Strategy Summary 2025 by Coastal Partners

HaylingIsland

CoastalManagementStrategy–Preparingforaresilientfuture

TheStrategywasproducedforHavantBorough CouncilbyCoastalPartnerswithtechnicalassistance fromtheengineeringconsultantAECOM.

ThisprojectwasfundedbytheEnvironmentAgency fromFDGiA(FloodDefenceGrantinAid)andby HavantBoroughCouncilthroughLocalLevy.

GlossaryandAcronyms

Chapter1:Introduction

Introduction

StrategyObjectives

TheShorelineManagementPlanHierarchy

ShorelineManagementPlanPolicies

TheNeedforaStrategicApproach

PurposeandStructureofthisDocument

Chapter2:WhatisatRiskifweDoNothing?

BaselineScenario–DoNothing

WhatisatriskifweDoNothing?

SeaLevelRiseandIncreasingRisk

Erosion

Chapter3:HowTheStrategyhasbeendeveloped

OverviewoftheStrategyarea–keyfeatures,issuesandopportunities

CoastalProcessesOverview

CoastalLandfillSites

EnvironmentalDesignations

HeritageandRecreation

StakeholderEngagement

ExistingDefences

ABriefHistoryofCoastalManagementonHaylingIsland

BeachManagementonHaylingIsland

StrategyDevelopment

Chapter4:StrategyOverview

Aphasedapproachtomanagementbasedonrisk DeliveringMore–broaderoutcomesandcontributions Adaptation

Chapter5:CoastalManagementStrategy

WhatcanIexpecttoseeforeachODU?

AdaptivePathways

ODU1–LangstoneBridgetoNorthneyFarm

ODU2–NorthneyMarina

ODU3–NorthneyFarmtoChichesterRoad

ODU4–ChichesterRoadtoMillRytheJuniorSchool

ODU5–MillRytheJuniorSchooltoSalternsLane

ODU6–SalternsLanetoWilsonsBoatYard

ODU7–WilsonsBoatYardtoFisheryCreek

ODU8–Eastoke

ODU9–EastokeCornertoInnontheBeach

ODU10–InnontheBeachtoNorthShoreRoad

ODU11–NorthShoreRoad

ODU12–NorthShoreRoadtoNewtown

ODU13–Newtown

ODU14–NewtowntoStoke

ODU15–StoketoLangstoneBridgeCarpark

ODU16–LangstoneBridgeCarparktoLangstoneBridge

Adaptation

Changingourlifestyles,economy,infrastructureandlocalplacestomakeus moreresilientandadaptabletofutureconsequences.Ref:NationalFCERM StrategyforEngland(2020)

https://www.gov.uk/government/publications/national-flood-and-coastalerosion-risk-management-strategy-for-england--2

Adaptivepathwaysapproach

Adaptivepathway’sisadecision-makingapproachthatallowsdecision-makers totakeactionstomanageriskunderuncertaintyandchangingconditionsnow andintothefuture.

AnnualExceedanceProbability(AEP)

Isthepercentageofoccurrenceinanyyear.Forexample,a0.5%AEPfloodhas a0.5%or1in200chanceofoccurringinanygivenyear.

Baseline

Definesanexistingcondition/situation(usuallyDoNothing)againstwhich optionsorscenariosarecompared.

Bi-modalwaves

Abimodalseastateoccurswhenbothswellwaves(lowerinheightbuthavea longerwaveperiod)andlocallygeneratedstormwaves(highwaveheightsbut shorterwaveperiod)arepresent.Theyresultinaveryenergeticwave spectrumthatcanbeverydamagingtothecoastline.Formoreinformationon howthesewavesimpactHaylingIslandvisitBimodalSummary—Coastal Partners.

CashValue

Undiscountedcostsordamages(presentedintoday’scashterms).

HabitatCreationandRestorationProgramme

IsastrategicprogrammerunbytheEnvironmentAgencytodeliverhabitat compensationforlossesasaresultofShorelinemanagementPlanpolicies.

HTL(HoldtheLine)

Apolicywithanoverarchingintenttobuildormaintaincoastaldefencessothat thepositionoftheshorelineremainswhereitcurrentlyis.

Improve

Thisisatermwhichreferstoraisingexistingdefencelevelsorbuildingnew defencesataraisedheighttoaddressfuturesealevelriseriskstoday.

Leachate

Aliquidthatabsorbscontaminantsfromthesoilasitpassesthrough.Leachateis relevanttocontaminatedlandstudiesandcantransportcontaminatedmaterials (i.e.heavymetals)totheshoreline.

Maintain

Thisisatermwhichreferstoproactivelymaintainingdefencesatthecurrent defenceheight.

ManagedRealignment(MR)

Allowingtheshorelinetomovenaturallybutmanagingtheprocesstodirectitin certainareas.Thisisusuallydoneinlow-lyingareasbutmayoccasionallyapplyto cliffs.

NationalLandscape

Areplaceswithnationalimportance,protectedforthenation'sbenefit.Formally knownasAreasofOutstandingNaturalBeauty.

NoActiveIntervention(NAI)orDoNothing

Noplannedinvestmentindefendingagainstfloodingorerosion,whetherornot acoastaldefencehasexistedpreviously.

OptionDevelopmentUnit(ODU)

Asectionofthecoastlineinwhichlocalscaleoptionstomanagefloodand erosionriskaredeveloped.

PresentValue

Costsordamageswhichincludediscountingthroughtime.PresentValuecosts anddamagesareadoptedinthebenefitcostratioandfundingassessment.

PropertyFloodResilience(PFR)

Floodmitigationmeasuresappliedtoindividualpropertiesthatreducetherisk offloodingonapropertylevel(i.e.doorflooddefendersetc).

Residuallife

Thetimeleft(typicallyinyears)thatadefencestructurehasbeforeitcomesto theendofitsservicelife.Theresiduallifeisestimatedfromadefence conditionsurveyandassumesthatnomaintenanceworkswillbecarriedoutin thefuture.

Resilience

Thecapacityofpeopleandplacestoplanfor,betterprotect,respondto,and recoverfromfloodingandcoastalchange.Ref:NationalFCERMStrategyfor England(2020)https://www.gov.uk/government/publications/national-floodand-coastal-erosion-risk-management-strategy-for-england--2.Resilience measurescanincludeinitiativessuchasCoastalChangeManagementAreas (CCMAs),PropertyFloodResilience(PLR)andpolicychanges.

Scheme

Ameasure,orcombinationofmeasuresundertakentoincreasethelevelof protectionagainstfloodinganderosiontoalocalarea(i.e.anewfloodwall structure).

SMP(ShorelineManagementPlan)

Ahigh-levelnon-statutoryplanningdocumentwhichprovidesabroadscale assessmentoftheriskassociatedwithcoastalfloodinganderosionand presentsalong-termpolicyframeworktoreducetheseriskstopeopleandthe developed,historicandnaturalenvironmentinasustainablemanner.

StandardofProtection(SoP)

Theleveloffloodriskthatacoastaldefencestructureisdesignedtoprotect against.Thelikelihoodthatacertainleveloffloodingwilloccurisdescribedas the'chance'thatalocationwillfloodinanyoneyear.Thisriskcanbeexpressed asa1in100(1%)chanceoffloodinginanyoneyear,ora1in200(0.5%) chance,andsoon.Inanyoneyearalarge(0.5%)floodeventhaslesschanceof happeningthanasmaller1%or2%floodevent.

Sustain

Thisisatermwhichreferstooptionsthatkeeppacewithchange(e.g.sea levelrise).Thisisachievedbyraisingorupgradingdefencesinthefuture.

StrategicCoastalManagementApproaches

•AcceptingtheTide:Allowingthecoasttoevolvenaturally,noactive management.

•KeepingOuttheTide:Controllingnaturalprocesseswithharddefences, toprotectpropertiesbehindthedefence.

•WorkingwiththeTide:Workingwithnaturalprocessesandreinstating naturaldefencessuchassaltmarshes.

•AdaptingtotheTide:Adaptingtoachangingenvironment,forexample bymovingdefenceslandwardorrelocatingproperty.

GunnerPoint

AEP AnnualExceedanceProbability

BMP BeachManagementPlan

EA EnvironmentAgency

HBCHavantBoroughCouncil

FCERM Flood&CoastalErosionRiskManagement

HCCHampshireCountyCouncil

HCRP HabitatCreation&RestorationProgramme

HTLHoldTheLine

LNR LocalNatureReserve

MRManagedRealignment

NAINoActiveIntervention

NENaturalEngland

ODUOptionDevelopmentUnit

PLRPropertyLevelResilience

PV PresentValue

SACSpecialAreasofConservation

SEAStrategicEnvironmentalAssessment

SMPShorelineManagementPlan

SoPStandardofProtection

SPA SpecialProtectionAreas

SSSI SitesofSpecialScientificInterest

UKCP UnitedKingdomClimateChangePredictions

Chapter1: Introduction

Introduction

CoastalPartnersandEngineeringandEnvironmentalConsultancyAECOMhas developedaCoastalFloodandErosionRiskManagementStrategyforHayling Island(hereafterreferredtoasTheStrategy)onbehalfofHavantBorough Council(HBC).

HaylingIslandhasapopulationofmorethan17,000andislocatedonthesouth HampshirecoastwithintheBoroughofHavant.Theislandhasa38kmcoastline, characterisedbybothahighlydynamicwavedominatedopencoastareaand moreshelteredtidallydominatedareaswithintheharbours.Theislandislow lyingwithamixoflanduseincludingrural,agriculturalanddenselypopulated urbanareas.Accessandegressonandofftheislandisviaasoleroadbridge connectiontothemainland(A3023).

TheStrategyareacontainsamixofresidentialandcommercialproperties. Therearelargeareasofopenspaceandsitesofsignificantenvironmental importancearoundmuchofthefrontage.Inaddition,therearehistorical landmarksandhigh-gradeagriculturalland.Thisdiverseandinterestingcoastal environmentprovidesextensiveaccessandrecreationopportunitiesandis widelyusedforleisurebyasignificantnumberofvisitorseachyear.Hayling Island’sbeachesarepopularwithswimmers,surfers,sailorsandwalkersalike, withtheseafrontstretchingover5kilometres,plustheshorelinesofLangstone andChichesterharbours.BeachlandsisaEuropeanBlueFlagbeachandisthe maintouristattraction.Withuninterruptedviewsacrossthesea,itispossible toseetheIsleofWight,andtowatchtheferriesastheypassenrouteto continentalEurope.

ManypartsofTheStrategyfrontagearealreadydefended;however,the condition,StandardofProtectionagainstfloodingandexpectedlifeofthese defencesishighlyvariable.Thismeansthatsignificantareasoflandacross HaylingIslandareatriskoffloodingfromlargestormevents.Partsoftheopen coastarepotentiallyatthreatfromcoastalerosion.

Inthefuture,withtheincreasedstorminessandrisingsealevelsthatare predictedasaconsequenceofclimatechange,theriskofcoastalfloodingand erosionislikelytoincreasesignificantly.

WITHOUTACTIVELYIMPLEMENTINGMEASURESTOMANAGE

FLOODANDEROSIONRISKS,OVER3,000PROPERTIESARE LIKELYTOBEATRISKBY2120.

Justover40%oftheislands’flooddefencesareprivatelymaintainedwithan assortmentofdefencestructuretypes.Theremainderaremaintainedbythe EnvironmentAgency,HBCandHampshireCountyCouncil(HCC).HBCalso undertakebeachmanagementalongtheopencoastsectionatEastokewith nourishmentandrecyclingactivities.Manyoftheseassetsarecomingtothe endoftheirresiduallife,requiringsignificantinvestmenttowithstandthe impactsofclimatechangeinthefuture.

Withalloftheinteractingandcompetingpressuresonthecoastlinethe primaryobjectiveofTheStrategyistoprovidealong-termplantoreducethe riskofcoastalfloodinganderosiontopeople,thedevelopedandnatural environmentforthenext100years.

Itachievesthisbyidentifyingasuiteofleadingoptionstomanageandreduce theserisksinacosteffective,holisticandsustainablemanner.

Implementationoftheseoptionsgoingforwardwill,however, besubjecttofundingavailabilityandtogainingrequired consents,sothereisnoguaranteethatoptionspresentedinthis Strategywillbeprogressed.

Pleasevisithttps://coastalpartners.org.uk/project/hayling-island-coastalmanagement-strategy-16/forfurtherdetails.

StrategyObjectives

TheaimoftheHaylingIslandCoastalManagementStrategyisto:

•DevelopstrategiccoastalmanagementoptionsforHayling Islandforthenext100years.

•Outlineaprogrammeofinvestmenttoreducetheriskof coastalfloodinganderosiontopeoplelivingontheisland.

•Identifythepotentialfundingsourcesandpartnersrequired todeliverthatinvestmentprogrammeandbeopenand honestaboutwherefundingislikelytobeachallenge.

•Incorporateadaptationstrategies,asdefenceimprovements willnotbepossibleinalllocations.

•Beholistic,yetflexibleforbothpeopleandnature.

•Respondtofuturechanges,supportsustainabledevelopment oftheislandandtakeintoaccountpredictedsealevel riseandclimatechange.

•Makeapartnershipapproachcentral,betweenHBC, EnvironmentAgency,NaturalEngland,landowners, businessesandlocalcommunities,makingsurelocalneeds andprioritiesareatitscore.

ShorelineManagementPlans(SMPs)sitatthetopofthehierarchyofplansfor managingcoastalfloodinganderosion.

AShorelineManagementPlan(SMP)isahigh-levelnon-statutoryplanning documentwhichprovidesabroadassessmentoftherisksassociatedwith coastalprocessesandpresentsalong-termpolicyframeworktoreducethese riskstopeopleandthedeveloped,historicandnaturalenvironmentina sustainablemanner.

AnSMPaimstomanageriskbyemployingarangeofmethodswhichreflect bothnationalandlocalpriorities,to:

•Reducethethreatofcoastalfloodinganderosiontopeopleandtheir property;and

•Benefittheenvironment,societyandtheeconomyasfaraspossible,inline withtheGovernment’s‘sustainabledevelopmentprinciples’.

TheStrategyareafallswithintheboundariesoftheNorthSolentSMP(2010).

ThisSMPpresentsthehigh-levelpoliciesforfuturemanagementofthe coastline.Thesepolicieswerefinalisedfollowingaperiodofpublicconsultation andwereformallyapprovedbytheEnvironmentAgencyandadoptedby HavantBoroughCouncilin2011.

TheSMPpolicyforthemajorityofthecoastlinealongthenorth,eastandsouth ofHaylingIslandistoHoldtheLineforthecomingcentury.Thesesectionsof coastlineincludethepotentialthreatoferosionandcoastalfloodingtothe mainurbanareas,landimportantforagricultureandaccessto/fromtheisland. Thispolicymeansthatthereisanoverarchingintent,subjecttomoredetailed studiesandfunding,istocontinuetodefendsothatthepositionofthe shorelineremainswhereitiscurrently.

Inordertomaintainkeyhabitatsandenhancethenaturalenvironmentthere arealsoareasinthewestofthefrontagewheretheSMPpolicyistoallow naturalprocesstocontinue(NoActiveIntervention).Thispolicymeansthatthe shorelinewillcontinuetoevolvenaturallyinthefutureandthatnonew defenceswillbebuilt.

TheSMPpoliciesforHaylingIslandareshownoverleaf.Whilsttheseindicatea HoldTheLinepolicyforthemajorityoftheHaylingIslandfrontage,thisdoes notmeanthatthispolicyappliesforthenext100years.TheSMPpoliciesfor thedifferentepochsarefurtherdetailedforthedifferentfrontagesin Chapter5.

TheNorthSolentSMPisavailabletoviewatShorelineManagementPlanShorelineManagementPlan(northsolentsmp.co.uk).

TheNeedforaStrategicApproach

Coastalstrategiessitatthesecondtierinthehierarchyofcoastalmanagement anditistheroleofstrategiestoidentifytheappropriateschemeorrisk mitigationoptionforimplementingtheSMPpolicies.TheStrategyreviewsthe SMPpoliciesinmoredetailtoensurethesehigh-levelpoliciesremain appropriateatthelocalscale.

TheStrategyconsidershowfloodanderosionriskislikelytochangeinthefuture inresponsetochangesinclimateanddevelopssustainableandrobustoptionsto managetherisksassociatedwithcoastalfloodinganderosion.Thisapproach ensuresthattechnicallyfeasible,environmentallyacceptableandeconomically viableoptionsarerecommendedtoreducetherisksfromcoastalfloodingand erosiontopeople,theirpropertiesandtheenvironment.Thisalsoensuresthat theoptionsarecompatiblewiththethoseofadjacentareas.

Withoutsuchanapproach,itislikelythatcurrentmanagementapproaches wouldcontinueintheshorttermandfuturecoastaldefenceworkswouldbe managedonan‘ad-hoc’orreactivebasiswhichwouldleadtopoorcost efficiencyandageneralincreaseinthefloodanderosionriskovertime.A Strategyisalsoimportanttodeliveranintegratedapproachtothemanagement ofourcoastline.Holisticwider-levelthinkingbehindStrategydecisionsensures thatthemanagementoptionsimplementedinoneareadonotincreasetheflood anderosionriskinadjacentareas,andthatopportunitiestodeliverwider benefitsarenotmissed.

HowTheStrategyfitsinthemanagementofcoastalfloodanderosionrisk

Theoutputs

TheStrategyisrequiredinordertohelpusgainapprovalforfuture schemes.However,itisimportanttonotethatthereisnoguaranteethat anyoftheoptionsrecommendedinTheStrategywillbeprogressed. Implementationofoptionswillbesubjecttofundingavailabilityandto gainingrequiredconsents.Publicfundsforcoastalmanagementarenot widelyavailable,sosignificantfundingfromavarietyofsourceswillbe neededtoprogressanyoptionsinthisStrategy.

FollowingaStrategy,avarietyofoutputscanresult,dependingonthelevelof riskandthepreferredoptionsputforward.Todeliverastrategicoptionitmay benecessarytoimplementascheme(e.g.buildnewdefences)toaddress coastalfloodanderosionrisks.Beforeworkshappenontheground,afurther elementofworkiscarriedouttodesigntheschemeanddeliverthebusiness caseforfunding.Wewillworktodevelopbusinesscasestoprogressschemes ifthereisfundingandifitisinthepublicinterest,wherethereisatechnical, environmental,socialandeconomicsolution.

Inotherareas,thefutureactionmayincludemaintenance,beach managementorevento‘DoNothing’ifappropriate.Theremayalsobeactions suchasmonitoring,planningandfurtherstudiesinordertogainevidenceto helpmakerobustmanagementdecisionsinthefuture.Thiscouldincludethe needforadaptationwhichfocussesonadjustingto,andmanaging,theimpacts offloodingandcoastalerosion.

PurposeandStructureofthisDocument

Thisdocumentsetsouttherecommendedoptionsformanagingcoastalflood anderosionriskonHaylingIslandforthenext100years.IndevelopingThe Strategy,anunderstandingofthepresent-dayriskhasbeendevelopedalong withhowitmightchangeinthefutureandthewaysinwhichwecanmanage andadapttothesechanges.Specifically,thisdocumentincludes:

Chapter2–Understandingwhatisatrisk

•Asummaryofwhatisatrisknowandinthefuture(definingthebaseline). Includinganassessmentofwhatwouldhappenifwe‘donothing’andhow theriskschangeovertimeasaresultofpredictedclimatechangeandsea levelrise.ThissetsthecontextforwhyweneedTheStrategy.

Chapter3–DevelopingTheStrategy

•Overviewofthestudyarea-KeyFeatures,IssuesandOpportunities.This identifiesthekeyaspectsandcharacteristicsofthestudyareawhichThe Strategyhasconsidered.Thisincludescoastalprocesses,potentially contaminatedland,theenvironment,stakeholderengagementand aspirations,andasummaryoftheexistingdefences.

•Adescriptionoftheoptiondevelopmentandappraisalprocess.Includinga summaryofhowthestrategicoptionsweredevelopedandappraised consideringtheireconomicandenvironmentalsustainability.

Chapter4–Strategyoverview

•AsummaryofTheStrategy–therationalebehinddecisionsanddiscussion ofthekeyprinciples.

•Anoverviewofthekeyeconomic,environmentalandbroaderoutcomesof TheStrategy.

•Howiscoastalfloodanderosionriskmanagementfunded–Thisincludes detailsofhowpartnershipfundingworksforFlooddefenceschemesinthe UKandthelikelihoodoffundingforthepriorityschemesidentifiedinThe Strategy.

•Deliveringmore.Howwehavebeenworkingwithotherorganisationsto tryanddelivermoreforyourcoastline.

Chapters5–HaylingIslandCoastalManagementStrategyoptions

Providesarea-by-areasummariesofwhatisatrisk,theleadingstrategic optionstoreducefuturecoastalfloodanderosionriskalongsideroutemaps andadaptivepathwaysforeacharea.

Chapter6–Short-termactionplan

Atimelineoftheshort-termfutureprojectactivitiesandindicativemilestones.

Chapter2: WhatisatRiskifweDo Nothing?

Gaininganunderstandingofthefloodanderosionriskalongtheshorelineis imperativeinordertodefineabaselinefordevelopingTheStrategy.Itallows comparisonstobemadebetweenthepotentialstrategyoptionsandisan essentialstepinTheStrategydevelopmentprocess.Thebaselinewasestablished byconsideringa‘DoNothing’scenario.

The‘DoNothing’scenarioisdefinedas:“Wherethereisnofurtherinterventionof anykind,includingnoemergencyresponseorwarningsystem.Wherethereare assetsatpresentorwheremaintenanceactivitiesorotherinterventionsare carriedout,theoptionwillbetowithdrawallactivities,allowingnaturetotake itscourse”.

Inessence,the‘DoNothing’scenariorepresentsahypotheticalsituation wherebyallexistingdefencesareabandonedintermsofmaintenanceorrepair, andnoremedialoradditionalprotectionworksarecarriedout.Inaddition, adaptationtosealevelriseorotherclimatechangeresponsesarenotaddressed.

ForthepurposeofTheStrategy,therisksposedbycoastalfloodinganderosion overthenext100yearshavebeenestablishedusingEnvironmentAgency approvednumericalfloodmodellingandCoastalPartnerserosionpredictions.It shouldbenotedthatevenwiththeexistingdefencesinplace;futurefloodrisk willincreasesignificantlyduetoclimatechangeandrisingsealevels.

Throughdeterminingthepresentandfuturefloodanderosionrisksundera‘Do Nothing’scenario,theproperties,features,assetsandkeyinfrastructurethatare atriskofdamageoverthenext100yearshavebeenidentifiedandvalued,after whichtheleadingstrategyoptionstomanagetheserisksweredeveloped.The assetsatriskinclude(butarenotlimitedto)servicesasvariedascropproduction andraisinglivestock,climateregulation,coastalhazards,tourismandrecreation, aestheticvaluesandwildspeciesdiversityandhabitats.FloodingatLangstone BridgewouldaffectaccesstoandfromtheIsland,andpopulartrailssuchasthe HaylingBillyTrailwouldalsobeunderthreat.Areasoflandfillcoulderodeand causeharmtotheenvironment.

Propertiesatriskofcoastalfloodingoverthecomingcenturyifwe‘DoNothing’. Basedon1:200year(0.5%annualchance)floodevent.

Propertiesatriskofcoastalerosionoverthecomingcenturyifwe‘DoNothing’.

ThereareanumberofstrategicissuesforcoastalmanagementonHayling Island,includingtheinfluenceofclimatechange,landfillsiteswhichareactively erodingandopportunitiesforhabitatcreation.Inordertomanageandaddress theseissues,itisconsideredimperativetodevelopanFCERMStrategy.Joinedupstrategicthinkingisrequiredtodevelopacohesive,efficient,longtermplan. TheStrategythereforeoutlinestheforwardprogrammeofworkstomost effectively,holisticallyandsustainablymanagethecoastalfloodanderosion relatedrisksfacingtheislandoverthenext100years.

Keyassetsatriskfromfloodinganderosion

*2125FutureTidalFlooding,assumingnodefences.

Pleasenote,thislistcontainsonlyasampleofassets atrisk,andisnotexhaustive.

SeaLevelRiseandIncreasingRisk

Asaconsequenceofclimatechangeandcontinuedwarmingoftheglobal oceans,sealevelsareexpectedtoincreaseinthefuture.Thiswillsignificantly increasetidalfloodandcoastalerosionriskacrossTheStrategyfrontageover thenext100years.

Toconsidersealevelrise,TheStrategyhasincorporatedthelatestsealevelrise projections(UKClimateProjections2018UKClimateProjections(UKCP)-Met Office)intothefloodmodellingtoproduce‘DoNothing’floodscenariosfor 2045,2075and2125.Followingthelatestguidelines,underthe‘medium emissions’sealevelrisescenario,meansealevelsacrossTheStrategyfrontage areexpectedtoincreasebyapproximately1moverthecomingcentury.

Aswellasproperties,therearemanyotherimportantfeaturesandvaluable assetsatrisk.Thisincludesschools,churches,publichouses,nationally importantenvironmentallydesignatedsites,heritageassets,militaryassets,key servicesinfrastructure,majorroads,coastalfootpathsandcyclewaysand shinglebeaches.Thereisalsoariskoferosiontoformerlandfillsiteswhich couldposeafurtherthreattohumanhealthandtothequalityofthe harbours.

Whatismeantbyfloodrisk?

Floodriskreferstothepotentialforexperiencingflooding.Thisriskisoften describedbythelikelihoodorchancethatacertainleveloffloodingwilloccur atanygivenlocation.Thisriskcanbeexpressedintermsofanaveragereturn periodinyears.Thisriskcanbeexpressedasa1in100(1%)chanceof floodinginanyoneyear,ora1in200(0.5%)chance,andsoon.

Chanceisalsorelatedtothescaleoftheflooding.Inanyoneyearalarge(1in 200year)floodeventhasstatisticallylesschanceofhappeningthanasmaller 1in50or1in20yrfloodevent.Itisimportanttounderstandthata1in100 chanceoffloodingdoesnotmeanthatafloodwillonlyhappenonceevery 100years.Thechanceremainsthesameeveryyear.Throughoutthis documentthescaleoffloodriskisdescribedintermsoftheaveragereturn periodinyears. TheStandardofProtection(SoP)offeredbyadefenceisalsodescribedin termsoftheeventthatitisdesignedtopreventfloodingfrom.Forexample,if aschemeprovidesa1in100year(1%annualchance)StandardofProtection itmeansitwillbedesignedtopreventfloodingfromalleventsuptothis magnitude.

MuchofthefrontagealongHaylingIslandisprotectedbyman-madecoastal defences.Theseareoftenfrontedbyinter-tidalmudflats,saltmarshesand beacheswhichworktoreduceerosionriskalongthecoastline.Without theseman-madeandnaturalseadefences,theislandwouldbeunderthreat fromerosion,mostnotablyontheopencoastcomparedwiththeharbours.

SeveralsitesaroundHaylingIslandarealreadyeroding,andmoresitescould becomevulnerableduringthenext100yearsifnoactionistaken.For example,partsoftheHaylingBillytrailmayhavetoberelocateddueto futureerosion.Thereisariskthatformerlandfillsitesalongthecoastline, bothdomesticandindustrial,couldwash-outasaconsequenceofsealevel riseandcoastalerosionwithoutsuitablemanagementorremediation.

Erosionalongthewestcoastwouldalsoimpactsiteswhichareimportantfor over-winteringbirds;alongthesoutherncoast,propertiesandbusinesses alongtheseafrontcouldbeaffected.

Erosiononthewestcoast(ABOVE)andeastcoast(BELOW)ofHaylingIsland

Whatismeantbyerosionrisk?

ForthepurposesofTheStrategy,propertiesorassetsatriskoferosionare thosewhichcouldpotentiallybelosttotheseathroughshorelineretreat duetotheactionofwaves,currentsortides.Theriskhasbeenestimated assumingnofurtherworksaredonetorepairormaintaindefenceswhich currentlyprovideprotection.

Understandingthepotentialerosionriskunderahypothetical‘DoNothing’ scenario’isimportantforcomparingtherelativemeritsofoptionsto maintainorimproveprotection.

Chapter3: HowtheStrategyhas beendeveloped

Beforestrategicapproachestomanagingfloodanderosionthreatscanbe identifiedandevaluated,itisimportanttounderstandthekeyfeatures,issues andopportunitiesthatexistwithinTheStrategyarea.Inordertoachievethis,a numberofstudiesandactivitieswereundertakenduringtheearlystagesof developingTheStrategy.

Theseincluded:

•Engagementwithkeystakeholders,residentsandthewidercommunity–meaningfulengagementwithlandowners,communitygroups,organisations andindividualstounderstandtheiraspirationsandconcerns,tohelpshape TheStrategy;

•Sitewalkoversandvisualassetinspections–todeterminethelocation,type andconditionofcoastaldefencesandassets;

•Astudyofcoastalprocesses–requiredtounderstandwaves,tides,sediment movementsandtolookatthelonger-termfloodanderosionrisktoboththe openandharbourcoastlines;

•Desktopassessmentoflandfillsites–toidentifyareasalongthefrontage whichmayrequiredefendingtopreventthemerodingandharmingthe environment;

•Identificationofimportantenvironmentalandheritagefeaturesaroundthe Island–sothatkeyenvironmentalobjectivesandlegalrequirementsto protecttheenvironmentcanbeaccountedforinTheStrategy;

•Identifyingpotentialbroaderoutcomesandopportunities–inorderto captureideasastohowTheStrategycanbefundedaswellasdeliverwider benefitstocommunities.

Asummaryofthefindingsoftheseactivitiesrequiredtounderstandthebaseline forTheStrategyisprovidedinthischapter.

MuchofHaylingIslandhasbeenreclaimedovertheyears,resultinginlow lyinglandwithsignificantareasatriskoftidalflooding.Thisisexacerbated ontheopencoastwhenstormandswellwavescombinetoproducebimodalwaveconditions.

ManyofthefloodeventsexperiencedinthepastonHaylingIslandhave occurredinthesouth-easterncorneroftheislandwherethecoastlineis mostexposedtotheimpactsofwaveconditions.Theshelterednorthern partsoftheislandinsidetheharboursarepronetofloodingfromtidalsurges ratherthanlargewaveaction.Residentialroadsandextensiveareasof grazinglandhavefloodedinthepast.Floodinghasalsohistoricallyoccurred adjacenttotheA3023approachtoLangstoneBridge.Thesituationwillbe exacerbatedinthefuturewithsealevelrise.

Theopencoastisalsomorevulnerabletoerosion,duetowaveaction.

TheHaylingIslandcoastlinethatsitswithinChichesterandLangstone Harboursiscomprisedofmostlymudflats,withsomesaltmarsh.Saltmarsh habitathasbeenerodinginbothharbourssincethe1940s,althoughtherate oflosshasslowedsincethemid-1980s.Duetothenarrowharbour entrances,largeswellandwindwavesarenoteasilyabletopropagatealong theentrancechannelsintotheharbours.Therefore,theriskofcoastal damage,floodinganderosionfromwaveattackinsidetheharbourislimited. Fortheharbours,thegreatestriskisfromextremewaterlevels,ratherthan fromwaveaction.

TheopenbeachalongthesouthcoastofHaylingIslandoffersavery differentsituation.Ithasalonghistoryofhighenergywaveaction,which resultsinsignificantbeachdrawdown,cutbackandlossofmaterial.

HaylingIslandisunusualtootherlocationsinthatitsbeachesaresusceptible tobi-modalwaveconditions,whenlongperiodswellwavesrefractaround theIsleofWight,coincidingwithlocalstormconditions.Theyresultinvery energeticwaveconditionsthatcanbeverydamagingtothecoastline.

TheStrategyrecognisestheimpactsofbi-modalwavesinrelationtofuture management,butmoredetailedresearchonbi-modalwaveswillneedtobe undertakentoinformthedesignofanynewdefencesalongHayling'scoast.

GunnerPoint

CoastalLandfillSites

Inthecoastalzonethepresenceoflandfillisariskbecauseerosionoftheshoreline,or flooding,canreleaselandfillintotheenvironmentthroughexposureandleaching.Ifnot dealtwithadequately,thismaterialcanposeathreattotheenvironment.

ThereareeightformercoastallandfillsitesonHaylingIsland.Adesktopstudywas undertakeninordertoclassifyeachofthesesitesasbeingeitherhigh,moderateorlow risk.

Theriskwasbasedontheprobabilityandconsequenceoflandfillbeingreleased througherosionorasaresultoftidalflooding.TwositeswereclassifiedasbeingatHigh Risk,fouratModerateRisk,andtwoatLowRisk.

TheevidencefromthisstudywasconsideredduringthedevelopmentoftheLeading StrategyOptions.Optionstomitigatetheseriskswereidentifiedandconsideredinthe appraisals.

ExamplesoflandfillatsitesaroundHaylingIsland

EnvironmentalDesignations

HaylingIslandissurroundedbydesignatedsites,includingtheChichesterand LangstoneHarboursSpecialProtectionArea(SPA)/RamsarsiteandtheSolent MaritimeSpecialAreaofConservation(SAC).ChichesterHarbourisalso designatedasaNationalLandscapeandSinahCommonisadesignatedSSSI (SiteofSpecialScientificInterest).HaylingIslandalsosupportsfiveLocalNature Reserves(LNR),includingTheKenchandtheHaylingBillyLNR.Manyofthese importantsitesaresituatedalongTheStrategycoastlineandassuchitis essentialtoconsidertheseareaswhendevelopingTheStrategy.

Withinmanyoftheseimportantsitesthereareanumberofdifferenthabitats suchassaltmarshesandmudflatswhichsupportawidediversityofwildlife. Theintertidalmudflatsprovideaparticularlyimportantfeedinghabitatfor birds.PartsoftheislandarealsoidentifiedasBrentGooseandWaderfeeding androostingsites.

Unfortunately,withpredictedsealevelrise,itisthoughtthatmanyofthe importantintertidalhabitatswillget‘squeezed’againstcoastaldefence structuressuchasseawalls.Thiscandecreasethesizeandhealthofthe intertidalhabitatsandplaceadditionalstressesonthespeciesthatrelyupon them.

ThereisalegalrequirementundertheHabitatCompensationandRestoration Programme(HCRP)tocreatenewintertidalhabitatwithintheNorthSolent ShorelineManagementPlanarea,tooffsetthelossofexistingintertidal habitatsviacoastalsqueezeinfrontofalltheHoldtheLinepolicyareas.To helpoffsettheseanticipatedlossesinthefuture,itisessentialforTheStrategy toconsiderenvironmentalimprovementoptionsandinvestigateopportunities tocreatenewareasofhabitat.

ViewsofSolentMaritimeSACandChichesterHarbourSPA,RamsarandSSSI (ABOVE)andKenchLocalNatureReserve(BELOW)

HeritageandRecreation

TheIslandplayedavitalroleduringWorldWarII,whenitbecameanimportant militarybasewithasignificantroleinthedefenceofPortsmouthandinthe build-upto,andexecutionof,theD-DayLandings.Theseactivitieshaveleft theirmarkonthecoastallandscapeofHayling,andpillboxes,gunsitesand memorialscanstillbeseentoday.

HaylingIslandisoftenconsideredasoneoftheUK’slasttraditionalseaside resorts.ThelistedRoyalHotelbuiltin1825,alongwithanearbyBathHouse andbathingmachinesattractedwealthyholidaymakerstotheIsland.By1909, beachhutsandbathingtentswereestablishedalongtheHaylingIslandbeach.

TheHaylingBillyLinewasanimportantconnection,bringingtouriststothe island.Asaresult,holidaycampsflourishedduringthe1950s.Today,the HaylingBillytrailrunsalongtheoldrailwaylinefromthenorthoftheIsland downtoSinahLane.Itiswellusedbywalkers,cyclistsandhorseriders.

HaylingIslandoffersarichcultural,historicandenvironmentallegacyasa leisuredestinationwhosegenesisasapre-Victorianexclusivehealthresort evolvedintomasstourismandthedevelopmentoftheholidaycamps.This formedthefoundationofawater-sportsoffer,basedaroundbeingthe worldwidehomeofwindsurfing,followinglocalresidentPeterChilvers’ inventionofthefirstwindsurfboardin1958.Haylingisideallysituatedfora varietyofwatersports,duetoitbeingshelteredbytheIsleofWight.Such sportsincludesailing,windsurfing,powerboating,jetskiing,paddleboarding, kitesurfingandkayaking.

Paragliding-oneofthemany activitiesonofferonHayling Island’sbeaches

ManyindividualsandorganisationshaveakeyinterestorstakeintheHayling Islandcoastlineformanydifferentreasons.Eachstakeholderisthereforelikelyto haveauniqueviewonitsuse,developmentandfutureprotection.Assuch stakeholderengagementisfundamentalandcanbeasourceofindispensable informationwhichcanbeusedtodefinecoastalissuesandobjectives,steer Strategydevelopmentandachieveconsensusonthefuturemanagementofthe coastline.

Strategydevelopmentsetoutandimplementedaclearmethodologyforengaging withlocalcommunities,businessesandpublicbodieswithavestedinterestinthe HaylingIslandcoastline.Thisapproachensuresthatthosewhomayaffectorare influencedbythedecisionsofTheStrategyareactivelyinvolvedandinformedat therighttime.TheaimsofTheStrategyengagementprocesswere:

•toraiseanawarenessandunderstandingofcoastalfloodanderosionrisknow andintothefuturewithclimatechange

•toidentifythechallengesandconstraints

•toidentifybroaderoutcomeopportunities

•todevelopcommunityinvolvementinthedecision-makingprocessfor managingourcoastline.

•tolistentotheircommentsandconcerns

Stakeholderandpublicengagementhasinformedthecoastalmanagement optionsbearinginmindwhatistechnicallyfeasible,publiclyacceptable, economicallyviableandenvironmentallyacceptable.

Atthelaunchoftheproject,apublicsurveywasinitiatedtoseekthecommunity’s viewsoncoastalmanagementofHaylingIsland.Respondentswereaskedabout theirconcerns,whatisimportanttothemwhenusingthecoastlineandtheir aspirationsfortheisland.Theresultsofthesurveyhelpedusunderstandthe communities'viewsoncoastalfloodanderosionriskontheisland,wherethe mainareasofconcernwereandwhatwidercoastalopportunitiespeoplewould liketosee.

FourvirtualsessionswereheldduringdevelopmentofTheStrategy,withthe projects'KeyStakeholderGroup,madeupofrepresentativesofthelocal community,including;residents,localbusinesses,landowners,andcommunity groups,organisationsandlocalCouncillors.Thefirstsessionprovidedan introductiontotheproject,opportunitytomeettheteamandtofindoutwhya Strategyisneededandwhatisinvolved.Thenexttwovirtualworkshop sessionshelpeddetermineaspirationsandopportunitiesrelatingtoHayling Island’scoastline.Thefinalvirtualsessionprovidedanopportunitytopreview thedraftStrategyandaskquestionsbeforethestartofpublicconsultationin October2022. Theprojectteamhavealsoheldanumberofvirtualmeetingswithlandowners alongHayling'scoastlinetounderstandhowtheyusetheirsectionofcoastand establishtheirshortandlong-termaspirationsfortheirfrontages.

Throughpresentations,questionandanswersessionsandothervirtual meetings,TheStrategyteamhaslearntahugeamountabouthowpeoplewish toseetheshorelineevolve.Alloftherelevantfeedbackreceivedtodatehas beenusedtoinformthedevelopmentofTheStrategytoensurethatit accountsforandcaptureskeystakeholderinputandideas.

Apublicconsultationperiodranforthreemonthsbetween3October2022and 30December2022.Thefeedbackreceivedduringthistimewasassessedand whereapplicableandrelevantusedtoupdateoramendthefinalStrategy. Whilstmanyofthecommentsreceivedwerenotdirectlyrelatedtothe Strategyproposalstheyhavebeenextremelyusefultohighlightmanyother communityissues,concerns,opportunitiesandsuccesses.

Inaddition,theStrategysupportingenvironmentalreportsweresubjectto statutoryconsultationwithNaturalEngland,theEnvironmentAgencyand HistoricEngland.TheStrategyhasbeenupdatedtotakeaccountofthe statutoryconsulteecommentsreceived.

ExistingDefences

TohelpestablishthebaselinefloodanderosionrisksalongTheStrategy frontageitwasnecessarytoidentifytheconditionoftheexistingdefencesand howlongtheyarelikelytolastwithoutmaintenance.Thiswasdoneby undertakingawalkoveroftheentireStrategyshorelineandvisuallyassessing defenceconditioninlinewiththeEnvironmentAgency'sassessmentmanual.

Thereisawiderangeofdifferentdefencetypes,fromearthembankmentson muchoftheeastandwestcoasts,toseawallsandrevetmentsalongthemore exposedopencoastwhichprotectagainsterosionandwaveovertopping.In addition,theopencoastisaffordedprotectionbythebeacheswhichactasa barriertothewaves,however,theyrequireregularmanagementtomaintain thebeachlevelsastheyareanintegralpartofthedefencesystem.

ApproximatelytwothirdsofthedefencesaroundHaylingIslandareownedand maintainedbyprivatelandowners.

Landownersareultimatelyresponsibleformaintainingorimprovingtheir owndefences.Therefore,wheremaintenanceorupgradeofdefencesis referredtoinTheStrategyitisassumedthatthiswillcontinuetobethe Landownersresponsibility.

Whoisresponsibleformanagingthecoastline?

CoastalProtectionAuthoritiesandtheEnvironmentAgencyhavepermissive powerstocarryoutworkstoprotectagainstcoastalfloodinganderosion. However,thisisnotalegalobligation.ThismeansHBChasthe'power'tocarry outcoastalprotectionworksbutisnotdutyboundtodosoandwillnotbeliable forthefailuretoexercisethesepowers.

Ingeneral,LocalAuthoritiesandtheEnvironmentAgencywillonlyactwhere thereisawidepublicbenefitand/oranappropriateengineeringsolutionthatis achievable.ThisiswhyHBCarecommittedtothisStrategytounderstandwhat canbedonetoprepareHaylingforamoreresilientfuture.

Approximately70%ofthedefencesaroundtheislandareestimatedtobeina fair,poororverypoorconditionwithashortresiduallifeorprovidealow standardofprotection.Consequently,thereareanumberofcriticalareas aroundtheIslandwherethedefenceshavefailedorarebeginningtofail,some frontingareasoflandfill.

Duringthe1940s,HaylingIsland becameatouristdestination. Initialdefenceswere constructedinorderto maintainthelineofthebeach. Overtime,naturalretreatand lossofmaterialfromthebeach meantitwasnecessarytobuild moresubstantialdefences,to protectthepropertiesbehind.

1947:constructionofnew seawall,Eastoke

1960sand1970s:floodingandproperty damageinEastoke

The1960sand1970ssawlargewaves overtoptheseawall,andcause extremefloodingandsignificant damagetoproperties.Upgraded concretedefenceshadcausedthe drawdownofthebeachinfront, underminingthedefenceand increasingtheincidenceandseverity offlooding.Significantrepairswere carriedouttotheseawallin1978to repairstormdamage.

Priorto1985,lowbeachlevelsledto morerunupofseawatertothe seawall.Significantovertoppingby wavesoverthedefencesledtolarge floodingeventsatEastoke.In1985, 510,000m³ofshinglewasplacedon thebeachasthefirstcampaignof beachmanagementonHayling,ata costofapproximately£4m.Thisbuilt upthebeachlevelsandreducedthe riskofwaveovertoppingand flooding.

1985:thefirst campaignofbeach management

The1990ssawthestartofannual beachmanagement,whichwas carriedoutasthepreferred managementoption.

Beachmanagementoperations involvingrecyclingaswellas importingmaterialhavecontinued. Thisactivityhelpsmaintainbeach levelswhichreducestheimpactof stormwaves.Somebeach overtoppingoccurs,whichis retainedonthepromenadewitha controlledflowtotheroad drainage.In2013,theEastokePoint Scheme,involvingtheconstruction ofthreerockgroynesandrock revetment,wasimplementedto addressbeachloweringand increasedfloodrisk.

BeachManagementonHaylingIsland

PresentDayBeachManagement

£5.1millionhasbeensecuredfromtheEnvironmentAgencytoimplementa BeachManagementPlan(BMP)alongtheHaylingIslandfrontageforthenext fiveyearsto2029.

TheSouthHaylingBMPhasidentifiedastrategyfordeliveringthebeach managementapproachalongtheopencoast.Itsetsouttherequirementsfor maintenance,monitoringandinterventiontomaintainthebeachand structurestoensuretheycontinuetoprovideanadequatestandardof protectionalongtheEastokefrontage.

TheCouncilimplementstheBMPtoretainahealthybeach,withoutwhichwe wouldseethereturnofregularseriousfloodingatEastoke,asoccurredbefore the1985beachrechargeworks.

DredgingActivitiesandBeachNourishment

Oneofthemethodsappliedtothebeachmanagementactivitiesisbeach nourishment,whichisthereplacementofsedimentlostfromasectionof beach.Thisisachievedprimarilythroughusingeitherbeachrechargeorbeach recycling.Thiswillhelptorestoreadepletedbeachbacktoacceptablelevels.

Restoredbeachlevelscontributetoreducingtheimpactofstormwaves,which inturnhelptomanageflooding.

Beachrecharge:materialissourcedfromoutsidethenormalbeachsediment systemandintroducedtothesamenearshorezone.

Beachrecycling:Materialismovedfromanareaofaccretiontoanareaof erosion,torestoreadepletedbeachbacktoacceptablelevels.

Beach recharge, 2019

©SolentSky Services, 2019

Beach recycling, 2023

Ondefiningthebaseline,andhavinggainedadetailedunderstandingoftheprocesses,featuresandissuesoperatingalongthecoast,thedevelopmentandappraisal ofstrategicmanagementoptionswasundertaken.

TheoptiondevelopmentprocessreferstothetasksinvolvedtoselecttheleadingstrategyoptionsalongTheStrategyfrontage.Theprocessfollowedthe EnvironmentAgency’sNationalFloodandCoastalErosionRiskManagementguidelines.

Definebaselinescoping anddatacollection

Defineoption developmentunits(ODUs)

Identifyalonglistof possiblemeasuresfor eachODU

Selectpreferredpackages ofmeasuresfromthe ODUshortlistto implementthestrategic options

Developpotential strategicoptionsforeach ODU

Definethebaselinefor eachODU

Conceptuallyappraisethe longlistofmeasures

Detailedappraisalof strategyoptionsbyODU

Selectionand confirmationofthedraft leadingoptions

ProjectBoardapprovalof draftstrategyfor consultation

Identifyshortlistoptions foreachODU(atoolbox ofviablemeasuresto implementstrategic options)

Publicandregulator consultation

EnvironmentAgency reviewandapprovalof thefinalstrategy

HBCapprovalofthefinal strategy

Review,feedbackand updatethestrategy

StrategyDevelopment

OptionDevelopmentUnits

Floodanderosionrisks,coastaldefencetypes,landuses,landownershipandissuesandopportunities varyalongTheStrategyfrontage.Foreffectivefloodanderosionriskmanagementoptionstobe developeditisimportanttoconsiderandrecognisethislocalvariability.Withthisinmind,thefirst stageoftheoptiondevelopmentprocesswastodividethefrontageintosmall,localsections.These sectionsareknownasOptionDevelopmentUnits(ODUs).

OptionDevelopmentUnits

ODU1:LangstoneBridgetoNorthneyFarm(split into3sub-unitsa-c)

ODU2:NorthneyMarina

ODU3:NorthneyFarmtoChichesterRoad

ODU4:ChichesterRoadtoMillRytheJuniorSchool

ODU5:MillRytheJuniorSchooltoSalternsLane (splitinto3sub-unitsa-c)

ODU6:SalternsLanetoWilsonsBoatYard

ODU7:WilsonsBoatYardtoFisheryCreek

ODU8:Eastoke

ODU9:EastokeCornertoInnontheBeach

ODU10:InnontheBeachtoNorthShoreRoad

ODU11:NorthShoreRoad

ODU12:NorthShoreRoadtoNewtown

ODU13:Newtown

ODU14:NewtowntoStoke

ODU15:StoketoLangstoneBridgeCarPark

ODU16:LangstoneBridgeCarParktoLangstone Bridge

CoastalManagementApproaches

Thelonglistofoptionsfallwithinthefollowingstrategicapproaches.

AcceptingtheTide

Allowingthecoasttoevolvenaturally,noactivemanagement

ThisapproachisconsideredasthebaselinefortheHaylingStrategy.Itinvolves nointerventionormanagement,wherethecoastisallowedtoeffectively evolvenaturally.Beachesandsaltmarshhabitatsareabletomovelandward naturallyassealevelsrise,erosionisunconstrained,andfloodingwillbecome deeperandmorefrequentovertime.

Thiswillnotbeappropriateeverywhere,especiallyinbuiltupareas,butis moreaboutacceptingtheriskofflooding.

KeepingOuttheTide

Controllingnaturalprocesseswithharddefences

Thisapproachinvolvesbuildingartificialstructureswhichtrytocontrolnatural processes.Theseoften‘hard’defencesaredesignedtoreduceerosionorhold backthetide. Theycannotprotectagainsteverystormeventualityandsodonotstop floodingcompletely,thereisalwaysstillarisk.Theyareallbuiltwithadesign lifeandwillnotbesustainableforever.Overtimeandassealevelsrise, beacheswilldisappear,andnaturalsaltmarshwillreduceasitissqueezed againstdefences(knownascoastalsqueeze).

Saltmarshhabitats movelandward

Morefrequent floodingBeachesmovelandward

Erosioneventsmorefrequent

Acceptingthetide

Keepingoutthetide

Embankments

Seawalls

Revetments

Rock

Methodsofkeepingoutthetideinclude:

•Seawalls–asseeninfrontofInnontheBeach,HaylingBillycarparkin thenorthandMenghamRythesailingclub;

•Timberorrockrevetments–asseenatthecoastguardstationandjust southofMenghamRythesailingclub;

•Embankments–asseeninvariouslocationsonboththeeastandwest coastsofHaylingIsland.

Underthisapproach,thelevelofchangeinriskovertimewithdifferent optionsisalsoconsidered,inordertofindthebestsolution.Optionsthat Maintain,SustainorImprovethecurrentlevelofprotectionareconsidered.

WorkingwiththeTide

Workingwithnaturalprocessesandreinstatingnaturaldefences

Byworkingwithnaturalprocessesratherthanagainstthem,thisapproach takesamoresustainableandnaturalapproachtomanagingthecoast.

Methodsofworkingwiththetideinclude:

•Beachmanagement–bymovingmaterialfromareasofaccretiontoareasof erosionandbuildingupthebeachafterstorms.Thisneedstobecarriedout frequently.ThismethodiscurrentlyinusealongHayling’sopencoast.

•Beachordunenourishment–wherenewmaterialisplacedonthebeach,or plantingtostabilisedunes.ThebeachatEastokeisnourishedregularly, usingdredgedmaterialfromaboat.

•Groynes–totrapsedimentandbuildupabeach.Thismethodcanhave negativeeffectsbystarvingotherareasofmaterialcausingerosion elsewhere.TherearerockandtimbergroynesalongHayling’sopencoast.

Maintain:Proactivelymaintaindefencesatthecurrentdefenceheight ortomanageerosion.Sealevelriseriskisnotaddressed.

Sustain:Adaptdefencesovertime,byraisingorreinforcingdefences instages.Addressessealevelriseriskinanadaptiveway.

Improve:Raiseexistingdefencelevelsorbuildnewdefences. Addressesfuturesealevelriskrisks,today.

•Offshorebreakwaters–helpstrapbeachmateriallandwardofthe breakwater.Thismethodis,however,onlyeffectiveforwaveovertopping, notfloodinundation.

•Saltmarshrestoration-reinstatinganaturaldefenceagainstfloodingand erosionbyrestoringsaltmarshhabitats.Thisoptionwillappealmoretothe harbourcoasts.

Saltmarshrestoration

Groynes

StrategyDevelopment

AdaptingtotheTide

Adaptingtoachangingenvironment

Thisapproachfocusesonmanagingchange,tominimisethenegative consequencesoffloodinganderosion,whereadaptationtoachanging environmentoccursbymakingcommunitiesmoreresilienttoclimate change.

Itcaninvolve:

•Makingspacetoallowbeachestorollbacklandwardnaturallyassea levelsrise;

•Adaptingpropertysoitismoreresilienttoflooding;

•Makingmodificationsinsideandoutsidetoreduceimpacts;

•Floodwarningandfloodplans;

•Relocatingpropertyorotherassetssuchascarparks;

•Changinglanduses.

Thisapproachhasthepotentialtoprovidenewopportunitiessuchas creatingnewhabitatswheredefencesaremovedbacktomakespacefor thetide.

StrategicOptions

ToassesstherelativemeritsofdifferentStrategyoptions,thebaselinefloodand erosionriskimpactsassociatedwitha‘DoNothing’approachwerederivedineach ODUforthepresentday,2045,2075and2125.Thisallowedforidentificationof theriskareaswithineachODU,andthetimingofrisksdefined.Thisformeda basisfromwhichtodevelopanumberofpotential‘strategicoptions’forfloodand erosionriskmanagement.Theoptionsconsideredincluded:

•DoNothing(baseline–developedineachODU)

•DoMinimum–e.g.maintenanceandrepairs–leastrequiredtoimplement theSMPpolicy

•Maintain–e.g.continuetoprotectagainsterosion

•Sustain–maintainaminimumstandardofprotection(SoP)byraising defencesovertimetokeeppacewithsealevelrise

•DelaySustain–maximiseexistingdefencesthenraiseSoPofdefencesata laterdate

•ImproveSoP–improveSoPcomparedtopresentday

Foreachstrategicoption,anappropriate‘packageofmeasures’foreachODUwas selectedforeachODU.Each‘package’wasproducedinconjunctionwiththeshort listofoptionsandoutlinedthetypeofcoastaldefencestructureandtimingof worksrequiredoverthenext100yearstoimplementthestrategicoption.

StrategyDevelopment

StrategyOptionsAppraisal

AppraisalofthestrategicoptionsineachODUincludedeconomicappraisal(Benefit:Costanalysis),anumberofenvironmentalassessmentsandatechnical appraisalofeachstrategicoption.Thismulti-variateappraisalofoptionswasundertakentoensurethattheleadingoptionsputforwardmeetTheStrategy objectivesandarerobustandsustainableintechnical,social,environmentalandeconomicterms.

Assess options againstkey criteria

StrategyDevelopment

Technicalconsiderations

AprimaryconsiderationinthedevelopmentofaStrategyistoknowwhatoptionsbeingrecommendedaretechnicallyviable.Thereislittlepointinundertaking detailedeconomicandenvironmentalappraisals,orputtingtheoptionforward,iftheoptioninquestioncannotreasonablybeimplementedontheground. Technicalconsiderationsincludeaspectssuchasthedefencetypeinquestion,timingofworks,spaceandheightrequirements,allinthecontextofthelocation andpresentconditionofthesiteinquestion.Forexample,foracurrentlyundefended,openspacelocation,therearefewtechnicalissues,andarangeofoptions arelikelytobetechnicallyviable(e.g.revetments,seawalls,landraising,floodwallsearthbundsetc.).However,foramoreconstrainedsite,suchasadenseurban environmentwherespacemaybeverylimited,significanttechnicalchallengesmaybepresentformanyoptions(e.g.landraisingorearthbundswhichrequires space)andmaylimittechnicallyfeasibleoptionstothosesuchasafloodwallwhichrequireasmallerfootprinttoimplement.

Socialaspects

TwoonlineworkshopswereheldinNovember2020withkeystakeholders representingorganisations,communitygroupsandlandownersonHayling Island,focussingonunderstandingandcapturingaspirations,ideasand opportunitiesforHayling’scoastalandharbourfrontages,todayandinthe future. Theseresultshelpedustounderstandwhatisimportanttothosethatlive onandvisitHaylingIsland.Theideas,suggestionsandaspirations identified,directlyinformedthedevelopmentofthestrategicoptions alongsidewideropportunitieswhichcouldpotentiallybedelivered alongsidefloodanderosionriskmanagementschemesinthefuture.The optionappraisalprocessaccountedfortheseaspirationsandthereisan intentthatthepreferredoptionsbeingputforwardshouldsupportand facilitatethesewherepossible.

Environmentalaspects

Thekeyenvironmentalconsiderationsandobjectiveshelpedshapethestrategy options.ThiswasachievedthroughaStrategicEnvironmentalAssessment(SEA) whichwasundertakenasanintegralpartoftheoptionappraisalprocess.AnSEA Scopingreportwasconsultedonduringtheearlypartoftheproject,andthekey environmentalobjectivesfortheprojectwereconfirmedandthesewererelated tothefollowingcategories:

•Biodiversity

•Culturalheritageandarchaeology

•Landscape

•Populationandhumanhealth

•Soil

•Water

•Air

•Climate

•Materialassets

•Andtheinterrelationshipbetweentheabovefactors

Theoptionswerethenappraisedinrelationtoeachcategory’sobjectivesandthe environmentalimpactsoftheoptionsweredetermined.Thisinformationwasthen includedaspartoftheevidenceforselectingthepreferredoption.Wherepossible itisintendedthatthepreferredoptionsshouldnotsignificantlydetrimentthe achievementoftheenvironmentalobjectives,butiftheydo,suitablemitigationor compensationmustbeidentifiedinordertoensuretheoptionsare environmentallyacceptable.

SandyPoint

Theeconomicassessmentformedanimportantpartoftheselectionofthe leadingstrategyoptions.Althoughtheleadingoptiondoesnotnecessarilyhave todeliverthemostcosteffectiveoption,becausetherearemanyother determiningfactors(e.g.socialandenvironmentaldrivers),itishowever importanttomakesurethepreferredoptionmakeseconomicsense(i.e.the benefitsofdoingsomethingoutweighthecosts).

Thestrategyoptionsweresubjecttoeconomictestingduringtheappraisal.The assessmentinvolvedanestimationoftheBenefit:Costratioofeachoption.

Thecostsofanoptionwereestimatedaccordingtothedefencetypes(as indicatedbythe‘packageofmeasures’),andthedefencelengthsandheights. Thefloodanderosionbenefitsofastrategyoptionweredeterminedby calculatingthedamagesavoidedcomparedtothebaseline‘DoNothing’ scenario. Generallyspeaking,thehighertheBenefit:Costratio,themoreeconomically viablethestrategyoption.TheBenefit:Costratiowasusedasatooltohelp informthedecision,andforStrategypurposesaslongasanoptionhada Benefit:Costratiogreaterthan1(i.e.thebenefitsoutweighthecost)itwas deemedaCostEffectiveOption.Sometimesmorecostlyoptionsprovide additionalbenefits,andiftheserepresentbettervalueoveralessexpensive option(i.e.theadditionaldamagesavoidedoutweighthecosts),thenitmay havebeenpreferabletochoosethismorecostlyoption,knownastheWider ObjectivesOption.

ForeachODUanoverall‘leadingoption’hasbeenselectedastheoption whichscoredthehighestintheappraisal.ForthemajorityofODUsthe leadingoptionwillbeeitherthe‘costeffectiveoption’ORthe‘wider objectivesoption’,butinasmallnumberofODUs,thecosteffectiveoption andthewiderobjectivesoptionarethesame,astheyhaveequalscores.

CostEffective Option

WiderObjectives Option

Thisistheoptionwhichprovides bestvaluefortaxpayers’money inlinewithgovernmentpolicy andguidance.

Thisoptionmeetsthemost objectives(environmental,social andtechnical)usingascored multi-criteriaapproach.

Itshouldbenotedthatalthoughmanagementoptionsmaybe economicallyviableforthepurposesofTheStrategy,itdoesnotmean theywillgoahead;therequiredfundingtopayfortheschemesmuststill befound.

costsordamageswhichincludediscountingthroughtime. PresentValuecostsanddamagesareadoptedinthebenefitcostratio andfundingassessment

Chapter4: StrategyOverview

StrategyOverview

Aphasedapproachtomanagementbasedonrisk

TheStrategyoptionsproportionatelyaddressfloodanderosionriskswith worksphasedovertimedependingontherisk-basedtriggers.Assealevelsrise inthefuture,andexistingdefencesreachtheendoftheirusefullife,new coastaldefenceswillberequired.TheStrategyhasrecommendedaphased implementationprogrammeforfutureworks,basedonwhenrisksmaterialise.

TheStrategyrecommendsthatfuturefloodriskmanagementintervention optionssustainaminimum1:75year(1.33%annualchance)standardof protection(SoP).Thisstandardhasbeeneconomicallytestedagainst alternativesanditisdemonstratedthat1:75year(1.33%annualchance) minimumSoPisappropriateandeconomicallysoundatthestrategiclevel. Itshouldalsobenotedthatthisstrategiclevelminimumstandardof protectionwillbereviewedandtestedonalocalscaleinthedevelopmentof specificschemes;thismayresultinhigherstandardsofprotectionbeing deliveredlocally.

Schematicshowingadaptivemanagementwithaphasedinterventionovertime tomaintainaminimumSoP

Howwillfuturemanagementbepaidfor?

Inrecentyearstherehasbeenachangetothewaycoastaldefencesare funded.Thefundingsystem,referredtoasapaymentforoutcomesapproach, rewardspartnershipfundingofschemesandprovidesmanypositivebenefits withlotsmoreschemesnowbeingbuiltasaresult.

Althoughaverysmallminorityofschemescanstillgainapprovalfor100% publicfunding(GrantinAid),schemeswithanexternalcontributionarelooked onfavourablytoalsoattractpublicmonies.Inaddition,themeritsofschemes arenotjudgedpurelyfinancially,andthewideroutcomesthatascheme deliversarealsoconsidered.

Forexample,ifaschememovespeopleinhighlydeprivedareasoutof significantfloodrisk,thispropelstheschemeuptheladderinthebidforpublic funding.

TheStrategyrecommendseconomicallysoundleadingstrategicapproachesto managingfloodanderosionrisk.Althoughsomefutureschemesmaybeableto attractsomepublic(GrantinAid)funding,contributionswilloftenberequired tomakeuptheshortfalltoenableschemestoprogress.Byknowingthe potentialfuturecostsofworks,mechanismstoinvestigateandsecurefunding canbedeveloped. Suchcontributionscouldcomefrom:

•ACommunityInfrastructureLevy–wheredevelopersareeffectivelytaxed andthismoneyisspentoncommunityprojects

•Directlythroughdevelopers(e.g.raisinglandthroughredevelopment)

•PotentialBeneficiariesofSchemes–businessesandprivateindividuals

•Locallevies

•LocalEnterprisePartnership

•Othersources.

DeliveringMore–broaderoutcomesandcontributions

TheStrategyprimarilypresentstheleadingstrategicapproachesformanaging therisksposedbycoastalfloodinganderosion.However,indoingthis,there arealsomanyotheropportunitiesforTheStrategytoprotect,supportand facilitatewiderbenefits.ThisisakeyobjectiveofTheStrategy.

Forexample,anewcoastaldefencetoprotectanareafromfloodingcanbeas simpleasaseawall.Whilstsuchadefencewillserveitspurpose,withsome joinedupthinkingtheremaybeopportunitiestoprovidemultiplebenefitsand notjustaflooddefence.

Broaderoutcomesandopportunitiesforwiderbenefitsthatcouldbedelivered alongsidestandardcoastaldefenceschemeshavebeenexploredduring Strategydevelopment.Potentialfutureopportunitiesinclude:

Business,regenerationandgrowth

•Renewableenergyoptionssuchas,solar,windandtidal

•Asecondpubliccrossingtotheislandfromthemainland

•Regenerationopportunitiestoenhancetourism,leisureandbusiness

•Multi-usedefencesincorporatingcafes,shopsandbeachhuts

Healthandwellbeing

•Createaccessiblespaces

•Improveconnectivitythroughneworenhancednetworkoffootpathsand cyclingroutes

•Playareasandinformalactivityspaces

•Socialspotstoconnectkeyareas

Recreation,amenityandtourism

•Widenandraisebeachesforamenity

•Connectsiteswithpromenadesandfootpaths

•Createasenseoflocalidentityandplace

Environmentalenhancement

•Incorporatenatureintothedesignofcoastaldefencesusingtidalpools oreco-formliners

•Realigndefencestomakespacefornature

•Saltmarshplanting

•Createbirdislandsandinstallbirdhides

•Wildflowermeadowsandbeepoststoencouragebiodiversity

•Interpretationboards

Heritage

•Heritagetrailsandboardwalkstolinksites

•Educationandinterpretationboards

UnlikelytobepaidforbyGovernmentGrantinAid,thesebroaderoutcome andwiderbenefitopportunitiesthatcouldbedeliveredalongsideFCERM schemesmayinturnactuallyopenupotheravenuesoffundingas partnershipfundingcontributionstowiderschemes.

Inordertoseekthedeliveryofthesemultiplebenefitsoffuturedefence schemes,TheStrategyhasidentified,signpostedandbegunexploringthe opportunities.

Connectivity

Adaptation

TheStrategyoptionsprovidetherecommendedpathwaysformanagingtidal floodingandcoastalerosiononHaylingIslandoverthenext100years. However,theimplementationoftheseoptionsisdependentonfunding availability.Withoutthenecessaryfunding,itmaynotbepossibletoconstruct /maintainthedefences/measuresrecommendedbytheoptions.Thereality isthatwewillneedtolooktoadaptationasarealisticresponsetocoastalrisks ontheislandnowandintothefuture.

‘...anticipatingappropriateactiontoprevent orminimisethelikelihoodandconsequences offloodingandcoastalchange,bothnow andinthefuture…’

CoastaladaptationshouldbeconsideredinALLLOCATIONSalongsidethe leadingstrategicoptionspresentedinTheStrategy.Weneedtoexplore methodstoadjusttotherealityofpresentandfuturecoastalfloodingand erosionrisk.

Adaptationfocussesonadjustingto,andmanaging,theimpactsofflooding andcoastalerosion,asopposedtotheotherstrategicoptionswhichaimto mitigatetheimpactsthroughphysicalfloodprotectionmeasures.Waysin whichcommunitiescanadjusttocoastalfloodanderosionriskaspartofan adaptationapproachinclude:

•Creatingcommunityfloodsupportgroups

•Signinguptofloodwarningsystemsandevacuatingpriortofloodevents

•Riskinformedland-useplanning

•Relocation

•Propertyfloodresilience

CoastalAdaptation

NationalFCERMStrategy2020

LinkswiththeLocalPlan

ThestrategyisintegrallylinkedtotheproductionofHavantBorough’semerging ‘BuildingaBetterFuture’LocalPlanandtheimplementationoftheHavantBorough RegenerationandEconomyStrategy2022–2036.

TheLocalPlanisinearlystagesofpreparation.Itwilladdresstheneeds,constraints andopportunitiesfordevelopmentacrossallpartsoftheBorough,andsetouthow much,whattypeandwheredevelopmentwilltakeplace.

CoastalPartnershaveworkedcloselywiththeHBCPlanningPolicyTeam throughoutthedevelopmentofTheStrategytoensurestronglinkageswiththe LocalPlanandback.Plannersareconsideringfloodriskintheirsitesassessments. EmergingLocalPlanpolicyfordevelopmentonthecoastgivesinprinciplesupport toFCERMschemes,andthedefenceandhabitatcreationprojectsidentifiedinThe StrategyactionplanwillfeatureintheLocalPlanandtheBorough’sInfrastructure DeliveryPlan.Provisionofimprovedcoastaldefencesinthefuturewillhelpprotect thosepartsofHaylingIslandwhichwarrantitandmakesurethatalloftheisland canremainaccessibletoensureasustainablefutureforthispartoftheBorough. Therefore,theLocalPlanhasfedbackintotheStrategydevelopmentandits optionsinrelationtocriticalroadinfrastructureandhelpedtoshapetheleading optionsinkeyareasoftheisland.

Langstone Bridge

HBCemerging localplan

Chapter5: CoastalManagement Strategy

WhatcanIexpecttoseeforeachODU?

ForeachODUyouwillfindthefollowingfoursections:

Overview

ThissectionprovidesanoverviewofeachODUinrelationtoitslocation,key characteristics,defences(what,whoowns,whomaintainsandcondition), infrastructure(ifakeyfeature),coastalprocesses(ifrelevant)andenvironment (designationsandimportance).ThissectionalsoincludestheShoreline ManagementPlanPolicyforthefrontage.

Risk

Thissectionexplainswhatthemainriskisalongthefrontageinrelationtotidal floodingand/orcoastalerosion,andoutlineswhatisatriskovertheStrategy lifetimeinlightoffuturecoastalchangeandsealevelrise.

Twomapsareprovidedshowingthemodelledextentofanextremetidalflood event(1in200year,0.5%annualoccurrence),withoutanydefences,todayand in100years.The‘donothing’damagesforeachODUarealsoincludedinPresent Valueterms(i.e.damageshavebeendiscountedovertime).

LeadingOptionRoadmap

AleadingoptionroadmaphasbeenincludedforeachODU.WhereODU’shave beensplitfurther,theleadingoptionsforeachareincludedintheoverallODU roadmap.Eachroadmapincludesacost-effectiveoptionandawiderobjectives optionresultingfromtheassessmentsundertaken,asdescribedinSection3.

CostEffective Option

WiderObjectives

Option

Thisistheoptionwhichprovides bestvaluefortaxpayers’money inlinewithgovernmentpolicy andguidance.

Thisoptionmeetsthemost objectives(environmental,social andtechnical)usingascored multi-criteriaapproach.

Theroadmapforeachpresentsavisualrepresentationofthestrategy option(s)withthesymbolsusedasfollows:

Key

DoNothing

Nofurtherinvestmentinexistingcoastaldefences.Defenceswouldbe allowedtofailovertimeandnaturalprocessestocontinue.

Maintenance

Maximisethelifeofexistingcoastaldefencesatcurrentheightthrough patchandrepairandscheduledmaintenance.

CapitalWorks

Constructionofnewcoastaldefences/refurbishmentofexistingcoastal defences.

Sustaining/ImprovingDefences

Sustaining/Improvingexistingcoastaldefencesbyraisingtheheightor constructingadditionallengthsovertime,tokeeppacewithsealevel riseandincreasedrisk.

Set-backdefences

Constructionofasetbackdefencetoreducerisktoassets,alongside opportunitiesforintertidalhabitatcreation.

Adaptation

Adaptingtotheimpactsofcoastalfloodinganderosion.Thiscould includeanumberofofdifferentmeasures,suchaspropertyflood resilience,earlywarningsystems,relocationofassetsandriskinformed landplanning.

Inadditiontotheroadmap,atechnicaldescriptionoftheODU’s‘Overall StrategicOption’isprovided.

WhatcanIexpecttoseeforeachODU?

Adaptivepathways

ThissectionprovidestheAdaptivePathway’sforeachODUandforeachsub-sectionif applicable.

Weuseadaptivepathwaystohelpcommunicatethedifferentactionsavailabletousas coastalmanagers,especiallywherethereislittlejustificationforfundingatraditional FloodandCoastalErosionRiskManagementscheme.

Anadaptivepathwayapproachhasthereforebeenadoptedtoallowusmoreflexibility tomanagerisksandadapttochangingconditionsovertimeusingtriggerpointswhere adecisionisrequiredtoinstigateapotentialmovetoanotherpathway.

ForeachODUdiscretemanagementactionpathwaysandtriggerpointsareshown, appropriatetothatfrontage,highlightingtheleadingoptionpathwayasrecommended inthisStrategy.

Thissectionalsoincludesadescriptionofthestrategicintenttocoastalmanagement alongthefrontageandnextstepsfollowingStrategyapproval.

Forallfutureschemesrecommendedinthenextsteps,fundingwillbearealchallenge todelivery,soitisexpectedthatavarietyofsourcesoffundingwillberequired alongsideGovernmentGrantinAidinorderforanytoprogress.

ODU1:LangstoneBridgetoNorthneyFarm

Overview

ODU1islocatedbetweenLangstoneBridgeandNorthneyFarm.This frontageiscomplexgiventhetidalfloodrisk,varyinglandusesandland ownership.ODU1isdividedinto3sub-units.Sub-unit1Aisboundedby NorthneyRoad,andimportantagriculturalland,sub-unit1Bincludesapublic recreationalareafrontingresidentialpropertiesandsub-unit1Cisaformer landfillsite.Sub-unit1Aand1BareseparatedbyNorthneyMarinainODU2.

Defences

Theexistingembankmentsareexpectedtohaveshortremainingliveswhere theyexist,withresiduallivestypicallybetween10and20years,butinsome localisedareas,lessthan10years.Thesedefencesarecurrentlymaintained byHampshireHighways,HavantBoroughCouncil,theEnvironmentAgencyor privately.

Infrastructure

NorthneyroadisidentifiedasacriticalpieceofinfrastructureinHavant BoroughCouncil’sdraftlocalplanprovidinganalternativeemergencyaccess routeontotheisland.ItisalsocrucialtoaccessNorthneyvillageandmaintain theviabilityofNorthneyMarinaandtheLangstoneQuaysResortaswellas potentialfuturedevelopmentproposalsinthearea.Theroadisregularly inundatedthroughouttheyearandimpassableforhoursatatime.Thiswill becomemorefrequentinthefuturewithclimatechangeandsealevelrise.

Environment

Thefrontageiscoveredbysignificantenvironmentaldesignations,including SAC,SPA,RamsarandSSSIdesignationsonintertidalareas,aswellasSPA, RamsarandSSSIontheformerlandfillsite,andaNationalLandscapebothon landandintertidal.Thelandwardagriculturalandrecreationallandis importantasfunctionallylinkedhabitatforbirds,beingcore,primaryand secondarysupportareasintheSolentWadersandBrentGooseStrategy.

ShorelineManagementPlanPolicy

HoldtheLinepolicyalongthewholeofthisfrontageoverthenext100years.

Risk

Themainriskhereisfromtidalflooding,wherethefloodcelllinksODU1A,BandC.Overthenext100years,without defencesinplace,itisexpectedthatinadditiontotheregularinundationandlossofNorthneyRoad,therewillbeup to87propertiesatriskfromtidalfloodingacrosstheunit.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

OverallStrategicOption

Sustain0.5%AnnualExceedanceProbability (AEP)withmanagedrealignmenthybrid

StrategicIntent

TheStrategicintentfortheunitistoimplementafrontlinedefence toprotectNorthneyRoadsubjecttoobtainingconsents(ODU1A); setbackdefencesalongthecentralsectiontoallowforhabitat creationandnaturalevolutionoftheshoreline(ODU1B)and continuetodefendtheformercoastallandfill(ODU1C).Notonly doesthisprovidefloodriskprotectiontothepropertiesbyclosing thefloodriskcell,butitalsoprotectsthecriticalroad infrastructureandformerlandfillsitewhilstmakingspacefor naturewhereviabletodoso.IffrontlinedefencesalongNorthney Roadarenotlikelytobeconsented,thenset-backdefences combinedwithrelocationoftheroadshouldbeinvestigated.Also, ifthelandfillisfoundnottobeharmfultotheenvironment,then opportunitiestosetbackdefencesshouldalsobeinvestigated here.ItisworthnotingthatsomepartsoftheStrategicintent deviateawayfromtheSMPpolicytoHoldtheLinefor100years.

NextSteps

AFloodandCoastalErosionRiskManagementSchemeforNorthney hasbeenproposedintheStrategy’sshorttermactionplan.Subjectto securingfunding,thiswillstartwithafeasibilitystudytoappraise appropriatecoastalmanagementoptionsandalignmentsfordefences alongthisfrontageandinvestigatethepropertiesoftheformercoastal landfillsite.

ODU2:NorthneyMarina

Overview

ThisunitislocatedbetweenODU1Aand1BandencompassesNorthneyMarina andtheLangstoneQuaysResort.TheMarinacomplexincludesamixof businessesandmorerecently,anumberofresidentialproperties.Thereis potentialforfurtherdevelopmenthereinthefuture.

Defences

Existingdefences,wherepresent,areprivatelyownedandmaintainedinformal embankmentsandlocalisedrockarmour.Residuallivesofthesedefencesare typicallybetween15and20years.Thereareveryfewpropertiesatriskasthe marinaisonrelativelyhighland.

Environment

Thefrontageissurroundedbyasuiteofenvironmentaldesignations(Ramsar, SPA,SAC,SSSI)whichcovertheintertidalareasoutsideofthemarinaitself. Landward,themarinaandhotelfallwithintheChichesterHarbourNational Landscape.

ShorelineManagementPlanPolicy

HoldtheLinealongthewholeofthisfrontageoverthenext100years.

ODU2location

ODU2

Risk

Floodanderosionriskislowonthesiteitself,howevertheaccessroadtothefrontagealongNorthneyRoad (ODU1A)isatsignificantfloodrisknowandintothefuture.TheviabilityofNorthneyMarinaandsurrounding businesseswillthereforebehighlydependentonmaintainingaccesstothesiteviaNorthneyRoadintothe future.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5% annualprobability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

StrategicIntent

TheStrategicintentfortheunitisadaptationofassetstobecome moreresilienttoclimatechangeimpactsinthefutureasfloodand erosionriskisverylow.Iflandownerswishtomaintain(andfund) theirexistingdefencesinthefuture,theywillneedtoobtainthe relevantlicencesandconsentsfirst.

NextSteps

Noneidentifiedforthisfrontageintheshort-term,otherthanongoing conversationswithcommunitiesinrelationtolevelsofriskandwhat todointheeventofaflood.

ODU3:Northney FarmtoChichester Road

ODU3:NorthneyFarmtoChichesterRoad

Overview

ODU3islocatedbetweenNorthneyFarmandChichesterRoadand predominatelyfeaturesfarmland,withthevillageofNorthneysetbackfurther inland.

Defences

Thedefencesinthisunitareprivatelyownedandmaintainedandcomprise embankmentswithavarietyofharddefences,includingsheetpilingand concrete.Defencesarelocallyinapoorconditionwithveryshortremaining lives,typicallylessthan10yearsorfailing.Theagriculturallandbehindis significantlyimportantforlivestockgrazingandsafeguardingthethriving businessintothefutureiskey.

Environment

Thefrontageiscoveredbysignificantenvironmentaldesignations,bothon landandintheHarbourandfallswithintheChichesterHarbourNational Landscape.Thecoastalgrazingmarshareawithintheagriculturallandis designatedasSSSI,RamsarandSPA,providingtheidealhabitatforCurlew andotherwaterbirdstofeedandroostathightide.Whilethefronting intertidalareasareSSSI,Ramsar,SPAandSAC.LandwardoftheSSSI,SPA/ Ramsarareas,theagriculturallandisimportantfunctionallylinkedhabitat forbirds,beingcoreandprimarysupportareasintheSolentWadersand BrentGooseStrategy.

ShorelineManagementPlanPolicy

HoldtheLine,butnopublicfundingavailableforprivatedefencesinthe shortandmediumtermandundertakefurtherdetailedstudiestoconsider managedrealignmenttocreatenewintertidalhabitatinthelongterm.

Risk

Thereissignificanttidalfloodriskherewhichwillincreaseindepthandextentinthefuturewithsealevelrise.

Overthenext100years,itisexpectedthatupto87propertiesinNorthneyVillagewillbeatriskoftidalflooding ifnofloodriskmeasuresareimplemented.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5% annualprobability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

Donothing damages

£3,098,000 Presentvalue

StrategicIntent

Thestrategicintentfortheunitistobalancetheagriculturalneeds withfindingopportunitiestocreatehabitatinordertobothmaintain viabilityoftheagriculturaluseandhelpmeetthelegalrequirementfor restorationandcompensationofhabitatswithinChichesterHarbour. Thiswillrequireconstructionofnewset-backdefenceinphases,anda blendedmanagementapproachinclosecollaborationwithallpartners andwillhelptoreducefloodrisktopropertiesinNorthneyvillageover thenext100years.

Anadditionalstudyisalreadyunderwaytounderstandthe complexitiesofthissiteinmoredetail,lookatpotentialoptionsandto findasolutionthatwillbalancetheneedsofallparties.

NextSteps

Deliveryofsolutionswhichmeettheneedsofallstakeholderswillbea challenge;particularlygiventheunfavourableconditionofthehabitats withinChichesterHarbour,whichisinpartduetoexistingdefences causingcoastalsqueeze,meaningfrontlinedefenceapproachesto floodanderosionprotectionmaynolongerbeconsentablewhere theyarenotprotectingpropertyorinfrastructure.

AhabitatrestorationschemeforNorthneyhasbeenproposedinthe Strategy’sshorttermactionplantofollowthestudy.Subjectto securingfunding,thiswillstartwithafeasibilitystudytoappraise appropriatecoastalmanagementoptionsandalignmentswhich providetheleastdamagingimpactonthenaturalenvironment.

ODU4:ChichesterRoadtoMillRytheJuniorSchool

Overview

ODU4extendsfromtheNorthneyFarmboundaryatChichesterRoadsouthto MillRytheJuniorschool.Thisfrontagecomprisesamixofagriculturalland, interspersedwithsmallnumbersofresidentialproperties,aholidaycaravan parkandaworkingmarina.Twoareasofformercoastallandfillarealso locatedhere.

Defences

Someofthefrontageisundefended,butwheredefencesexist,theyareadhoc embankmentsandquaywalls,privatelyowned.Defencesaremaintained privatelyorbytheEnvironmentAgency.Residuallivesareshort,typically between10and15years,withsomelocallylessthan10yearsandsoare susceptibletofailureintheshortterm.

Environment

ThefrontagehassignificantenvironmentaldesignationsintheHarbour, including,SSSI,Ramsar,SPAandSAC.Onland,VernerCommonis designatedSSSI,RamsarandSPAandGutnerPointLocalNatureReserve, locatedinthesoutheastofthefrontage,isdesignatedasSSSI,Ramsar,SPA andSAC.SectionsofthisunitalsofallwithintheChichesterHarbour NationalLandscape.Thisfrontageincludeslandthatisimportantforbirds, havinganumberofcoreandprimarysupportareasidentifiedintheSolent WadersandBrentGooseStrategy.

ShorelineManagementPlanPolicy

HoldtheLine,butnopublicfundingavailableforprivatedefencesforthe next100years.Duetothesmallnumberofpropertiesatriskhere,thereis unlikelytobeanycentralfundingavailabletoprogressthispolicyintothe future.

ODU4location

Saltmarshes

Risk

Themainriskalongthisfrontageisfromtidalflooding,wherethereisacontinuousfloodcellalongthecoast.Land, however,risesquitequicklyinland,sofloodriskisrelativelylownow,butwillincreaseinthefuture,especiallyat VernerCommon.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

StrategicIntent

Thestrategicintentforthisunitisadaptationofassetstobecome moreresilienttoandadjusttoclimatechangeimpactsinthe futureasfloodriskislow.Iflandownerswishtomaintain/replace (andfund)theirdefencestoreducerisktoexistingresidentialand commercialpropertiesinthefuturebutalsopreventformer landfillfromeroding/leachingintotheHarbour,theywillneedto obtaintherelevantlicencesandconsentsfirst.Itisworthnoting thatthestrategicintentdeviatesawayfromtheSMPpolicytoHold theLinefor100years.

NextSteps

Noneidentifiedforthisfrontageintheshort-term,otherthan ongoingconversationswithcommunitiesinrelationtolevels ofriskandwhattodointheeventofaflood.

Overview

ODU5islocatedbetweenMillRytheJuniorSchoolandSalternsLane.This frontagehasbeensplitintothreesubunits(ODU5A,5Band5C)toreflectthe changesinlanduseandriskwithinthisunit.ODU5AincorporatestheMill RytheHolidayVillageborderedbyagriculturalland.ODU5Bispredominately agriculturalfarmlandalongsideTournerburyGolfCourse.TothesouthODU5C stretchesfromTournerburyWoodsEstatetoSalternsLaneandincludes TournerburyWoodsEstate,andadhocresidentialandcommercialproperties. Defences Defencesconsistofavarietyofembankmentandrevetmentstructures.InODU 5A,aroundtheMillRytheHolidayVillage,defencesareprivatelyownedbut maintainedbytheEnvironmentAgencyandhaveresiduallivesofbetween10 and15years.Elsewheretheresiduallivesoftheseprivatelyownedand maintaineddefencesarelessthan10yearsandinlocalisedareasarealready failing.TheexceptionbeingtherockrevetmentsouthofTounerburyGolf Coursewhichhasaresiduallifeofbetween15and20years.

Environment

Thefrontageiscoveredbysignificantenvironmentaldesignations,bothon landandintheHarbourandfallswithintheChichesterHarbourNational Landscape.AgriculturallandinODU5BandTournerburyWoodsEstatein ODU5CaredesignatedasSSSI,RamsarandSPA,whilethefrontingintertidal areasareSSSI,Ramsar,SPAandSAC.Anareaofformercoastallandfillisalso locatedinthefarsouthoftheunit,andTournerBuryScheduledMonument, theremainsofanIronAgeplateauhillfort,alsotothesouth,isatincreasing tidalfloodriskovertime.

ShorelineManagementPlanPolicy

HoldtheLine,butnopublicfundingavailableforprivatedefencesforthe next100years.

ODU5A,5Band5Clocation ODU5A Embankment

ODU5A

ODU5B

ODU5C

Risk

Riskhereisfromtidalflooding,wherethefloodextentreachesasfarasMillRythevillage.Here,over200 propertiesaswellasMillRytheJuniorSchoolareattidalfloodriskoverthenext100years,withoutdefencesin place.AlthoughtheGolfCourseandassociatedassetsareonhigherland,sonotatrisk,tidalfloodriskissignificant inthelowerlyingareas.IncontrastODU5Cisonhigherland,sofloodanderosionrisktoadhocpropertiesand TournerburyWoodsEstateislow.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

OverallStrategicOption Sustain1.33%AEPwith managedrealignment

defencesalongthecentralsectiontoallowforhabitatcreationand naturalevolutionoftheshoreline(ODU5B),andinthesouth,prevent formerlandfillfromeroding/leachingintotheHarbour(ODU5C).

Notonlydoesthisprovidefloodriskprotectiontopropertiesandthe schoolinthenorth,butitalsoprotectsformercoastallandfillwhilst makingspacefornaturewhereviabletodoso,tomeettheneedsof ChichesterHarbourtocreateamosaicofnewhabitats.Thiswillrequire constructionofnewmoresustainabledefencesinphasesandablended managementapproachinclosecollaborationwithallpartners.Ifthe landfillisfoundnottobeharmfultotheenvironment,then opportunitiestosetbackdefencesshouldbeinvestigatedhere.

NextSteps

Anadditionalstudyisalreadyunderwaytounderstandthecomplexitiesof theTournerburyFarm(ODU5B)siteinmoredetailtolookatpotential optionsandtofindasolutionthatwillbalancetheneedsofallparties.A habitatrestorationschemeforTournerburyhasbeenproposedinthe Strategy’sshorttermactionplantofollowthestudy.Subjecttosecuring funding,thiswillstartwithafeasibilitystudytoappraiseappropriatecoastal managementoptionsandalignmentswhichprovidetheleastdamaging impactonthenaturalenvironment.

ODU6: Salterns Laneto Wilsons Boat Yard

Overview

ODU6islocatedbetweenSalternsLaneintheWestandWilsonsBoatYardin theEast.Residentialpropertiesandaccompanyingadhocprivatelyowned defencescharacterisethisshortunit.

Defences

Residuallivesofdefencesareunknownduetoinaccessibilityalongthis frontage.InlandrelativelandlevelsarehighcomparedtoadjacentODUs.

Environment

TheintertidalHarbourareaborderingthisfrontageisenvironmentally designatedasSSSI,Ramsar,SPA,SACandfallswithintheChichesterHarbour NationalLandscape.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years.

ODU6

WilsonsBoat Yard

Risk

Floodanderosionrisksarelowuntilthelongerterm,when99propertiesareshowntobeatriskoftidalflooding withnodefencespresent.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

MaintainthenImprove0.5% AEPfrom2075

residentialproperties,bymaximisingthelifeofexistingdefencesby defenceownersintheshortandmediumterm,subjectto obtainingtherelevantlicencesandconsents,beforeconstructing newdefencesinthelongtermtoreducerisktoproperties.Where landownersarenolongerabletomaintaintheirdefences,or fundingforaschemeisnotfound,adaptationwillneedtobe exploredasacommunity,toadjusttotherealityoffuturecoastal floodanderosionrisk.

NextSteps

Noneidentifiedforthisfrontageintheshort-term,otherthanongoing conversationswithcommunitiesinrelationtolevelsofriskandwhat todointheeventofaflood.

ODU7:WilsonsBoatYardtoFisheryCreek

Overview

ODU7islocatedbetweenWilsonsBoatYardandFisheryCreek.Thefrontage comprisesalargeextentofresidentialpropertiesandavarietyofcommercial landuses,includingWilson’sBoatYard,MenghamRytheSailingClubanda numberofholiday/touringparks.

Environment

TheintertidalHarbourareaborderingthisfrontageisenvironmentally designatedasSSSI,Ramsar,SPA,SACand,alongwiththelandwardeastern fringe,fallswithintheChichesterHarbourNationalLandscape.Twoareasof formerlandfillarealsolocatedalongthemorevulnerablesectionoffrontage, whereriskoferosionisprobableinthenearfuture.

Defences

Defencesvaryalongthefrontage.Alongthenorth-easternsectionconcrete revetmentsandquaysareadjacenttotheEnvironmentAgency’sSelsmore andMenghamCoastalDefenceschemewhichconsistsofrockrevetment andwascompletedin2012.Defencesalongthissectionareprivately ownedbutmaintainedbytheEnvironmentAgencyandhaveresiduallives oftypically10to20plusyears.

Tothesouth,thereisashortsectionofrockfilledgabionbasketswhichare ingoodcondition,againprivatelyowned,butmaintainedbythe EnvironmentAgency.However,theremainingfrontageextendingtowards FisheryCreekconsistsofanaturalearthvergewithnoharddefences.The vergeisinpoorcondition,hasashortresiduallifeoflessthan10yearsand isactivelyerodinginplaces.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years.

WilsonsBoatYard

Risk

Themainriskalongthenorth-eastfrontageisfromtidalflooding.Herethereisacontinuousfloodcellwhere approximately302propertiesareatriskoverthenext100years,withoutdefencesinplace.Alongthesouth-east coastthemainriskisfromerosionwherethereisformercoastallandfillatrisk.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

£10,888,000 PresentValue

StrategicIntent

Thestrategicintentfortheunitistoreducefloodanderosionrisk topropertiesoverthenext100yearsbutalsopreventformer landfillfromeroding/leachingintotheHarbour.Thiswillrequire constructionofnewdefencesinaphasedapproachovertime.

NextSteps

AFloodandCoastalErosionRiskManagementSchemeforthe frontagehasbeenproposedintheStrategy’sshorttermactionplan. Subjecttosecuringfunding,thiswillstartwithafeasibilitystudyto appraiseappropriatecoastalmanagementoptionsandalignments alongthisfrontage.

ODU8:Eastoke

Overview

ODU8includestheEastokepeninsula,whichhasbeensplitintonorthern andsouthernsections.

Thisunitcoversboththeshelteredharbourenvironmentalongthenorthern shorealongwiththehighlydynamicsouthernopencoastfrontage,bothof whicharefrontedbysignificantenvironmentaldesignations.Thisresultsin thecomplexchallengeoftidallydrivenfloodriskintheharbourcoupledwith highenergywaveovertoppinganderosionriskalongtheopencoast.

Theareaisheavilyurbanisedandalsocontainsseveralholidayparks,aRNLI station,sailingclub,marinaandnaturereserve.Thesouthernfrontageiswell usedbyresidentsandtourists,soaccesstothebeachisimportant,andthe draftHavantBoroughCouncilLocalPlanidentifiesopportunitiesfor regenerationalongsomepartsofthesoutherncoastline.

Environment

TheintertidalHarbourareatothenorthandeastofthisfrontageis environmentallydesignatedasSSSI,Ramsar,SPA,SACand,alongwiththe northernlandwardfringe,spitandSandyPointLocalNatureReserve,falls withintheChichesterHarbourNationalLandscape.ThenatureReserveis alsoenvironmentallydesignatedasSSSI,RamsarandSPA,whiletheopen coastsubtidalareaisadesignatedSAC.

CoastalProcesses

HaylingIslandisunusualcomparedtootherlocationsinthatitsbeachesare susceptibletobi-modalwaveconditions,wherelongperiodswellwaves refractaroundtheIsleofWight,coincidingwithlocalstormconditions.This resultsinveryenergeticwaveconditionsthatcanbeextremelydamagingto thecoastline.

Defences

Thereareawidevarietyofdefenceshere,includingseawalls,sheetpiling, rockrevetments(aspartoftheEastokeSchemecompletedin2005)and groynes.Themajorityofdefencesalongthenorthofthefrontagehave residuallivesbetween10and20yearsandareprivatelyownedand maintained,withtheexceptionofdefencesimmediatelywestofSparkes MarinawhicharemaintainedbytheEnvironmentAgency.Asyoumore roundtothesouthofthefrontage,rockrevetementsareingoodcondition andareownedandmaintainedbyHavantBoroughCouncil.Thebeachitself isavitalcomponentofthecoastaldefenceandiscurrentlymaintainedby HavantBoroughCouncilthroughbeachnourishmentandbeachrecycling whichtakesplaceatregularintervals.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years.

Risk

Therisksherearepredominantlyfromwaveovertoppingandcoastalerosioninthesouthandtidalfloodingfromthe north.Thesouthernfrontagehasalonghistoryofhighenergywaveaction,whichresultsinsignificantbeach drawdown,cutbackandlossofmaterial.Thisisduetobi-modalwaveconditions,whenlongperiodswellwavesrefract aroundtheIsleofWight,coincidingwithlocalstormconditions.Theresultishighlyenergeticwaveconditionsthatcan beverydamagingtothecoastline.

InthefuturethereisariskofjoinedupfloodingacrosstheentireEastokepeninsularandassuchtheunithastobe treatedasonecompletefloodcell.Thereareupto1,253propertiesatriskoferosionand1,472propertiesatriskof floodingoverthenext100yearswithoutdefences.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

Donothing damages

£286,875,000 PresentValue

Thestrategicintentintheveryshorttermistorenewtheexisting BeachManagementPlanandimplementthisoverthenext5years (2024-2029).However,itisrecognisedthatbeyondthisamore strategicsuiteofmeasureswillberequiredtoprotecttheentire peninsula.Thiswillinvolvethedevelopmentofasinglepeninsular wideschemeunderonebusinesscasewithaprogrammeofworksto constructnewdefencessuchasfloodwallsalongthenorthernfrontage andthebuildingofanewrockrevetmentalongpartsofthesouthern frontage;coupledwithnewrockgroynes.Ontopofthisongoingbeach managementwillberequiredtomaintainahealthyandrobustbeach toreducetheimpactsofhighenergywaves.

NextSteps

FurtherstudiesintoBi-modalwavesarealreadyunderwayto understandtherisktothiscoastalunitwhichwillinformfuture managementofthebeach.AFloodandCoastalErosionRisk ManagementSchemeforEastokehasbeenproposedintheStrategy’s shorttermactionplan.Subjecttosecuringfunding,thiswillstartwith afeasibilitystudytolookatandappraiseappropriatecoastal managementoptionsforthepeninsular.

ODU9:EastokeCornertoInnontheBeach

Overview

ODU9stretchesalongtheopencoastbetweenEastokeCornerandtheInnon theBeach.

Thebeachfrontageiswellusedbyresidentsandtourists,andincludescar parks,beachhuts,roadsandrecreationareas,andisbackedbyhigh concentrationsofresidential/commercialareas.

Environment

LandwardareasinthewestareenvironmentallydesignatedasaSSSIandthe subtidalareaofthewholeODUiswithintheSolentMaritimeSAC.

Defences

ThebeachformsthemaindefenceandiscurrentlymaintainedbyHavant BoroughCouncilthroughbeachnourishmentandbeachrecyclingwhichtakes placeatregularintervals.TheonlyotherdefencesareHavantBoroughCouncil ownedandmaintainedtimberrevetmentsandgroynestotheeastandthe privatelyownedandmaintainedconcreteseawallinfrontoftheInnonthe Beach.TheInnontheBeachactsasabeachcontrolstructure,effectively keepingthebeachinplace.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years.

Eastoke Corner

ODU9

Risk

Riskhereispredominantlyfromwaveovertoppingandcoastalerosionasaresultofbi-modalwaveconditions, whenlongperiodswellwavesrefractaroundtheIsleofWight,coincidingwithlocalstormconditions.Theresultis highlyenergeticwaveconditionsthatcanbeverydamagingtothecoastline.

Althoughpropertiesaresetbackfromthebeach,itisexpectedthatupto147propertieswillbeatriskoferosion and121fromcoastalfloodingoverthenext100yearswithoutdefencesorabeachinplace.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

Sustain0.5%AEPMaintain terminalstructure

defencessetatthebackofthebeachwouldberequiredtoprotect thecommunityintothefutureandtomaintainanadaptivecontrol structureinthevicinityofInnontheBeachbecauseitplaysakey roleinthebeachmanagementherepromotingsediment accumulationtokeepthebeachinplacetotheeast.Thisisan importantfeatureforlongshoresedimenttransportandretaining thebeachprofileforuseinwiderbeachmanagementacrossthis unitandODU8.

NextSteps

FurtherstudiesintoBi-modalwavesarealreadyunderwayto understandtherisktothiscoastalunitwhichwillinformfuturebeach management.

ODU10:InnontheBeachtoNorthShoreRoad

Overview

ODU10extendsbetweentheInnontheBeachandNorthShoreRoadandhas beensplitintonorthernandsouthernsections.Thehighenergyopencoastto thesouthisbackedbynaturalduneandmaritimegrasslandareasandinplacesis anaccretingcoastline.Thewesternandnorthernpartoftheunitcoversthe harbourentranceandshelteredcoastlinetothenorth.

Thelarge,undefendedopencoastsouthernfrontageincludesWestBeach,the naturalduneareaofSinahCommon,privategolfcourses,asailingclubandcar parks.TheDraftHBCLocalPlanidentifiedtheopportunityforregenerationat WestBeachnotingtheabundanceofenvironmentaldesignationsinthelocality.

Thenorthernharbourfrontageincludesbusinesses,theferrycrossingtoEastney, aboatyard,slipways,FerryRoad,theresidentialcommunityattheKench,the Kenchnaturereserveandaholidaycomplex.

Environment

TheopencoasttothesouthisenvironmentallydesignatedasaSAC,whilethe naturalduneandmaritimegrasslandonSinnahCommonisdesignatedSSSI.The intertidalHarbourareaborderingthisfrontageisenvironmentallydesignatedas SSSI,Ramsar,SPAandSAC,andthereisaLocalNatureReserveattheKench.

Defences

Thesouthernunitisstrategicallyreliantontheimplementationofnew adaptablecontrolstructuresinthevicinityofInnontheBeachtocontrolthe movementofsedimentandallowbeachmanagementacrosstheentireopen coastofHaylingIsland.Currently,theshortsectionoftimberrevetmentand rocktothewestofInnontheBeachismonitoredbyHavantBoroughCouncil whiletheremainingfrontagearoundGunnerPointisundefended. Ad-hocdefencesalongthenorthernfrontageareprivatelyownedand maintained,mainlyconsistofconcretewalls,blockworkandembankments andhaveresiduallivesofbetween10and20years.Thecommunityatthe Kenchprivatelyownsandmaintainstheirowndefencesandareactively planningadapttoclimatechangerisksinthefuture.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years,withanintenttoallownatural processestocontinuearoundGunnerPoint.

WestBeach

Risk

Theriskinthesouthisprimarilyfromwaveovertoppingandcoastalerosion,butareasofSinahCommonalso naturallyaccretearoundGunnerPoint.Thereisariskoftidalfloodingfromtheharbouralongthenorthern frontage.Thereareexpectedtobe53propertiesatriskoferosionand95atriskoffloodingoverthenext100years ifundefended,ofwhichmostaresituatedintheNorthoftheODU.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

Throughouttheunit,theintentisforadaptationofassetsto becomemoreresilienttoclimatechangeimpactsinthefuture,ina managedway,alongsidenaturalevolutionoftheopencoast shorelinetoimprovepublicopenspaceandenhancethenatural environment.Acollaborativeapproachbetweenalllandowners andstakeholderswillberequiredtobalancethecomplexneedsof thecoastlinehere.Iflandownersdowishtocontinuetomaintain (andfund)theirdefencesinthefuture,theywillneedtoobtainthe relevantlicencesandconsentsfirst.

NextSteps

Aholisticenvironmentalmanagementplanforthisareaasidentifiedin theStrategy’sshorttermactionplanisunderway.Dialoguewithkey stakeholdersandlandownerswillcontinueregardingthemanagement optionsforthisfrontage.

ODU11:North ShoreRoad

ODU11:NorthShoreRoad

Overview

ODU11extendsalongtheresidentialNorthShoreRoadfrontage.

Defences

Residentialpropertiesandaccompanyingadhocmixofprivatelyownedandmaintaineddefencescharacterisethisunit.Defencesvaryfromconcretewallsto embankmentstobreezeblockstructures.Consequently,defencelifeandconditionvaryfromdefencetodefence,butgenerallyhaveresiduallivesofbetween10 and20years.

Environment

TheintertidalHarbourareaborderingthisrelativelyshelteredfrontageisenvironmentallydesignatedasSSSI,Ramsar,SPAandSAC.

ShorelineManagementPlanPolicy

Holdthelineforthenext100years.

Risk

FloodriskhereisfromtidalinundationinthewestoftheunitinfrontofSinahLane,anderosiontotheeastinfront ofNorthShoreRoad.Withnodefences,thereisariskoffloodingandcoastalerosionintheshorttermonthewest side,howevererosionriskontheeastsideisnotpredictedtooccuruntilthemediumterm.

Duringlargerreturnperiodseventsinthefuture,withoutdefences,thereispotentialforthisfloodareainthewest, tomergewiththefloodcellfromthesouth,whereupto83propertiesareshowntobeatriskoverthenext100 years.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

Donothing damages

£3,471,000 Presentvalue

StrategicIntent

TheStrategicintenthereistomaintainfloodanderosion protectiontoresidents,byconstructingnewdefencesinstages, dependantonrisk.Wherelandownersarenolongerableto maintaintheirdefences,orfundingforaschemeisnotfound, adaptationwillneedtobeexploredasacommunity,toadjustto therealityoffuturecoastalfloodanderosionrisk.

NextSteps

Noneidentifiedforthisfrontageintheshort-term,otherthanongoing conversationswithcommunitiesinrelationtolevelsofriskandwhat todointheeventofaflood.

ODU12:NorthShoreRoadtoNewtown

Overview

ODU12extendsfromNorthShoreRoadtoNewtown.Thisunitisasmall sectionofundevelopedandundefendedcoast,characterisedbyprivately ownedagriculturallandimportantforbirds,beingidentifiedasacoreareain theSolentWadersandBrentGooseStrategy.

ThewidelyusedHaylingBillyTrailandHaylingBillyLocalNatureReserveare setbackfromthecoastinthislocation.ACoastalChangeManagementArea hasbeendesignatedhere,throughtheHavantBoroughCouncilLocalPlan,to preventinappropriatedevelopmentfromtakingplacethatmaybeatriskfrom futureerosion.

Environment

Theintertidalareaadjacenttothisfrontageisheavilyenvironmentally designatedasaSSSI,Ramsar,SPAandSAC.

ShorelineManagementPlanPolicy

NoActiveInterventionacrossthisunitforthenext100years.

ODU12

ODU12location

ODU12 Eroding cliffs

Risk

Duetothetopography,erosionisthemainrisk,however,therearenoassetsatriskalongthisfrontage.TheDo NothingdamagesinthisODUrelatetoagriculturalandrecreationallosses.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

Donothing damages

£90,000 PresentValue

StrategicIntent

ThestrategicintentinthisODUistomakespacefornatureby allowingthecoasttocontinuetoevolvenaturally,erodingto providesedimenttotheharbourandbeaches.

NextSteps

Noneidentifiedforthisfrontageintheshort-term.

ODU13:Newtown

Overview

ODU13encompassesthecoastlineatNewtown.

Defences

DefencesconsistofanArmorlocembankmentwithalocalisedharddefence aroundanoutfall.Althoughthedefencesareprivatelyowned,theyare maintainedbytheEnvironmentAgencyandhaveresiduallivesofbetween15 and20years.Withmaintenance,theexistingdefencesareexpectedto continuetoprovideprotectionintothemediumterm.

Environment

Liketherestoftheisland’swestcoast,theintertidalareaadjacenttothis frontageisheavilyenvironmentallydesignatedasaSSSI,Ramsar,SPAandSAC. TheNewtowncoastalfrontageitselfconsistsofafield,whichisenvironmentally designatedasSSSI,RamsarandSPA,borderedbythewidelyusedHaylingBilly TrailandHaylingBillyLocalNatureReservetotheeast,beforeyoureachthe communityofNewtown.

ShorelineManagementPlanPolicy

DuetotheincreasedfloodriskatNewtown,this frontagehasalocalisedHoldTheLinepolicyforthe next100years.

ODU13

ODU13 outfall

Risk

TheNewtownfrontageencompassesalocalisedpocketoftidalfloodriskwhichextendstothecommunityof Newtown.Withoutdefencesitisexpectedthattherewillbeupto80propertiesinNewtownatriskoffromtidal floodingoverthenext100years.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

OverallStrategicOption Maintainthensustain0.5%AEPfrom 2045

StrategicIntent

TheStrategicintenthereistocontinuetoreducerisktocurrent residentialproperties,communityandbusinessesinNewtown,by maintainingexistingdefencesintheshortterm,subjectto obtainingtherelevantlicencesandconsents,beforeconstructing newdefencesinthemediumtermtoreducerisktoproperties.

NextSteps

Noneidentifiedforthisfrontageintheshort-term,otherthanongoing conversationswithcommunitiesinrelationtolevelsofriskandwhat todointheeventofaflood.

ODU14:NewtowntoStoke

Overview

ODU14extendsalongthelargelyundevelopedandundefendedfrontagefrom NewtowntoStoke.Thisrelativelylongunitcomprisesmainlyprivate,or HampshireCountyCouncilownedagriculturallandadjacenttothecoast.

Defences

Thisunitismainlyundefended,butwhereadhocembankmentsand revetmentsdoexist,thesehavearesiduallifeoflessthan10years,andin someplaceshasalreadyfailed.Thesedefencesarecurrentlymaintainedby privatelandownersorHampshireCountyCouncil.

Infrastructure

TheHaylingBillyTrailisanimportantpublicfootpathandNationalCycleRoute whichiswidelyused,andwhereclosetotheshorelineisatriskoferosion.The HaylingBillyTrail,alsodesignatedasaLocalNatureReserve,isacknowledged asacriticalpieceofinfrastructureintheDraftHavantBoroughCouncilLocal Planforsustainabletransport.

Environment

TheLangstoneHarbourintertidalareaadjacenttothisfrontageisheavily environmentallydesignatedasaSSSI,Ramsar,SPA,SACandisincludedasan importantSolentWaderandBrentGooseSiteandbirdrefugeintheDraftLocal Plan.

ShorelineManagementPlanPolicy

NoActiveInterventionforthenext100years.

ODU14 cliff erosion

ODU14location

ODU14

Risk

Erosionisthemainrisk,howevertherearepocketsoffloodriskinthecentreandfarnorthofthefrontage.Four propertiesareatfloodriskoverthenext100yearswithoutdefencesinplace,alongwithsmallsectionsofWest Lane,akeyaccessroutetothesouthoftheisland,andtheHaylingBillyTrail.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

OverallStrategicOption

Donothing

toallownaturalprocessestocontinuetomakespacefornature. PotentialrollbackoftheHaylingBillyTrailwillneedtobe consideredinareasatrisk,tomaintaintheaccessroutebecause buildingnewdefencestoprotecttheTrailinitscurrentlocationis unlikelytobeconsentablebyregulators.Adaptationwillneedto beexploredforthosefewpropertiesatfloodriskinthelonger term,andlocalisedfloodprotectiontoWestLaneshouldbe considereddependantonriskinthefuture.

NextSteps

Noneidentifiedforthisfrontageintheshort-term,otherthanongoing conversationswithcommunitiesinrelationtolevelsofriskandwhat todointheeventofaflood.

ODU15:StoketoLangstone BridgeCarpark

ODU15:StoketoLangstoneBridgeCarpark

Overview

ODU15extendsfromStoketotheLangstonebridgecarpark.Thisunitis complexgiventhetidalfloodrisk,andvaryinglanduses.Thefrontageincludes agriculturalland,theOysterBeds,formerlandfillsites,thewidelyusedHayling BillyTrailwhichisaNationalCycleRoute,theA3023mainaccessroadonto HaylingandresidentialpropertiesatStoke.

Defences

Defencesconsistofamixofrevetments,embankmentsandgabionwithtypical residuallivesofbetween10and15years,althoughlocallysomesectionsareless than10years.Thesedefencesarecurrentlyownedandmaintainedby HampshireCountyCouncilorHavantBoroughCouncil,withtheexceptionofa smallsectionofrevetmenttothesouthoftheunitwhichisownedbyHampshire CountyCouncilbutmaintainedbytheEnvironmentAgency.

Environment

Thefrontageiscoveredbysignificantenvironmentaldesignations,including SSSI,Ramsar,SPAandSACinintertidalareasandtheOysterBeds,aswellas SSSI,RamsarandSPAontheformerlandfillsites.Thesiteisalsoidentifiedas animportantSolentWaderandBrentGooseSiteintheHavantBorough CouncilDraftLocalPlan.Therearetwolocalnaturereserveshere,TheWest HaylingLNRwhichextendsovertheformerOysterbedsandmanagedbythe RSPB,andtheHaylingBillyLNR.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years,butwithfurtherdetailedstudiesto considerManagedRealignmentatWestNorthneyandRegulatedTidal ExchangeatStoke.

ODU15location

Oysterbeds

Risk

Erosionriskislow,althoughtheOysterBeds,formerlandfillsitesandpartsoftheHaylingBillyTrailmaybeatriskin thefuture.BothresidentialpropertiesandtheA3023however,areatriskoftidalfloodingwherethereisacoherent floodcellacrossthewholefrontage.Overthenext100yearsitisexpectedthattherewillbeupto268properties andsignificantsectionsoftheA3023atriskoftidalfloodingacrosstheunitwithoutprotection.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

TODAY 100YEARS

TheStrategicintentfortheunitistoconstructnewset-back defencesinaphasedapproach,tomaintaintheviabilityofthe A3023,theHaylingBillyTrailandthecommunityatStoke,protect formerlandfill,whilstmakingspacefornaturewhereviabletodo so.Intheareaofthehistoriclandfill,theexistingfrontlinedefences wouldbemaintainedtopreventerosionuntilfurtherstudiesare completed.Ifformerlandfillisfoundtobeinert,theoptioncould considerremediationandsetbackdefences.

NextSteps

AFloodandCoastalErosionRiskManagementStudyfortheA3023has beenproposedintheStrategy’sshorttermactionplan,subjectto securingfunding.

ODU16:LangstoneBridgeCarparktoLangstoneBridge

Overview

ODU16extendsfromtheLangstoneBridgecarparktoLangstoneBridge, withHaylingIsland’smainaccessroad,theA3023,runningcloselyalongside. ThemainrisktotheA3203,identifiedasacriticalpieceofinfrastructurein HavantBoroughCouncil’sdraftlocalplan,isfromtidalflooding.

Defences

Thereisamixofdefencesalongthisshortunit,includingsheetpilinganda revetment,ownedandmaintainedbyHampshireCountyCouncil.Residual lifeofthesedefencesisbetween10and20years.

Environment

TheHarbourintertidalareaadjacenttothisfrontageisheavily environmentallydesignatedasaSSSI,Ramsar,SPAandSAC.

ShorelineManagementPlanPolicy

HoldtheLineforthenext100years.

Lookingbackatthe OysterbedsfromODU16

ODU16location

ODU16

Risk

Themainriskhereisfromtidalflooding.Withoutdefencesinplace,thefloodcellcouldmergewithadjacentflood cellstotheeast(inODU1)andwest(inODU15)duringlargerreturnperiodevents.Inthisscenario,safeaccessand egressontoandofftheislandwouldbeseverelycompromised.

Themapsbelowshowthemodelledextentanddepthsofanextremetidalfloodevent(1in200year,0.5%annual probability),withoutanydefences,todayandin100years,allowingforsealevelrise.

Erosionrisk

Numberofpropertiesatrisk,withnodefences

Tidalfloodrisk

Numberofpropertiesatrisk,withnodefences

TODAY 100YEARS

StrategicIntent

TheStrategicintentfortheunitistoprotectandmaintainthe viabilityoftheA3023intothefuture,ascriticalroadinfrastructure ontheisland.

NextSteps

AFloodandCoastalErosionRiskManagementStudyfortheA3023has beenproposedintheStrategy’sshorttermactionplan,subjectto securingfunding.

*PropertyResilience …modificationsaddedtoabuildingto loweritsfloodrisk.Itcanreducethe riskofwatergettingintopropertiesand speeduprecoveryafteraflood.

Chapter6: Short-termactionplan

StrategyLeadingOptionCostsandBenefits

Thisreportoutlinedtheprocessbywhichtheoverallleadingoptionshave beendevelopedthroughamulti-criteriaappraisal.Theappraisalprocess consideredthetechnical,economic,environmentalandsocialaspectsofeach option.Thetablebelowpresentsasummaryoftheeconomiccostsand benefitsforeachoftheoverallleadingoptionsforeachODU.

•Thereisnoguaranteethatanyoftheseleadingoptionswillbe progressed,it’salldowntofunding.

•Significantfundingfromavarietyofsourceswillbeneededtoprogress theleadingoptions.

•Publicfundsforcoastalmanagementarenotwidelyavailableandkey criteriahavetobemetinordertoapplyforfunds,butitmaybepossible tosecuresomefundsforkeyareassuchasEastoke,Selsmoreand Mengham.

•Wewillworktodevelopbusinesscasestoprogressschemesifthereis fundingandifit’sinthepublicinterest(technical,environmental,social andeconomicsolution).

ShortTermActionPlan

TheStrategyhasidentifiedtheneedforanumberofstudies,projectsandschemesoverthenext10yearsiffundingandapprovalscanbesecured.Theseinclude habitatrestoration,beachmanagement,coastaldefenceandadaptationschemes.Aguideshowingtherelevantlocationsisshownbelow,togetherwiththe recommendedtimescalepresentedoverleaf,alongwithanticipatedcostsandpotentialfundingsources.

ShortTermActionPlan

IndicativeCostsandFunding

TheStrategyhasidentifiedhighlevelindicativecoststodeliverthe short-termactionplan.Thesecostsweredevelopedasasnapshot intime.Giventhecurrenteconomicsituation,thesecostswill needtobereassessedattheappropriatetime. Potentialfunding

SolentDynamicCoastProjectupdatetoupdate coastalsqueezelossesusingUKCP18sealevel riseprojections

SolentandSouthDownsHabitatCreationand RestorationProgrammeCoastalGrazingMarsh Studytoidentifysuitablecompensatorycoastal grazingmarshsites.

Whatyoucandotoprotectyourself?

Protectyourselffromfutureflooding

Ifyouliveinanareathatisknowntobeatriskorhasbeenfloodedinthepast, makesurethatyouknowwhattoinaflood.Ifyouaren’tsureifyouliveina floodriskarea,youcanchecktheGovernments‘Checkforflooding’website.

Youcanmakeyourpropertyresilienttofloodwaterwhichwillreducethe damagecausedbyflooding,resultinginlesstimeoutofyourhomeorbusiness andcheaperrepairs.Ifyouareahomeowner,itisyourresponsibilitytoprotect yourpropertyfromflooding.

Thefollowingwebsiteshaveinformationwhichwillhelpyouprepareforand protectyourselffromflooding.

•EnvironmentAgencyplus'howtoplanaheadforflooding'

•CitizensAdviceBureau

•MetOfficeforuptodateweatherforecasts.

•TheBluePagesdirectoryhasvarioussuggestionsforproductsandservices thatareavailabletohelpprotectyourproperty.

•SignuptotheEnvironmentAgency’sFloodlineWarningsDirect.

CompetentstaffatHavantBoroughCouncilarepreparedtohandleany significantemergency.Theywillcoordinatethecouncil'seffortstomitigatethe incident'simpactontheborough'sresidents,businesses.Formoreinformation goto:www.havant.gov.uk/emergency-advice

Considersettingupacommunityfloodactiongroup

Afloodactiongroupisavoluntarygroupofresidentswhoworkonbehalfof thecommunitytohelptoraiseawarenessoflocalfloodriskandreducethe impactoffloodevents.

Thegroupwouldhavealocalfocusandcanhaveavarietyofvaluableroles suchas:

•Monitorlocalconditionse.g.communityvolunteerskeepinganeyeoutfor blockeddrains.

•Developandreviewacommunityfloodplan.

•Prepareforandtakeactionduringafloodevente.g.helpingtoinstall PropertyLevelResilience.

•Identifykeyfloodingissueswithinthecommunity.

•Buildrelationshipsandlinesofcommunicationwithauthorities.

•LobbyingofdecisionmakersandcommentingonGovernment consultations.

•Helptoinfluencethedevelopmentoffuturefloodschemestomanageflood risk.

Formoreinformationonfloodactiongroupsandhowtosetupone,thereisa wealthofinformationonlineviatheEnvironmentAgency,TheFloodHuband theNationalFloodForum.AlternativelyspeaktoCoastalPartners.