPC’s evaluation of the two alternate restoration and enhancement strategies is summarized inTable 11-2. Both options generate a comparable overall level of project benefits. However,slightly greater benefits are afforded by Option 1 (Figure 11-3).Option 1 desirably removes solid waste material from the wetland and likely restores thewetland to a coastal marsh through the planting of selected wetland plants. Theimplementation of Option 2 also would remove solid waste material as well as wetland plantsto permit some subsistence agricultural use.Despite their apparent project benefits, both options are moderately expensive to implement iflight of the extensive requirements associated with the removal and hauling of solid wastematerial. It also likely that both options may not be well received by local residents. Oneresident suggested to PPC in November 1999 that Fusi residents would likely appreciate theremoval of solid waste material. However, once this material would be removed, villageresidents would likely prefer to use the land for general residential land uses.TABLE 11-2COMPARATIVE EVALUATIONWETLAND RESTORATION AND ENHANCEMENT OPPORTUNITIESFUSI WETLANDOptionProjectCostResidentialLand UsesSubsistenceAgricultureFish &InvertebrateHabitatWetlandVegetationHabitatStormwaterDetentionFloodHazards &PropertyDamage1 MC LB NBC NBC SB NBC NBC2 MC LB SB NBC LC NBC NBCNotes: Potential project benefits were rated by PPC as follows:SB Significant project benefitsLC Limited undesirable consequencesMB Moderate project benefitsMC Moderate undesirable consequencesLB Limited project benefitsSC Significant undesirable project impactsNBC No anticipated project benefits orundesirable consequencesSource: Pedersen Planning Consultants, 2000American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-9

Recommended Option and Estimated Project CostShould reasonable village support exist for Option 1, this project is recommended for projectimplementation. While costly, this wetland enhancement project is attractive because theproject could likely achieve restoration of a disturbed marsh to a coastal marsh. Removal andhauling of solid wastes, as well as the planting of coastal marsh plants is estimated to costroughly $10,224 (Table 11-3 and Table 11-4).TABLE 11-3PRELIMINARY COST ESTIMATECOLLECTION, REMOVAL AND HAULING OF SOLID WASTE MATERIALFUSI WETLANDLABORPersonnel Number Hours Hourly Rate ($) Cost ($)Supervisor 1 80 15 1,200Heavy Equipment Operator 3 60 13 2,340Laborer 4 80 6 1,920All Personnel 8 580 $5,460MATERIALSItem Quantity Unit Cost ($) Cost ($)Picks 4 15 60Sledge Hammers 4 25 100Shovel 4 22 88Weed-eaters 4 300 1,200Machetes 4 20 80Garbage Bags 50 boxes 5 250Wheel Barrows 4 50 200All Materials $1,978TOTAL LABOR AND MATERIALS $7,438Notes: Preliminary estimate assumes use of existing equipment owned by the ASG Department of Public Works.Source: Pedersen Planning Consultants, 2000TABLE 11-4PRELIMINARY COST ESTIMATEPROPAGATION AND PLANTING OF COASTAL MARSH VEGETATIONFUSI WETLANDLABORPersonnel Number Hours Hourly Rate ($) Cost ($)ASCC Plant Nursery Technician 1 104 10 1,040ASCC Field Crew Leader 1 20 8 160ASCC Field Crew Members 2 20 6 240All Personnel 4 164 $1,440MATERIALSItem Quantity Unit Cost ($) Cost ($)Coastal Marsh Plants 125 3 375Garbage Bags 20 boxes 5 100All Materials $475EQUIPMENTShovels 3 22 66Machetes 3 20 60Picks 3 15 45Wheel Barrows 2 50 100Weed-eaters 2 300 600All Equipment $871TOTAL LABOR AND MATERIALS $2,786Notes: Preliminary estimate assumes use of existing equipment owned by the ASG Department of Public Works.Source: Pedersen Planning Consultants, 2000American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-10

Long-Term Monitoring and Site Maintenance RequirementsLong-term resource management activities associated with the enhancement and restoration ofthe Fusi wetland should include the seasonal monitoring of selected resource characteristics andperiodic site maintenance.Resource MonitoringThe process of resource monitoring will involve completion of the following steps by ASEPA,ASCMP, or other ASG agency staff:• Prepare a field map of restoration and enhancement site from available digital files inthe American Samoa GIS.• Go to the restoration and enhancement site and collect information summarized on fieldmonitoring worksheet.• Upon return to office from the field, incorporate new spatial data, topographic features,and resource conditions within the American Samoa GIS as points, lines, or polygons.• When desired, expand attribute tables for points, lines and polygons to enhance thedescription of resource characteristics and changes.• Make an annual evaluation of selected resource conditions that analyzes theeffectiveness of the overall restoration and enhancement project.Long term monitoring of the Fusi wetland restoration and enhancement project will requireperiodic examinations of, at least, the following:• the presence of surface or groundwater flow;• survival of planted, wetland vegetation;• changes in land uses immediately adjacent to the wetland; and,• point-source discharges, e.g., wastewater from piggeries.The types of information needed, monitoring frequency, monitoring locations, and evaluationparameters are summarized in Table 11-5. A field work sheet or checklist, which can be usedin the field, is provided in Table 11-6.Future resource monitoring can be effectively performed through bi-annual site visits to theFusi wetland. This approach will enable comparisons during wet (December through March)and dry (April through November) seasons of the year. Additional visits should also take placeduring and/or following significant stormwater events that may be generated from periods ofsignificant rainfall.The availability of the American Samoa geographical information system enables theincorporation of most all resource monitoring information within the GIS. Field data can besummarized in attribute tables or databases. Digital photos can be linked to digital maps of therestoration site.Vehicular and pedestrian access to the wetland is largely dependent upon the cooperation andauthorization of local residents in Fusi. If access is granted, the entire wetland should bemonitored via walk-through surveys.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-11

TABLE 11-6FIELD MONITORING WORKSHEETAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANFUSI WETLANDDate(s) of field monitoring:_______________Agency/Company Represented:Name(s) of observer(s):Fusi Wetland(Circle "yes" or "no".)STREAM AND WETLAND HYDROLOGY1 Is there evidence of a fresh water spring discharge? Yes No2 Are surface flows entering the wetland? Yes NoSURVIVAL OF NEW WETLAND PLANTS3 Count number of surviving new coastal marsh plants.CHANGES IN LAND USE4 a Document type and number of new land uses within 100 feet of the wetland perimeter.Number of facilities:Briefly describe each new facility:ResidentialCommercialIndustrialPublic FacilityCommunity FacilityAgriculturalb Map location of new land uses on field map. ___ Check, when field map is so marked5 a Do any existing land uses, within 100 feet of the wetland perimeter, appear to havesustained damage from past or recent stormwater events? Yes Nob If so, where? (Locate on field map.) ___ Check, when field map is so markedNON-POINT DISCHARGES INTO WETLAND6 Type of discharges: Briefly describe type of discharge:PiggeryStormwaterCesspoolIndustrialCommercial7 Locate discharge on field map ___ Check, when field map is so marked

TABLE 11-5LONG-TERM RESOURCE MONITORING REQUIREMENTSAMERICAN SAMOA WETLAND RESTORATION AND ENHANCEMENT PLANFUSI WETLANDResource Information Monitoring Monitoring Monitoring EvaluationRequirement Frequency Method Location(s) ParametersWetland/Stream Surface or 1 x (Dec-March) Visual observation Along north and east margin of wetland Presence of flow from spring or surface runoff from uplandHydrology groundwater flow 1 x (April-Nov) slopesWater Quality Changes in land 1 x (Dec-March) Take digital photos, document type and Within 100 feet of wetland perimeter Do new land uses generate non-point surface or subsurfaceuses 1 x (April-Nov) estimated size, locate changes on field discharges into the wetland?mapVegetation Survival of new 1 x (Dec-March) Take visual count of new coastal marsh Within entire wetland Number of plants that remaincoastal marsh 1 x (April-Nov) plantsplants

Any future monitoring stations or sites that may be established should be used consistentlyunless unanticipated events, new land uses, or access issues prevent continued use. Whennecessary, changes in the location of monitoring stations should be documented and spatiallylocated within the American Samoa GIS. PPC has provided digital files for the Wetland andStream Restoration and Enhancement Plan that provide a departure point for locating futureresource monitoring stations within the wetland.All photographs should be incorporated into the digital photo album developed by PPC inconjunction with the Wetland/Stream Restoration and Enhancement Plan. This will enable along-term comparison of resource information.Site MaintenancePeriodic site maintenance should take place within the Fusi wetland two times per year. It isrecommended that maintenance take place immediately following the resource monitoringactivities to reduce the amount of air travel to the site. However, local residents could likely behired to accomplish long-term site maintenance to eliminate the need to transport amaintenance crew from Tutuila.The collection of solid wastes within the wetland is expected to represent the primary focus oflong-term site maintenance. A crew of two persons will be necessary to walk through the Fusiwetland for periodic, long-term maintenance. The use of garbage bags and machetes will beneeded to support these activities.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Fusi Wetland, Page 11-14

Chapter TwelveFUTURE PROGRAM MANAGEMENTRECOMMENDED PROGRAM PARTICIPANTSImplementation of the recommended restoration and enhancement projects will require adiverse set of experience and expertise that is available from, at least, the followinggovernmental agencies in American Samoa:• American Samoa Environmental Protection Agency• American Samoa Coastal Management Program• American Samoa Community College, Land Grant Program• ASG Department of Marine and Wildlife Resources• American Samoa Power Authority• ASG Department of Public Works• U.S. Natural Resources Conservation ServiceIt is essential that restoration and enhancement projects be carried out on a cooperative basis bythese agencies. A representative of either the American Samoa Environmental ProtectionAgency or the American Samoa Coastal Management Program should assume the role ofoverall program manager to organize and administer the overall cooperative program.Representatives of the other participating agencies could meet periodically, e.g., monthly, withthe overall program manager to prioritize restoration and enhancement projects, coordinate andschedule specific project tasks, keep abreast of project status, share information gained fromfield observations and other related information. In order to reduce some duplication, anexisting inter-agency committee organized by ASEPA for future watershed management couldserve as this group.Another option is to use the proposed Watershed Resource Management Board that wasrecommended in the recent Watershed Protection Plan. Stream and wetland restoration andenhancement projects could clearly represent a portion of the proposed mandate of the WaterResource Management Board. The Board could again be comprised of the members on theexisting inter-agency committee for watershed management.INDIVIDUAL PROJECT ASSIGNMENTSEach restoration and enhancement project will require one or more individuals to manage andcarry out specific restoration and enhancement projects at each of the selected wetlands andstreams. Project managers for each project would logically report to the overall programmanager. Recommended village coordinators and stream team personnel would report toproject managers. In some cases, e.g., Alao wetland, only a project manager would be requiredgiven the recommended scope of enhancement projects.A general description of the duties and responsibilities associated with each of the individualproject assignments is presented in the following paragraphs.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Future Program Management, Page 12-1

Project ManagerRepresentatives of any of the participating agencies would logically serve as individual projectmanagers. For example, if the primary thrust of a project is to enhance aquatic fish andinvertebrate habitat, the selection of a project manager from the ASG Department of Marineand Wildlife Resources would be ideal if qualified personnel were available to assume thisresponsibility.The project manager would direct the activities of a village project coordinator andrecommended Stream Team, coordinate with traditional village leaders and residents livingadjacent to the selected stream or wetland, and coordinate with representatives of other ASGagencies.Village CoordinatorThe approval and commitment of local villages to each enhancement and restoration project isessential. The commitment of a local village coordinators to this responsibility will, in largepart, depend upon their understanding of resource relationships and potential streamenhancement benefits.A village coordinator, e.g., pulenuu or matai, would be assigned to each project to:• organize and mobilize Stream Team cleanup and long-term stream maintenance activities;• observe and document stream and wetland conditions during and following future stormevents;• monitor the conditions of other resources, e.g., vegetation, fish and invertebrates; and,• keep the overall project manager abreast of work progress.Stream and Wetland TeamsAmerican Samoans are well known for their excellent ability to work collectively in groups.The use of small Stream or Wetland Teams can capitalize upon these capabilities.Where recommended, stream and wetland Teams of various sizes should be organized andemployed by ASEPA or ASCMP to initially clean up selected stream channels and wetlands, aswell as provide long-term monthly maintenance. These teams should only be establishedwhere stream or wetland cleanups are necessary to initiate other restoration and enhancementprojects. It is envisioned that their work would, in some cases, be supplemented by heavyequipment support from the American Samoa Power Authority or the ASG Department ofPublic Works.Stream and wetland teams would ideally be comprised of members of the village aumaga, orother village residents. Each team member could be supplied with attractive T-shirts, caps,pants, and/or boots that identify that they are part of a specific stream team, e.g., Papa StreamTeam. The use of some type of informal uniform should be considered to bring about somecamaraderie among these employees. Uniforms for these personnel would also help advertisethe project to local residents as these employees work in local streams and wetlands.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Future Program Management, Page 12-2

SELECTED AGENCY ASSIGNMENTSAside from the coordination of overall program coordination, it is recommended that someagencies provide specific technical assistance in the field. The field activities envisioned forthe ASCC Land Grant Program and ASG Department of Marine and Wildlife Resources arepresented in the following paragraphs.ASCC Land Grant ProgramIt is envisioned that the ASCC Land Grant Program would provide riparian tree seedlings tohouseholds along selected streams or adjacent to selected wetlands. Land Grant has experiencewith this task through its ongoing Forestry Stewardship Program.Land Grant representatives would also provide local residents with some technical assistanceconcerning desired planting methods, as well as perform all in-stream plantings. However,local residents can perform plantings along higher stream banks and riparian areas effectively.American Samoa Department of Marine and Wildlife ResourcesOne or more biologists from the American Samoa Department of Marine and WildlifeResources could be used to perform an initial monitoring program of fish and invertebrates.Long-term monitoring of aquatic fish and invertebrates may be able to be accomplished by theASDMWR biologists, village coordinators, other village resident, if some initial basic trainingis provided by an ASDMWR representative, or a consultant.POTENTIAL PARTICIPATION FROM OTHER COMMUNITY ORGANIZATIONSDespite the potential availability of federal funds for this project, ASEPA and ASDOC shouldencourage the participation of one or more community organizations, e.g., Rotary Club, thatregularly support community improvement projects. General solicitations should also be madeto private businesses and possible individual donors in the community. Communityorganizations and local businesses may desire to provide some financial support and/ormaterials needed by the project.These potential contributions are important because they can express a greater communitycommitment to the stream enhancement project. They may also stir greater interest amongvillage residents. If and when contributions are obtained, ASEPA and ASDOC should clearlyhonor their commitment to the project in the form of some public recognition of theirparticipation.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, Future Program Management, Page 12-3

REFERENCESBiosystems Analysis, Inc. January, 1992. A Comprehensive Wetlands Management Planfor the Islands of Tutuila and Aunu’u, American Samoa. American SamoaEconomic Development Planning Office and Coastal Management Program. PagoPago, American Samoa.Biosystems Analysis, Inc. September, 1993. A Comprehensive Wetlands ManagementPlan for the Islands of Manu’a, American Samoa. American Samoa EconomicDevelopment Planning Office and Coastal Management Program. Pago Pago,American Samoa.Bledsoe, Brian P.; Wuenscher, James E.; and Sutter, Lori A. 1998. Using GeographicInformation Systems to Identify and Prioritize Potential Wetland Restoration Sitesin Coastal North Carolina. North Carolina Division of Coastal Management.California Resources Agency. 1998. California Wetlands Information System:Explanation of Tracking Table Categories.DuPoldt, Jr., Carl A.; Terrell, Charles R.; Franzen, Robert W.; and Wengrzynek, Robert J., Jr.1991. Nutrient and Sediment Control System, Environmental Quality TechnicalNote No. N4. U.S. Department of Agriculture, Soil Conservation Service.Engbring, John, and Ramsey, Fred L. 1989. A 1986 Survey of the Forest Birds of AmericanSamoa. U. S. Department of Interior, Fish and Wildlife Service and American SamoaOffice of Marine and Wildlife Resources. Pago Pago, American Samoa.Louisiana Department of Natural Resources, Coastal Restoration Division. 1998. VegetationPlanting Program. Louisiana Department of Natural Resources.Madrigal, Larry G. Field Guide of Shallow Water Marine Invertebrates of AmericanSamoa. American Samoa Government Department of Education, Division ofCurriculum and Instruction. Pago Pago, American Samoa.Pedersen Planning Consultants. 2000. American Samoa Watershed Protection Plan,Volumes 1-4. American Samoa Government Environmental Protection Agency andCoastal Management Program. Pago Pago, American Samoa.Pedersen Planning Consultants, 2000. Tualauta County Land Use Plan – Draft. AmericanSamoa Department of Commerce. Pago Pago, American Samoa.Stemmermann, Lani. 1981. A Guide to Pacific Wetland Plants. U. S. Army Corps ofEngineers, Honolulu District. Honolulu, Hawaii.The World Conservation Union. Wetlands and Coastal Zones. IUCN Regional Office forMesoamerica.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, References-1

U. S. Army Corps of Engineers. July, 1981. American Samoa Stream Inventory, Island ofTutuila, American Samoa Water Resources Study. U. S. Army Corps of Engineers,Honolulu District. Honolulu, Hawaii.U.S. Federal Interagency Stream Restoration Working Group. 1998. Stream CorridorRestoration Principles, Processes, and Practices. National Technical InformationService.U.S. National Resources Conservation Service, Hawaii State Technical Committee. 1998.Interim Hawaii Procedure for Determinations of Wetland Minimal Effect.Wass, Richard. November, 1998. Personal Communication. Manager, Hakalau WildlifeRefuge, Island of Hawaii. U.S. Fish and Wildlife Service. Hilo, Hawaii.Wetland Science Institute. 1998. Wetland National Practice Standards: WetlandRestoration, Wetland Enhancement, Wetland Creation, Constructed Wetland, andShallow Water Management for Wildlife. U.S. Natural Resources ConservationService.Whistler, Dr. W. Arthur. 1996. Samoan Herbal Medicine (‘O La’au ma Vai Fofo oSamoa). Isle Botanica. Honolulu, Hawaii.Whistler, Dr. W. Arthur. Wayside Plants of the Islands. (A Guide to the Lowland Flora ofthe Pacific Islands including Hawaii, Samoa, Tonga, Tahiti, Fiji, Guam, Belau).Isle Botanica. Honolulu, Hawaii.American Samoa Wetland/Stream Restoration and Enhancement PlanFebruary 2001, References-2

APPENDIX ASUMMARY OFPLANTSOBSERVED BYPEDERSEN PLANNING CONSULTANTSNOVEMBER 1999

APPENDIX APLANTS OBSERVED BY PEDERSEN PLANNING CONSULTANTSNOVEMBER 1999Species Family EnglishNameSamoan NameWetlandStatusAcmella uliginosa Asteraceae -- -- NLAcrostichum aureum* Pteridaceae swamp fern -- OBLAlocasia macrorrhiza @ Araceae giant taro ta’amu FACAlternanthera sessilis Amaranthaceae sessile joyweed -- FACAntidesma sphaerocarpum* Euphorbiaceae -- -- NLAsplenium nidus* Aspleniaceae bird’s-nest fern laugapapa (Epi.)Axonopus compressus Poaceae carpet grass -- FACBambusa vulgaris Poaceae bamboo ‘ofe palagi NLBarringtonia samoensis* Barringtoniaceae -- falaga FACWBidens alba Asteraceae beggar’s-tick -- NLBischofia javanica* Euphorbiaceae -- ‘o’a NLBlechum pyramidatum Acanthaceae -- -- FACBrachiaria mutica Poaceae California grass -- FACWBruguiera gymnorrhiza* Rhizophoraceae oriental mangrove togo tane FACCalophyllum inophyllum* Clusiaceae Alexandrian laurel fetau NLCananga odorata @ Annonaceae ilangilang moso’oi NLCanna indica Cannaceae Indian shot fanamanu FACUChamaesyce hypericifolia Euphorbiaceae graceful spurge -- FACUCeiba pentandra Bombacaceae kapok vavae NLClerodendrum chinense Verbenaceae Honolulu rose losa Honolulu FACCocos nucifera* Arecaceae coconut niu FACUCostus speciosus Zingiberaceae Malay ginger -- NLCoix lacryma-jobi @ Poaceae Job’s tears sanasana FACWColocasia esculenta @ Araceae taro talo OBLCommelina diffusa @ Commelinaceae commelina mau’utoga FACCyclosorus interruptus* Thelypteridaceae marsh fern vao tuaniu OBLCyperus alternifolius Cyperaceae umbrella sedge -- FACWDavallia epiphylla* Davalliaceae -- laugasese (Epi.)Davallia solida* Davalliaceae leather fern laugasese (Epi.)Desmodium triflorum Fabaceae beggarweed -- FACUDigitaria setigera* Poaceae -- -- FACDiospyros samoensis* Ebenaceae Samoan ebony ‘au’auli NLDissotis rotundifolia Melastomaceae dissotis -- NLDysoxylum samoense* Meliaceae -- maota mamala NLEleocharis dulcis* Cyperaceae water chestnut ‘utu’utu OBLEriochloa procera Poaceae tropical cupgrass -- FACErythrina fusca* Fabaceae -- lalapa?, gatae OBLErythrina subumbrans Fabaceae Dadap gatae palagi OBLErythrina variegata* Fabaceae coral tree gatae NLFicus benghalensis Moraceae Indian banyan* pulu NLFicus tinctoria* Moraceae dyer’s fig mati FACFimbristylis autumnalis Cyperaceae -- -- NLFimbristylis cymosa* Cyperaceae -- -- FAC+Flueggea flexuosa Euphorbiaceae -- poumuli NLGeniostoma rupestre* Loganiaceae -- lau mafatifati NLHernandia nymphaeifolia* Hernandiaceae Chinese lantern tree pu’a NL

Species Family EnglishNameSamoanNameWetlandStatusHibiscus abelmoschus @ Malvaceae -- -- NLHibiscus manihot Malvaceae tree spinach pele NLHibiscus tiliaceus* Malvaceae beach hibiscus fau FACWHoya australis* Asclepiadaceae wax flower lau mafiafia (Epi.)Inocarpus fagifer @ Fabaceae Tahitian chestnut ifi FACUIpomoea pes-caprae* Convolvulaceae beach morning-glory -- FACKyllinga brevifolia @ Cyperaceae -- -- FACKyllinga nemoralis Cyperaceae -- -- FACKleinhovia hospita* Sterculiaceae -- fu’afu’a NLLeucaena leucocephala Fabaceae wild tamarind -- NLLudwigia hyssopifolia Onagraceae -- -- FACWLudwigia octovalvis Onagraceae willow primrose -- OBLLuffa cyclindrica* Cucurbitaceae -- -- NLMacaranga harveyana* Euphorbiaceae -- lau pata NLMangifera indica Anacardiaceae mango mago FACUManihot esculenta Euphorbiaceae cassava manioka NLMariscus javanicus* Cyperaceae -- selesele FACWMerremia peltata* Convolvulaceae -- fue lautetele NLMerremia umbellate Convolvulaceae -- -- NLMikania micrantha Asteraceae mile-a-minute vine fue saina NLMomordica charantia Cucurbitaceae balsam pear -- FACMorinda citrifolia @ Rubiaceae Indian mulberry nonu NLMusa Xparadisica @ Musaceae banana fa’I FACUNeonauclea forsteri* Rubiaceae -- afa FACUNephrolepis hirsutula* Nephrolepidaceae sword fern vao tuaniu NLOperculina turpethum* Convolvulaceae -- -- NLOphioglossum reticulatum* Ophioglossaceae adder’s tongue fern -- NLOplismenus compositus @ Poaceae basket grass sefa? FACPandanus tectorius* Pandanaceae screwpine laufala FACUPaspalum conjugatum Poaceae T-grass vao lima FAC+Paspalum vaginatum Poaceae salt grass -- FACWPassiflora foetida Passifloraceae love-in-a-mist pasio vao FACUPennisetum purpureum Poaceae elephant grass -- FACUPhymatosorus scolopendria* Polypodiaceae -- lau magamaga (Epi.)Pyrrosia lanceolata* Polypodiaceae -- lau tasi (Epi.)Pycreus polystachyos Cyperaceae -- -- FACRhizophora mangle* Rhizophoraceae red mangrove togo fafine OBLRhynchospora corymbosa* Cyperaceae -- selesele OBLSenna alata Fabaceae candelabra plant la’au fai lafa FACUSorghum sudanense Poaceae -- -- NLSpondias dulcis @ Anacardiaceae Polynesiam plum vi NLStachytarpheta urticifolia Verbenaceae blue rat’s-tail fuapepe FACStictocardia tiliifolia Convolvulaceae -- palulu FACUStruchium sparganophorum Asteraceae -- -- FACWThespesia populnea* Malvaceae Pacific rosewood milo FACVigna marina* Fabaceae beach pea fue sina FACUWedelia trilobata Asteraceae -- -- FACU(epi.)=epiphyte. FACU-facultative upland plant. FAC=facultative plant. FACW-facultative wetland plant.NL=not listed. OBL-obligate wetland plant. Native species are indicated by an asterisk (*). Polynesian introductionsare indicated by a @ .

APPENDIX BSUMMARY OFAQUATIC MACROFAUNAL ORGANISMSOBSERVED BYPEDERSEN PLANNING CONSULTANTSNOVEMBER 1999

APPENDIX CSUMMARY OFAQUATIC MACROFAUNAL ORGANISMSOBSERVED BYU. S. ARMY CORPS OF ENGINEERS,U.S. FISH AND WILDLIFE SERVICE,AND B. P. BISHOP MUSEUMAT SELECTED SITESJULY 1981

american samoa - University of Hawaii at Manoa Botany Department

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