NamdrikAtollRapidCoastalHazardAssessment1.Introduction1.1BackgroundInrecentyearstheMarshallIslandsnationalconservationandbiodiversitystrategy(theReimaanlok)hasbroadened the scopeofwork to incorporateclimatechangeandcoastalmanagementactivities.Asaresult,Reimaanlok fieldvisits currentlyhaveanadded focusplacedonassessing coastalhazardsandpotential adaptation strategies. The following assessment is a component of the larger communitydrivenresourcemanagementplancurrentlyinprogressforNamdrikAtoll.TheassessmentispartoftheReimaanlokprocessandisintendedtoprovideasynthesisofinformationonhazardswithinthecoastalzone.Thepurposeoftheassessment istousethecommunitydrivenReimaanlokprocessalongwithabrief field investigation to isolate key coastal hazards to aid in the implementation of adaptationstrategies.Tip:ThisisagenericintroductiontotheReimaanlokandthepurposeofintegratingclimateactivitiesintothedevelopmentofthemanagementplan.Thissectionwillbelargelythesamebetweenislands.1.2NamdrikAtollAtoll islandsare lowlyingaccumulationsofsedimentperchedatopacoralreefcomposedofmaterialproduced on the surrounding reef. These islands are widely considered to be some of the mostvulnerablelandformsonearthwithregardstotheimpactsofclimatechange.Atollislandstypicallyhavehighlydynamicshorelines,witherosionandaccretionconstantlyreshapingislands.Bothclimatechangeand locally induced stressors are acknowledged as drivers of coastal change and hazards alongpopulatedatollcoastlines.NamdrikAtoll (lat/long) is located (240miles)west southwestofMajuro,within theMarshall IslandsRalik chain of islands (Fig X). As part of the National Conservation and Biodiversity Strategy (theReimaanlok) a rapid coastal hazard assessmentwas undertaken during (date) in order to assess thecurrentstatusoftheNamdrikcoastalzonewhileaddressingissuesraisedbythelocalcommunity.

FigureX.NamdrikAtoll(53645N,1680645E)islocated240mileswestsouthwestofMajuroAtoll.Tip: This is a generic introduction to the atoll in question and the dates of the assessment. Includeinformationon lat/long,youmightwant to includedistanceandbearing fromMajuro (as thatswhatmostpeoplearefamiliarwith)i.e.Namdrikis240mileswestsouthwestofMajuroatoll.1.3PhysicalSettingNamdrikatollisamidoceanatoll,withalagoonapproximatelyXkm2,withXkm2ofislandsandXkm2ofreefflat.Itconsistsoftwoislands(nameandMadmad).Madmad,locatedinthenorthwestcornerofthe atoll isuninhabited and contains large standsofmangrove swamp.NAME is a continuous islandtypicallyXmwide.InthesouthwestsectionoftheatollNAMEiswider(uptoXm)andishometobothafreshwaterlensandthemajorityofthepopulation.Tip:Thissectionshoulddescribetheatoll.Theshape,size,keyislandsetc.Ifatollshavepasses,mentionthenamesand locationsof thepasses.Offshore reefsandanyother keyphysical features shouldbe

mentioned.Including,butnotlimitedtoswamps,mangroves,areasofhighdunes,reefdepositsofsand,significantpatchreefsetc.SatImage

FigureXSatelliteimageofNamdrikAtoll.

Tip:Asatellite imageofeachatollshouldbeacquiredbeforeANYReimaanlokvisitsareundertaken. IftheyarenotpublicallyavailablethroughtheRMIEPA,trySOPACorintheeventnoimageryisavailablefundsshouldbeallocated toobtain recent imagery .High resolutionsatellite imagery isveryuseful inmappingthekeycoastal featuresandwhendigitizedwithinGISpackagesprovidea lotof informationthatcannoteasilybecollectedinthefield.Somesources:RMIEPA,SOPAC,www.digitalglobe.com

Figure X Key physical zones and assets of Namdrik Atoll. Namdrik is notable for the relatively small lagoon and the absence of any passages connecting the lagoon to the open ocean. The population is largely clustered in the southwest section of the island, with the majority of assets/infrastructure on the lagoon side of the island. Tip:Beforeanyvisit isevenundertakenbaselinemaps shouldbeproduced throughdigitizing satelliteimagery.Bothnaturalandmanmade features shouldbedigitizedand storedas shapefiles.Additionalinformationcollectedinthefieldshouldbeaddedtothesemaps.1.4TidalRegimeAtpresent thereareno tidalpredictions issued forNamdrikAtoll.During theassessment itwasnotpossibletoaccuratelydeterminefeaturesofthetidalregimeincludingMSL,meanhighwaterorspringtidelevel.Tip:Tidalinformationisavailableformany,butnotallRMIatolls.PredictionsareproducedbyNOAAandthe Australian Bureau of Meteorology (BOM). http://tidesandcurrents.noaa.gov/ andhttp://www.bom.gov.au/oceanography/tides/ are two valuable websites with tidal information.

!!

!

!!!

!

!!!!

!!

! ! !

!!!

!!

! !

!!!!! !

!!!

!!!

!

!

!

!

!

!!!!!!!!!

!!!

!!!!

!!!!!!! !!!

!!!!

!!!!!! !!!!

!!!

!!!

! ! ! !!

!

!

!

!

!

!

!

!

!

!

!

!

!

!

!!

!

!!

!!!

!!!

!

!

!

!

!

!

!

!!

LegendDeep lagoon

Shallow lagoon

Vegetation

Reef flat

Airport! Buildings

0 500 1,000 Meters

Kwajalein(NOAA)andMajuro(BOM)havetidegauges,otheratollsarecorrectionsbasedoffKwajaleinandMajuro.1.5FetchNamdrik lagoon is small relative to other atolls in the Marshall Islands. Land encircles 64% of thelagoon.Asa result, lagoon shorelinesare largely fetch limited.Whileoceanicwavesareable topassovertheexposedreefflatandintothelagoonduringperiodofhighwater(hightide),thesewavesarelargely filteredby the reef flat.FetchwithinNamdrik lagoon isamaximumof~5km andalongmoststretchesofshoreline isbetween34km.Waveswithin the lagoonare for the largepart fetch limiteddue to the deep lagoon >30m in most places. However, in areas of shallow lagoon depth inducedbreakingofwaveswouldoccur,resultinginsmallerwavesreachingtheshoreline.Modelingwavesinthenearshore is complex and largely beyond the scope of this assessment. For the purposes of thisassessment a simple maximum lagoon wave height is calculated using US Army Core of Engineersformulausinganonlineapplet1.Thelagoonisconsideredauniformlydeepbasinofwater30mdeepandawindspeedof12ms1wasused.Thisisconsideredupperlimitsoflikelynonstormwindspeed.The limited fetch along the lagoon shoreline limitswaves to approximately 54 cm. Thiswas verifiedduring community consultations, where the local Mayor (insert name) indicated that waves rarelyexceedshin/kneeheight.Basedonthemaximumwaveheightwavecalculationandobservationsmadebycommunitymembers it isunlikely that locallygeneratedwaveswouldexceed50cm,exceptunderrarecircumstances.However,evenwavesofthissizeareabletomobilizebeachsediment,driveerosionandincreaselocalizedfloodingwhencoincidingwithhightide.Tip:Windstrengthandduration,combinedwithwaterdepthandfetcharethekeycharacteristicswhichdeterminewaveheight.Oceanshorelinesaresubjects toboth locallygeneratedwindwavesandswellwaves which can be produced many thousands of miles offshore. To get an understanding of themaximum conditionswithin the lagoonwemustmeasure the fetch (from satellite imageryusingGISsoftware)andcomeupwithvaluesfor lagoondepthandwindstrength.ItisrareintheRMIforlagoondepthtobeknown,butassume30mdepthinareaswheretheseafloorisnotsurveyedorvisiblefromthesurface.Wind speed varies a lot and in the absence of anymeteorological data onemustmake an

1http://woodshole.er.usgs.gov/staffpages/csherwood/sedx_equations/RunSPMWave.html

assumption. ForNamdrik 12ms1was used, this equates to 27mph.Wave information can also beextractedfromcommunityconsultations,forNamdriktalkingto localresidentsabouthow largewavesgotonthebeachadjacenttotheirpropertyverifiedthenumericalcalculations.1.6MarshallIslandsTyphoonHazardsTAKENFROMSPENNEMANN2In theMarshall Islands there is a common belief that the southern atolls do not experience serioustyphoons, and that Majuro Atoll is relatively "safe." The previous examples of the 1905 and 1918typhoonsor the1979 floodingareseenbymany in theRMIas"freak"exceptions,rather thanas thestandard level of threat. The question arises whether this is indeed so. In a review of 40 years oftyphoondata,BirdwellandDaniels(1991)showedthatprobabilityofatropicalstormcenteroccurringper year in the 5x5 degree areas in which the Marshall Islands are located is 28.75%, while theprobabilityofatyphoon/hurricaneis10%.Butthereisevidencethatthesetyphoonsareclustered.

An analysis of the historic record of typhoons in the Marshall Islands has identified a significantassociationbetween theoccurrenceofENSOand theoccurrenceof typhoons in theMarshall Islands(SpennemannandMarschner,1994).Whilsttyphoonsnormallyoccurfurthertothewest,thewarmingoftheoceanwatersaroundtheMarshall Islands,aspartoftheENSOphenomenon,spawnstyphoonsfurthertotheeast.Theresultsofthestatisticalanalysissuggestthattyphoonsare2.6timesmorelikelytooccurduringENSOyears,witha71%chanceofatyphoonorseveretropicalstormstrikingduringanENSOyear,andonlya26%chanceofonehappeningduringanonENSOyear.TheobservedassociationbetweenENSOandthehistoricoccurrenceoftyphoons(SpennemannandMarschner1994,inpress)fitswell within the expectation of the assumption of typhoon genesis and seasurface temperaturedevelopmentsduringENSOphenomena.Further, theobserved ratioof2.6 timeshigher likelihoodoftyphoonsduringENSOyearsfitswellthefrequencypostulatedbyWendland(1977).

Tip:ThissectionisliftedstraightoutofSpennemannandisgoodintroductiontotyphoonsintheMarshallIslands.

1.6.1NamdrikStorms

2http://marshall.csu.edu.au/Marshalls/html/typhoon/typhoon.html

Consultationswith theNamdrik community revealed significantdamage tohousing (estimatedup to90%destroyed)asaresultofatyphoonin1979.Reefflatdepositsoflargecoralboulderssuggestthatlargestormseventshaveoccurredinthepast.

Figure X. Large coral boulders deposited on the western reef flat of Namdrik Atoll indicate high wave energy events associated with typhoons in the past. Coral boulders have been colonized by vegetation suggesting the boulders are stable and have been in place for some time. Local myths are used to explain the deposition of the boulders. 1.7WaveclimateLimited information is available on the oceanic wave climate surrounding Namdrik Atoll. Given theregionalwaveconditions it is likelytobedominatedbynortheasterlytradewindsbetweenDecemberandMayandmoresettled,sometimevariablewindsduringtheremainderoftheyear.Occasionallocalordistantstormscangeneratesignificantswellevents.Tips:Withtime,theMajurowavebuoywillprovideawaveclimatefortheMarshallIslands.Therearelikely regionaldifferences throughout theMarshall Islands.However, thisbuoywillprovide theonlyaccuratelongtermmeasureofwaveconditions.http://cdip.ucsd.edu1.8IslandMorphology

FiguresXandXpresentcrosssectionprofileofNamdrikAtoll(seeFigureXforlocation).Theoceansidecoast is typically characterizedby abeach composedofmediumsized sandwith surfacedepositsofcoralgravel.Thebermofvaryingheightispresentalongtheoceanshoreline,withamaximumheight23m above highwatermark, particularly in the area around the Coprawarehouse at (lat/long). Theoceansideberm istypicallycomposedofamixofsandandgravel.Landwardofthebermtheterrainslopes relativelyevenly towards to the lagoon shoreline. Inplaces,Taropitsandareasof swamparepresent towards the lagoon coast. There is little evidence of berm development along the lagoonshoreline,inplaceswhereonewasmeasureditwastypically

Figure X Cross-section profile through NAME island, Namdrik. Profile extends from lagoon through the island to the ocean coast. Tips:Crosssectionswerederivedfromdumpylevelsurveys(seesurveyingguide).AtNamdriktherearenotidalpredictionssoitisdifficulttoreferencetheprofilestoMeanSeaLevel(MSL).ProfilelinescollectedonatollswithtidalpredictionsshouldbepresentedrelativetoMSL.ThesurveyingguideprovidesinformationonhowtoundertakesurveysandhowtoprocesstheinformationpresentingitrelativetoMSL.Keyfeaturesshouldbenotedontheprofilesuchasbuildings,crops,roadsetc.2.ClimateChangeintheRMI2.1SealevelriseSealevelriseiswidelyconsideredtobethesinglegreatestclimaticthreattolowlyingatollnations.Sealevelriseisdrivenbythemeltingoficestoredinglaciersandterrestrialicecapsalongwiththeexpansionofoceanwaterastemperaturesrise.Sealevelriseisneitheruniformacrossspaceorthroughtime.WithintheMarshallIslandsgreatvariationsinsealevelareobservedparticularlyduringperiodsofElNino.2.2PastAcrosstimescalesofhours,weeks,yearsandcenturiesglobalandlocalsealevelisconstantlychanging.Someoftheseshorttermchangesinsealevelarearesultoftidesormeteorologicalevents.Longtermsealevelvariabilityisdrivenbychangesinglobaltemperatures.Itisonlyoverthepast100years(andmorerecentlyintheRMI)thatequipmenthasbeenusedtomeasurechangesinsealevel.Withinthe

0 20 40 60 80 100 120

0.4

0.8

1.2

1.6

2.0

2.4

High tide level (6/2/2010)

Ocean side

Lagoon

Toe of beach Toe of beach

Elevation(m

eters)

Distance (meters)

RMIgaugeshavebeeninstalledinEnewetak(19511979),Kwajalein(1946present)andMajuro(1968present)

Figure X Majuro sea-level record (1968-present)

Tips:ThischartisbasedofftheMajurotidegaugeranbyBOM.FormostsouthernatollsthisisthemostappropriatesourceofhistoricSLinformation.ForatollsclosertoKwajaleinthereisSLdataavailablefromtheNOAAtidegaugeatKwajalein.Bothdatasets(usemonthly)areavailablethroughtheUniversityofHawaiiSeaLevelCenter.http://ilikai.soest.hawaii.edu/uhslc/2.3FutureAtpresent,thereisconsiderablediscussionanddebatesurroundingthemagnitudeandtimingoffuturesealevelrise.Whatiswidelyagreeduponisthatsealevelwillcontinuetoriseandthataccelerationintherateistobeexpected.TheIntergovernmentalPanelonClimateChange(IPCC)issuespredictionsforavarietyofSLRscenarios.Thisisbaseduponacomplexreviewofexistingscientificinformationandmodels.The2007assessmentissuedpredictionsofSLRbetween0.18mand0.59mbytheendofthecentury.Recentscientificresearchundertakenafterthe2007assessmentaddressedsomeoftheshortcomingsintheIPCCmethod(lackofconsiderationofthecontributionofcalvingoficetoSLR)indicatesthatSLRbytheendofthecenturycouldbeupwardsof1m.DespiteshortcomingsandrecentadvancesofinthepredictionofSLRthisassessmentadoptstheupperboundsoftheSLRpredictionsofferedbytheIPCC(0.59m)

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

70 72 73 75 77 79 81 83 85 87 89 91 93 95 97 99 01 03 05 07 09

Mon

thly

seale

vel

Year

Tips:ThereisagreatdealofinformationonSLRavailable.ReimaanlokteamsneedastandardmessageonSLR.TheIPCCisthemostrobustassessmentofSLR.However,someconsideritrelativelyconservativeandslowmoving,takingsometimetoadoptnewscientifictheoriesandpredictions.TheIPCCprojectionsshouldbeusedinReimaanlokassessmentswithmentionofthepossibilityofacceleratedratesofSLR.Arecent review undertaken by Chip Fletcher of the University of Hawaii is provided at:http://www.soest.hawaii.edu/coasts/publications/fletcher2009_sealevelreview.pdf2.4ClimateChangeandStorminessintheMarshallIslands3.ManandCoast3.1HumanModificationsWhilerelativelypristinecomparedtotheurbanatollswithintheMarshallIslands,Namdrikdoesexhibitevidenceofhumanmodificationswithinthecoastalzone.Themostapparenthumanactivityhasbeenthedredgingofaboatchannelontheoceansideadjacenttothecoprawarehouse.Thischannelisusedduring the loadingandunloadingof field tripshipsandby traditionalcanoes fishing in the leeof theisland.Itislikelytheboatchannelhasinfluencedreefflatcirculationandwaveprocesses.However,asthechannelisshallowanddoesnotextendtotheislandshoreline,itisunlikelytoplayasignificantroleiserosionofinundationoftheadjacentshoreline.Assessment:Anyfuturemodificationtotheboatchannelshouldincludeadetailedassessmentpriortocommencement.Theimpactsofchannelwideningordeepeningonthecirculation,sedimenttransportandwavepropagationwouldneedtobecarefullyassessed.Otherhumanmodificationswithinthecoastalzoneincludethereclamationofswampsneartheairportinordertoextendtheroad.Communitygroupssuggestthefillingoftheswamphashaddetrimentalimpactonbothfisheriesandlocalerosion.WithinthedenselypopulateddowntownareaofNamdrikthereisevidenceoferosionandsubsequentattemptsofshorelinestabilizationwithanadhocriprapwall.Thiswall,locatedinfrontofthemayorshouseiscomprisedofrecycledconcretefromthedemolishedoldschool.

Figure X. The boat channel on the western side of Namdrik atoll has altered reef flat circulation patterns. Any further modification to the boat channel should only follow a detailed assessment of possible effects on wave attenuation and reef flat circulation which could impact erosion on neighboring shorelines.

Figure X. A local solution to erosion and inundation control involves piling of organic debris, largely coconut husks along the shoreline adjacent to a house. This approach is likely to fail as buoyant organic material will likely to washed away during periods of high water levels.

Assessment:Anyfutureconstructionofseawallsoranystructuresonthebeachshouldcarefullyconsidertheflowoneffectstoadjacentsectionsoftheshoreline.3.2ShorelineErosionThecommunityindicatesthaterosionhasbeenobservedoverthepast20yearsintwoparticularareas:the airport and the downtown. There is increasing concern regarding the impacts of erosion onbuildings, graves, and property. In the northern region of Namdrik, they estimate erosion ofapproximately32feet(tworowsofcoconuttrees)onthelagoonside,where,graveshavestartedtofallintothe lagoon. TheyassociatetheerosionherewiththefillingoftheNorthernswamp,anareathatconnectsdowntown to theairport,whichwas constructed in1982. In thedowntownarea, coconuttreesand Japaneseshadetrees (?)arebeingundercut. People indicatethatthebeachusedtobe20feetseaward.ThelargetreeshadbeenplantedbytheJapanese,priortotheSecondWorldWar.

Figure X. Erosion to the lagoon shoreline adjacent to the community center has resulted in many Coconut and Pandanus tree toppling into the lagoon. The root balls of the remaining Coconut palms tend to focus wave energy towards unprotected sections of the shoreline, encouraging further erosion. In the downtown region, sand has been mined by the residents for construction, including thedispensary(1999),cementhomes(USDAhousingbeganin2005),cementcisterns,andmostrecentlyforthenewschool (2007).Thecycloneof1979destroyed95%houses,andhouseswererebuilt,someofthembeingmadeofcement,otherswithplywood. Traditionalhousesweremadeofwood,thatchedroofs,andwereelevatedarenotcommonnow,however,therearesome inthemidatollarea. Inthenorthern end, the source of the marsh fill in the 1980s was likely the beach as well, which wouldcorrespondtotheerosionobservations.Thetreesbeingundercutbyerosionexacerbatetheproblem,sincetherootshavebeenabletohelpstabilizethebeach.Thesetreesactaregroynes,directingincidentwaveenergyintosoft,unconsolidatedpocketsofsand.Tips:ThebulkoftheinformationonshorelineerosionatNamdrikwasobtainedthroughthecommunityconsultation phaseof theReimaanlok.Resourcemapping, timelines andgeneraldiscussionswith thecommunityweretheprimesourcesofthe information. It isrecommendedthatReimaanlokteamstakeinterpretivewalkswithcommunitymembers,promptingconversationson shorelinechange.Obviouslytheoutputsarehighlyqualitativeand subject tobias,butwithanabsenceofother toolsReimaanlokteamsmustrelyonthecommunitytoobtainnecessaryinformation.CorrectiveActionstaken:TheMayorindicatesthatsandfortheschoolandotherprojectsisnowtakenfrom the ocean side, not the lagoon side. There has been some corrective action taken by threeindividuallandownerstobuildwallstoprotecttheirpropertyfromfloodinganderosion.Oneconsistsofrockspiledonthebeach,whileanotheriscoconuthusksandsmallrocks(FiguresXandX).

Figure X. Unless carefully planned, designed and constructed ad hoc seawalls are likely to promote erosion in adjoining sections of the shoreline. A coastal plan is recommended to ensure effective use of coastal protections to mitigate hazards such as erosion and inundation. Assessment:Itishighlylikelythaterosionwillcontinueandpossiblyaccelerategiventhelikelihoodofacceleratedsealevelrise.Itisuncertainifstorminesswillincrease,whichcouldbringepisodesoferosion.Carefulmanagementoflocalsandminingneedstobeconsideredtoreduceimpactswithinthecoastalzone.Sandandaggregateshouldbesourcedfromareasofthelagoonwherematerialdoesnotcontributetothebeachsystem.Thisiseithera)sandfromdeepersectionsofthelagoon,orb)sandfromreefflatdepositsbetweenMadmadandthetipofNamdrik(NAME)3.3StormandtidalinducedfloodingThehistoricaltimelineindicatesthatflooding(approximately3feet)uptotheroadinthedowntownareaoccurredduringtheJanuary2007Kingtides.Duringthe2005Kingtides,cropsweredamagedextensively.Inadditiontothetidalflooding,thecommunityrecallstyphoonsin1957(100%homeslost,majorcroploss,andthelocaltapiocadidnotrecover),1979(95%homeslost,cropsdamaged,fallentrees,saltwatercontaminationofwells),and1991(northernreefpinnacleoceansidebrokenoff,lossofgiantclamscollectionareaandspearfishingareas).Thecommunityindicatesthatwhiletheyhavereceivedwarningabouthighwindsassociatedwithcyclone,theydonotreceivewarningoftidalsurge

orfloodingpotential.OneoftheareasthatfloodsregularlyisdowntownneartheCatholicandProtestantChurches.CorrectiveActionstaken:Therehasbeensomecorrectiveactiontakenbythreeindividuallandownerstobuildwallstoprotecttheirpropertyfromfloodinganderosion.Oneconsistsofrockspiledonthebeach,whileanotheriscoconuthusksandsmallrocks.Intermsofcropdamage,peoplehavewashedtheircropswithfreshwaterfollowingtheflood.SomeofthenewUSDAhouseshavefoundationsthatareapproximately812abovegroundlevel.Thetraditionalhousesareelevatedonwoodenstilts,butarenolongerbuilt.Thereisoneconcretehouseindowntownthatiselevatedapproximately???feet.Assessment:Futuresealevelrisewillincreasethefrequencyandmagnitudeofinundationandflooding.Giventhelowelevationofpopulatedareas(lagoonwardoftheroad)itislikelythatsmallincreasesinsealevelwillresultinregularflooding.Topographicprofilingindicatesthatlargesectionsoftheislandarepresentlyatoraroundtheverticallimitofpresentdaysealevel.Itislikelythatanyadditionalsealevelrise,whichisconsideredhighlylikely,willresultinregularinundationwithintheseareas.Optionstoaddressthishazardinclude:

Ceaseanynewconstructionwithinthemostvulnerableareas(lagoonwardofroad). Relocationofhousestohighersectionsoftheisland(seawardside). Constructionofhousesresilienttoflooding(raisedhousing). Carefulmanagementofgroundwaterresources,salinityandlevelshouldbemonitoredto

determineanyimpactsofsaltwaterintrusion. Efficientcollectionandstorageofrainwaterincisterns/tanksshouldcontinuetobe

encouragedtoprepareforlikelyintrusionofsaltwaterintogroundwater. Constructionofseawallsalonglagoonshoreline. Introductionofsalttolerantcropsinvulnerableareas.

KeyFindings

Erosionisacriticalissuetothecommunitywhoestimateratesapproximately1ft/yralongthelagooncoast.ThereisevidenceofongoingerosionwithrecenterosionscarpsandCoconutpalmsclosetobeingfullyundercut.

Floodingoccursduringstormsandduringseasonalkingtides. Floodingdrivenbylagoonwavesisrareduetothefetchlimitedconditions.

Occasionalstormsarelikelytohavecatastrophicimpactsontheisland,itsinfrastructureandresidents.Communityconsultationsuggestover95%ofhousesweredestroyedduringatyphoonin1979.