





ODU9stretchesalongtheopencoastbetweenEastokeCornerandtheInnon theBeach.
Thebeachfrontageiswellusedbyresidentsandtourists,andincludescar parks,beachhuts,roadsandrecreationareas,andisbackedbyhigh concentrationsofresidential/commercialareas.
LandwardareasinthewestareenvironmentallydesignatedasaSSSIandthe subtidalareaofthewholeODUiswithintheSolentMaritimeSAC.
ThebeachformsthemaindefenceandiscurrentlymaintainedbyHavant BoroughCouncilthroughbeachnourishmentandbeachrecyclingwhichtakes placeatregularintervals.TheonlyotherdefencesareHavantBoroughCouncil ownedandmaintainedtimberrevetmentsandgroynestotheeastandthe privatelyownedandmaintainedconcreteseawallinfrontoftheInnonthe Beach.TheInnontheBeachactsasabeachcontrolstructure,effectively keepingthebeachinplace.
HoldtheLineforthenext100years.
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.