climate change impact assessment 2010 · sca climate change impact assessment 2010 2 executive...
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Sydney Catchment Authority
Climate Change Impact Assessment2010
Blue Mountains Catchments
Cooma
Sydney Catchment Authority Drinking water catchments
Pumping station
Canals and pipelines
Prospect WaterFiltration Plant
SCA’s drinking water catchments
Uppe
r Can
al
Pipelines
Braidwood
Canberra
Shoa
lhav
en River
Goulburn
Nowra
Wollongong
Lithgow
Sydney
Wollondilly River
Bendeela PondageLake Yarrunga
Nattai River
Nepean River Woro
nora River
Haw
kesb
ury R
iverCoxs River
ProspectReservoir
WarragambaDam
WoronoraDam
TallowaDam
Fitzroy FallsReservoir
WoodfordDam
Greaves CreekDam
MedlowDam
CascadeDams
CordeauxDam
Broughtons Pass Weir
Pheasants Nest Weir
AvonDam
NepeanDam Cataract
Dam
Bowral
WingecarribeeReservoir
Katoomba
Kowmung R
iver
LakeBurragorang
Wingecarribee River
Dam
Crookwell
ContentsExecutive summary 21 Introduction 6 2 Climate change projections 7
2.1 ClimateprojectionsforSydneyregion 9
2.2 Climatescenariosusedinthisstudy 10
3 Mitigation strategies 124 Climate change hazards and impacts 135 Adaptation 14
5.1 Toolsandsystems 15
5.2 Waterquantity 16
5.3 Waterquality 17
5.4 Environment 18
5.5 Landuse 19
5.6 Infrastructure 20
5.7 Supplychain 22
5.8 Business 22
5.9 Regulationandrelationships 24
6 Conclusion 26 References 27Acronyms 28Contact information 30
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Executive Summary Changesinclimaticconditions–intheformofincreasedclimatevariability,longer-termaverages,alteredrainfalldistributions,increasedfrequencyand/orintensityofextremeweather-relatedevents–arelikelytohavebroad-rangingimplicationsfortheSydneyCatchmentAuthority(SCA).AcomprehensiveclimatechangeimpactassessmentcompletedbytheSCAin2010hasemphasisedthecomplexityoftheinterrelationsbetweenwaterquantity,waterqualityandcatchmentcondition,andhighlightedthepotentialimpactsofclimatechangeonSCAoperations,infrastructure,businessandregulation.
TheclimatefuturesusedinthisassessmentarebasedonrecentclimateprojectionscoveringSCAcatchmentareas.Projectionsoffutureclimatehavelargeuncertaintiesbecausecurrentmodelsareunabletocapturethecomplexityoffeedbackmechanismsintheearth-atmosphere-hydrospheresystem.Althoughthescienceofclimatemodellingisrapidlyimproving,modelsandprojectionsatbestpresentarangeofpossiblefuturestoconsiderinscenarioandbusinessplanning.SuchknownuncertaintyrequirestheSCAtobeadaptabletorapidchangeandapplyongoingsustainableandflexiblebusinesspracticestoensureresiliencetochangesinclimateandotherexternalforces.
Theimpactassessmentconsideredtwofutureclimatescenarioswithhighertemperaturesandmorevariablerainfallpatterns,andidentifiedandprioritisedimpactsviaaseriesofstructuredinternalworkshops.GroupsofSCAspecialiststhenidentifiedcurrentactivitiesorcontrolsthatpartiallymitigatethepotentialimpacts,andalsodevelopedarangeofresponsesthatcouldbeconsideredinthefuture.Theassessmentfoundthatoverall,theSCAhasahighdegreeofpreparednessformanyofthepotentialimpactsofclimatechange.WaterresourcemanagersinAustraliahavehistoricallyhadtodealwithahighdegreeofclimaticandhydrologicvariability.TheSCAhasidentifiedanumberofbusinessareaswhereimprovedplanning,additionalinvestmentandback-upsystemscouldassistinbuildingadaptivecapacityandbusinessresilience.
Itwasnotedthatexternalforcessuchaspopulationgrowth,changesingovernmentpolicyandinvestmentinsourcediversificationforpurposesotherthanclimatechangemayimpactontheSCAsoonerthanclimatechangeitself.
Theimpactassessmentfoundthatadditionalinvestmentsininfrastructure,modelling,toolsandpreparednesswouldassistinbuildingadaptivecapacityandbusinessresilience.ScenarioexercisesbasedonarangeofclimateandpopulationprojectionswouldinformstrategicplanningandpreparetheSCAforexpandedbusinessopportunities.ThefindingsoftheassessmenthavealreadybeenbuiltintotheSCA’sbusinessplanningaspartoftheCorporateSustainabilityStrategythatprovidestheSCA’sstrategicdirectionforthenextfiveyears.
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Climate change actions
Action 1 – Ensuring climate change scenarios are realistic TheSCAwillworkwithothergovernmentagenciesandresearchproviderstoexpandandimproveclimatemodellingtoencompassabroaderrangeofclimatescenariosandsimulatemulti-yearclimaticfluctuations.
Althoughthescienceofclimatemodellingisimprovingrapidly,modelsandprojectionsatbestpresentawiderangeofpossiblefuturestoguidebusinessplanning.Currentprojectionsoffutureclimatescenarioshavelargeuncertaintiesbecauseofchangingestimatesonemissionlevels,differencesbetweentheglobalclimatemodels,problemsinthesimulationofrealisticfloodanddroughtcycles(hydrologicpersistence),andtheinabilityofcurrentclimatemodelstocapturethecomplexityoffeedbackmechanismsintheearth-atmosphere-hydrospheresystem.
Action 2 – Reducing the SCA’s carbon footprint TheSCAwillcontinuetoinvestigateandimproveenergyefficiency,expandhydroelectricgenerationandassessthebusinessbenefitsofcarbonoffsetsaspartofitssustainabilitystrategy.
Muchattentionisbeingplacedonthedevelopmentofadaptationstrategiestodealwiththeimpactsofclimatechange.Thereisstilltheopportunitytoinfluencethedirectionandmagnitudeoftheoutcomesbyreducingthescaleofgreenhousegasemissions.
Action 3 – Quantifying the impact of climate change on water quantity and quality TheSCAwillreviewitsexistingmodelsaswellasanewgenerationofsoftwaretoassesstheirperformanceunderclimatechangescenarios.
TheSCAreliesheavilyonpredictivemodelsandanalyticaltoolstoinformcatchmentandreservoirmanagementdecisionsandearlywarningsystems.Achangingclimatewillchallengethevalidityofmanyofthesetools,asitmaydriveeventswhicharebeyondourhistoricalexperienceandthereforeoutsideofthecalibrationrangeofourexistingmodels.Asclimatechangeislikelytofundamentallyalterpreviouslyassumedlandandwaterrelationships,morerigorouscalibrationsandtestingofthemodelsisneededunderavarietyofclimatechangescenarios.
Action 4 – Increasing flexibility in the water supply systemTheSCAwillinvestigateincreasingtheflexibilityinthewatersupplysystem,includingincreasedcapacitytotransferwaterbetweendifferentpartsofthesupplysystem.
GreaterflexibilitywouldsignificantlyenhancetheSCA’sabilitytocopewithprojectedchangesinthedistributionofrainfall(wetterincoastalanddrierininlandpartsoftheSCAcatchments)aswellasincreasedwaterqualityrisks(egincreasedriskofcyanobacteriabloomscausedbylongerdroughtperiods,highertemperaturesandmoreintensiverainfallevents).
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Action 5 – Improving SCA’s capacity to monitor short-duration eventsTheSCAwillincreasetheemphasisonevent-basedsampling,offsetbyreducedeffortinroutinesampling.Mostclimatechangeprojectionsareindicatingincreasedstormactivityandhighintensityrainfallinsummerbetweenextendeddryperiods.Thisislikelytoresultinmorerapidandmoreextremechangesinwaterquality,andmorecomplexbehaviourshiftsinreservoirhydrodynamics.Monitoringofextremeevents(bothverylowandveryhighflows)hasalwaysbeenchallengingandyetwillbecomeevenmoreimportantasthisdataisneededtohelpimprovemodellingcapabilitiesandcalibrations.
Action 6 – Reviewing strategies and plans for sensitivity to climate change scenariosTheSCAwillreviewitscorporatestrategiesandplansofmanagementtoensuresensitivitytoclimatechangescenarios.
Climatechangesarelikelytohaveabroadimpactoncatchmentandstreamhealth,andontherelativecontributionsofpollutantsacrossthedifferentsources,andacceleratechangesinlanduseandregionaldevelopment.EvaluationoftheimpactoflandusesandtheinterventionsimplementedthroughtheHealthyCatchmentStrategyarelikelytobeconfoundedbyclimatechanges,whiletheplansofmanagementforSpecialAreasshouldbeexpandedtotakeintoaccountclimatechangeimplications.
Action 7 – Reviewing design specifications of existing critical infrastructureTheSCAwillinstigateanongoingprogramforthereviewofdesignspecificationsofexistinginfrastructure,plantandequipmenttoassessitsvulnerabilitytoextremeeventssuchasstorms,firesandfloods.
AchangeinrainfallpatternsandmoreseverestormeventscouldimpactawiderangeofSCAinfrastructure,includingcriticalcontrolsystemsatdams,pumpingstations,controlstructuresandmonitoringandtelecommunicationssystems.Morefrequentand/orhigherintensitybushfirescanalsothreateninfrastructure.
Action 8 – Building explicit consideration of climate change into new business initiatives and project designsSCAwillembedconsiderationsrelevanttoclimatechangeintoitsplanningandbusinessprocesses.TheSCA’ssustainabilityframeworkhasopportunitiestoalignclimatechangeresiliencewithforwardplanning.Climatechangeimpactsonsupplyandwaterqualitywillincreasetheneedtojustifyprojectexpenditureaswellasputpressureonrevenues.SCAbusinesscases,whicharealreadyrequiredtoincludesustainabilitycriteria,shouldaddressclimaterelatedrisksanddemonstratetheirpotentialtoimprovebusinessresilience.Businesscasesshouldalsoexplorealternativefundingoptionsandeconomicmodels.
Action 9 – Increasing preparedness to manage concurrent or extreme incidentsTheSCAwillimproveitsworkforce’sadaptivecapacityandresponsivenessbyinvestinginskillstrainingandprofessionaldevelopmentforitsstaff.Preparednessformanagingextremeorconcurrentincidentsisabusinessreality.
Highertemperatureandmoreseverestormsarelikelytoleadtoanincreaseinthenumberandcomplexityofdeclaredincidents.Duringaconcurrentorextremeincidentkeyinfrastructurewouldchallengeoperatingproceduresandorganisationalresilience.TheSCA’sincidentresponseandscenario-basedcontingencyplanningarewelldeveloped.TheSCAwillincreaseitsattentiontoincidentmanagement,businesscontinuityanddisasterrecoveryplanningtoensurethatSydney’srawdrinkingwaterismanagedtointernationalbestpractice.
Action 10 – Improving communication and knowledge exchange on climate change TheSCAwillbeproactiveincommunicatingwithcatchmentcommunitiesandthebroaderSydneycommunityregardingtheimpactsofclimatechange.
Changesinsecurityofsupply,watersourcemanagementandwaterqualityresultingfromclimatechangecouldimpactonpublicconfidenceintheSCA’sabilitytodeliverreliablequalitywater.Neworexpandedoutreachprogramswillbeneededtomanagecommunityexpectationsofwaterqualityandsupplyissues.
Adaptingtoclimatechangewillrequirechangesinlandpracticesandprobablycatchmentdevelopmentcontrols.TheSCAwillneedtosupportlocalcouncilsandlandholderstounderstandthechangingcircumstancesandtheimpactsonwaterandtheenvironment,andprovideassistanceinmakingtherequiredchangestolegislationandbestmanagementpractices.
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1 IntroductionClimate change challenges the traditional assumption that past hydrological experience provides a good guide to future conditions 1
ThewatersupplysystemmanagedbytheSCAanditspredecessorshasdevelopedinresponsetothevariableclimateoftheSydneyregionandsteadypopulationgrowth.TheMetropolitanWaterPlan(MWP)2004andsubsequentrevisionscompriseanadaptive,integratedapproachtowatermanagementthroughacombinationofdiversificationofsupplyanddemandmanagement.AcollaborativestudyontheprojectedimpactofclimatechangeonsupplyanddemandhasbeenundertakenundertheauspicesoftheMWP.However,risksimposedbyclimatechangearemuchwiderthancoveredintheMWPstudy,inparticularwithrespecttolanduse,waterqualityandinfrastructure.SydneyWaterhasconductedaclimatechangeriskassessmentofitsoperations(SWC,2008),ashaveotherutilities.AlthoughmanyoperationalareasoftheSCAhaveimplicitlyconsideredtheeffectsofclimatechangeandvariabilityintheirbusinessplans,thisefforthasnotbeencoordinatedorupdatedwiththelatestclimateprojections.
ToassessthebroaderimplicationsofclimatechangeontheSCA,acomprehensiveclimatechangeimpactassessmentwasconductedbetweenAugust2009andFebruary2010.Theassessmentinvolvedaseriesofworkshopswith30seniorstafffromacrosstheorganisation,precededbyseminarsonthescienceofclimatechange.TheworkshopsweredesignedtoassessthecurrentunderstandingofclimatechangewithintheSCA,determineclimateassumptionsbuiltintooperationsandplanning,andexplorethesensitivityofbusinessoperationstoprojectionsofclimaticextremesthatlieoutsidethosepreviouslyexperienced.
About1000potentialimpactswereidentified,andlaterconsolidatedinto171hazardandimpactstatementsinninecategories:waterquantity,waterquality,toolsandsystems,infrastructure,environment,landuse,supplychain,business,andregulationandrelationships.FocussedworkshopswithkeystafffromSCAbusinessunitsthenreviewedtheclimateimpacts,assessedcurrentcontrolsanddevelopedarangeofmanagementactionsthatcouldreduceanypotentialclimateimpacts.
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1 Climate Change and Water, Intergovernmental Panel on Climate Change, 2008, 192 pp
2 Climate change projections
TheIntergovernmentalPanelonClimateChange(IPCC)wassetupbytheWorldMeteorologicalOrganizationandtheUnitedNationsEnvironmentProgrammein1988tosummariseandassessthevastarrayofpeer-reviewedscientificliteratureonclimatechange.TheIPCCpublishedassessmentreportsin1990,1995,2001and2007.Tostandardiseassumptionsofgreenhousegasesforclimatemodelling,theIPCCpreparedaseriesoffutureemissionscenariosforuseinthethirdandfourthassessments.
TheFourthIPCCAssessment(IPPC-4),Climate Change 2007,isthemostdefinitiveintermsoflinkingobservedclimatechangetoanthropogenic(human-induced)generationofgreenhousegases.AnIPCC2008technicalpaper,Climate Change and Water,focusesontheimpactofprojectedclimatechangeontheworld’sfreshwatersystems.
Implicationsofthe2001IPPC-3findingsforAustraliaweresummarisedinClimate Change in Australia,publishedin2007(CSIRO,2007a).AreasmostatriskwereidentifiedastheMurray-DarlingBasin,GreatBarrierReefandsouthwestWesternAustralia,withbroad-scaleprojectionsincludinga40%higherchanceofdroughtineasternAustraliaby2070.
TheNSWGreenhouseOffice,nowpartoftheDepartmentofEnvironment,ClimateChangeandWater(DECCW),commissionedCSIROtoassessprojectedchangesinaverageclimateandclimateextremesforNSWoverthenext70yearsbasedonmodellingoutputsfromthe2007CSIROstudy,whichinturnwasbasedonthe2001IPPCassessment.AseriesofindividualreportsontheimpactofclimatechangeforindividualCatchmentManagementAuthoritiesinNSWwerealsopublished(CSIRO2007b).Theseprojectionsarebasedon200kmgridcellsandareunabletoprovidetheresolutionneededforregionalstudiesrequiredbytheSCA.
In2009DECCWcommissionedtheUniversityofNSWtodevelopregional-levelclimaticprojectionsoftemperatureandrainfallfornineStatePlanregionsofNSWfortheyear2050.TheNSW Climate Impact ProfileformspartofAction in a Changing Climate(CCAP)whichdescribesactionstobetakenoverthenextfiveyearstorespondtothechallengeofclimatechange.Theprojectionsarebasedonamodellinggridsizeof200kmto300kmwithinterpolationdownto50kmx50km,andhavehighuncertaintiesaroundcoastalregions.
TheconsensusofclimatescientistsisthatmanyareasofAustraliaarealreadyshowingevidenceoftheeffectsofclimatechange,forinstancedecadesofreducedrainfallandrunoffintheMurray-DarlingBasinandsouthwestWesternAustralia.TheunprecedentedhightemperatureswhichcontributedtotheseverityoftheFebruary2009bushfiresinVictoriawasalsoaclearclimatechangesignal.HoweverthedatafortheSydneyregionismoreequivocalandaveragerainfallhasnotbeentoodifferentfromlong-termaverages.ItisinstructivetonotethattheclimateinSydney’scatchmentareasisinfluencedbyinteractionsbetweensoutherncirculationpatternsdrivenbytheSouthernAnnualMode(SAM)overAntarctica,IndianOceanseasurfacetemperatures,andnortherncirculationpatternsmorecloselycorrelatedwiththeElNiñoSouthernOscillation(ENSO).Thisinteractionismorecomplexthanclimatedriversinthenorthorsouthofthecountry.Note,also,that SCAClimateChangeImpact
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rainfallismoredifficulttomodelthanotherclimaticparameterssuchasairpressureandtemperature.
ThemostrecentIPCC-4reportisbasedonpeer-reviewedscientificpapersthatarenowatleastfiveyearsold.Themostrecentscientificdataindicatesthatgreenhousegasemissionsandglobalwarmingobservationsaretrackingonorabovetheworse-casescenarioconsideredbytheIPCCinits2007report.
Regional climate modelsTheclimateprojectionscontainedintheIPCCreportsarecalculatedusinglarge-scalethree-dimensionalmodelswithgridcellsof200kmto300km.Moredetaileddownscaledmodelsarerequiredtomodelclimateonthefinerscalerequiredforwatersupplyplanningatacatchmentlevel.Suchmodelsarecomplexandrequirelargeamountsofcomputingpower.
ModellingrecentlyundertakenbytheCSIROandUniversityofNSW(NSWOfficeofWater,2010)fortheSCAaspartoftheclimatechangesupply-demandcomponentoftheMWPisdownscaledtoa4kmgridsizewhichbettercaptureslocaltopographicandmesoclimateeffects.
Limitations in climate modellingClimateprojectionsarepresentedasarangeordistributionofpossibleclimates–temperatureandaverageorseasonalrainfall–thatareplausibleunderfuturegreenhousegasscenarios.
Oneofthedangersinusingtheoutputsfromclimatemodelsistheadoptionofunrealisticexpectationsoftheaccuracyorcertaintyoftheclimateprojections.Evenwhenrangesformodelrunsaregiven(egtemperaturesvaryfrom+0.2°Cto+5.6°C),thereisanatural,butincorrect,tendencytoassumethecentralvalueas‘mostlikely’.
Moreimportantly,globalclimatemodelscannotyetreproduceinter-decadalcyclessuchasdrivenbyENSOevents,andcannotreproducemulti-yeardroughtsandextendedperiodsofhigherrainfall.Consequently,mostrunoff/yieldstudiesmakeassumptionsinthedegreeofyear-to-yearcorrelation,or‘persistence’infutureclimates.IntheMWPSydneystudyitisassumedthatthefuturepersistenceissimilartothatobservedinthehistorical(100-year)recordintheabsenceofmoreappropriateclimatemodels.Theresultant‘systemyield’isstronglydependentontheassumedpersistence.
Climate extremes and variabilityAtalocallevel,itisdifficulttodistinguishbetweenclimatevariabilityandclimatechange.Inareassuchassouth-easternAustralia,naturalclimatevariabilityexhibitswidefluctuationsyear-to-yearanddecade-to-decadecomparedtolong-termtrendsprojectedinclimatechangescenarios(Figure1).
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Figure 1. Time series of mean annual maximum temperature anomalies in NSW between 1950 and 2003. The red and blue bars are percentage of NSW in the top (hot - red) and bottom (cold - blue) deciles compared to the average between 1961 and 1990 (from Climate Change in New South Wales: Hennessy et al, 2004a).
2.1 Climate projections for Sydney regionThemostdetailedclimatestudyatthescalerequiredbytheSCAistheClimate change impacts on water supply and demand in Sydney(NSWOfficeofWater,2010),whichwasconductedaspartoftheMWP.
Examplesofclimateprojectionsfromthisstudyinclude:• Increaseinrainfallandstreamflowinmetropolitancatchments.• ReducedrainfallandstreamflowinWarragambaandShoalhaven
catchments.• Increaseinsummerrainfallduetostrongeronshoreairflows,slight
decreaseinwinter.• Numberofdaysofextremerainfall(>40mm/day)increasesby45%in
summer.• Increaseinfrequencyofcontinueddryspells(15daysormore).• Doubleinfrequencyofhot(>32°C)andveryhot(>37°C)days.• Evaporationincreasesby10%withdoublethenumberofveryhigh
evaporationdays.
Themostseriouslimitationsofthisstudyarethatresultsarebasedonasingleglobalclimatemodel,andtheassumptionthat‘persistence’(year-to-yearcorrelation)issimilartothehistoricalrecord.
OtherstudiesrelevanttotheSCAcatchmentareaincludeRainfallextremesunderclimatechangeconductedbytheCSIROfortheSydneyMetropolitanCatchmentManagementAuthority(CMA)andpartners(Abbs,inprep),andNSWClimateImpactProfile(DECCW,inprep).ThesestudiesontheanticipatedeffectsofclimatechangeineasternNSWandlocallyintheSydneyregiondemonstratethewidescatterinclimaticvariablesthatarisefromclimatemodellingandtheinherentuncertaintiesinclimateprojections.
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TheSCA’ssystemyieldprojectionsarebasedonhistoricalhydrologicalrecordswhichareunrepresentativeunderclimatechangescenarios.Ontheotherhand,currentprojectionsoffutureclimatescenarios(includingrecentclimatemodellingundertakenfortheMWP)aresubjecttolargeuncertaintiesforanumberofreasonsincluding:• inabilitytosimulaterealisticfloodanddroughtcycles(hydrologic
persistence)• changingestimatesonemissionlevels• differencesbetweentheglobalclimatemodels• inabilityofcurrentclimatemodelstocapturethecomplexityoffeedback
mechanismsintheearth-atmosphere-hydrospheresystem.
AmajorknowledgegapexistsontheevaluationandselectionofclimatemodelsanddownscalingtechniquesfortheSCAcatchmentareas.AsingleclimatemodelwasusedintheMWPclimatestudy,andthemodeloutputscouldnotsimulatemulti-yearcorrelations(persistence)ofdroughtandrainperiods.Asclimaticmodellingtoolsarecontinuallyimproving,thiswilllikelybeanareaofongoingresearcheffortfortheSCA,workingwithotheragenciesandindustrybodiesasappropriate.
Althoughthescienceofclimatemodellingisimprovingrapidly,modelsandprojectionsatbestpresentawiderangeofpossiblefuturestoguidebusinessplanning.
Climate Change Action 1 – Ensuring climate change scenarios are realistic
SCA Corporate Sustainability Strategy key focus area: Stakeholder relationshipsTheSCAwillworkwithothergovernmentagenciesandresearchproviderstoexpandandimproveclimatemodellingtoencompassabroaderrangeofclimatescenariosandsimulatemulti-yearclimaticfluctuationsandafocusonyear-to-yeardroughtandrainfallcorrelations.
2.2 Climate scenarios used in this studyTworepresentativeclimatechangescenariosweredevelopedforSCA’sclimatechangeimpactassessment.Eachscenarioisaplausibleclimaticconditionthatcouldariseatsometimeduringthenext50years.Thescenariosaresufficientlydifferenttocurrentclimatetochallenge‘businessasusual’andarewithintherangeofprojectedimpacts.
Scenario1–Warmerandstormier–wasdesignedtoexplorethefullrangeofimpacts,bothinternalandexternal,thatcouldaffecttheorganisationinachangingclimate.
Scenario2–Hot,dryandstormy–ismoreextremebutstillplausible,andwasusedtotestthecompletenessofthelistofimpactsidentifiedinScenario1.
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Scenario 1: Warmer and stormier• Increasingfrequencyofeastcoastlowsbutextendedperiodsofdry
westerlywinds.• Similaraverageannualrainfallbutlongerdryspells.• Heavierrainfallfromstormeventsduringsummer.• Hotterweather,higherevaporationrates.
Scenario 2: Hot, dry and stormy• Clearclimateshift,weathersystemsmovesouth.• MoresevereElNinoperiodsbringmuchhotterweatherandextended
droughts.• IncreaseinTasmanhighsbringsmoreintensebutinfrequentstorm
events.• Coastaldominatedweathersystems,withmorestormeventsinsummer.• Verydryinland.
Temperature Rainfall Evapotranspiration WindIncreaseby3°Conaverage
Similaraverageascurrentclimate,butincreaseinsummerrainfallanddecreaseinwinterrainfall
10%increaseinsummerandspring
Summerpeakwindspeedsincreaseby10%
Highermaximaandhigherminima
Spatialredistribution–morecoastalrainfall
Doublenumberofhighevaporationdays
Heatwaves(>35oC)twiceascommon
Extendeddryspells
Increasednumberofconsecutivedaysoflightrain
Temperature Rainfall Evapotranspiration WindIncreaseaverageby6°C
20%decreaseintotalrainfall,butincreaseinproportionthatfallsinintense,shortbursts
20%increaseinsummerandspring
Peakwindspeedsincreaseby30%
Moreintenseandfrequentheatwaves
Spatialredistribution–increasedcoastalrainfall(metropolitandams)insummerandautumn.DecreaseinShoalhavencatch-ment.Verydryinland
Highermaximumandhighermini-mumtemperatures
Longerdryspells,multi-yeardroughts
3 Mitigation strategies Whilemuchattentionisnowbeingplacedonthedevelopmentofadaptationstrategiestodealwiththeimpactofclimatechange,thereisstillsignificantopportunitytoinfluencethedirectionandmagnitudeoftheoutcomesbyreducingthescaleofgreenhousegasemissions.Mitigationstrategiesareincreasinglyreflectedingovernmentpolicywithresultantimpactsoncarbonpricing,renewableenergytargets,andelectricityandfuelcosts.
Aspartofitssustainabilitystrategy,theSCAisalreadyseekingtoexpanditsuseofhydroelectricityplantstoreduceitsdependenceoncarbonfuelenergy,investigatingimprovementsinenergyefficiencyandinvestigatingbusinessopportunitiesforcarbonoffsets.
Climate Change Action 2 – Reducing the SCA’s carbon footprint
SCA Corporate Sustainability Strategy key focus area: Resource optimisationTheSCAwillcontinuetoinvestigateandimproveenergyefficiency,expandhydroelectricgenerationandassessthebusinessbenefitsofcarbonoffsets.TheenvironmentalfootprintofSCA’sworkforcecouldbeimprovedbytheuseoftele-andvideo-conferencingand,whereappropriate,activeencouragementoftelecommutingandotherinitiativestoreducegreenhousegasemissions.
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4 Climate change hazards and impacts Climatechangeimpactscanbeanalysedatanumberoflevels.Atthehighestlevelaretheprimaryclimaticvariables(egtemperature,rainfall,evaporation,wind)thatleadtoasecondaryhazard(egincreasedbushfires,shortintensestorms)whichwillgeneratearangeofresourceandbusinessimplications(egincreasederosionandturbidity,greaterbushfiredamage).ThefinallevelencompassesmanagementandcostimplicationsontheSCAanditsstakeholders(egagreementswiththeRuralFireService,disruptionstopowersuppliesandtelecommunications,impactsonpublicsafety).
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Primary climatic hazard
• Increasedtemperaturesandtemperaturevariability
• Changesinrainfalldistribution,frequencyandvariability
• Extremeweatherevents–changesinfrequencyandseverityoffloods,fires,highwindsandlightning
Secondary hazard
• Driersoilsleadingtochangesinrainfall-runoffrelationships
• Increasedbushfirerisk
• Highererosionratesincreasesedimentloadandturbidity
• Increasednutrientloadsandmorefrequentalgalblooms
Implications
• Increasedneedforfire-fightingresources
• Interruptionstocommunications
• Electricitydisruptionsandpumpingstationshutdowns
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5 Adaptation Theterm‘adaptation’inthecontextoftheSCAclimateimpactstudyreferstoactionsthatcanbetakenbytheSCAtoincreaseitspreparednesstodealwithclimatechangeimpactsasandwhentheyarise.Theseactionsmustbedesignedtobuildorganisationalresiliencetoincreasedvariability,severityandunpredictabilityofeventsrelatedtochangesinclimate.AdaptationalsoincludesactionsthatcanbetakenbytheSCAtoachievesustainablebusinessoutcomesinresponseto,andinanticipationof,government,economicandsocialchangethatcouldoccurasaresultofclimatechange.Someoftheseactionsarealreadypartofroutinebusiness;othersrequireadditionalinvestmentornegotiationwithexternalagencies.
TheadaptationresponsesweredevelopedthroughaseriesofninefocussedworkshopswherespecialistsinrelevantSCAbusinessunitscriticallyreviewedthepotentialimpactsandidentifiedexistingcontrolsoractionsthatshouldlessenorpartiallyaddresstheimpactacrossninethemeareas:
1. Toolsandsystems2. Waterquantity3. Waterquality4. Environment5. Landuse6. Infrastructure7. Supplychain8. Business9. Regulationandrelationships
Workshopparticipantsalsoidentifiedadditionalactionsorresponsesthatcouldbeconsideredinthefuture,subjecttofurtherfeasibility,riskassessmentandcost-benefitstudies.Participantsthenrankedtherelativeimportance(low,medium,high)ofeachimpactintermsofthepotentialsignificanceontheorganisation.
Thirtypercentoftheimpactswereconsideredhighimportance,withthebalanceequallydistributedbetweenlowandmediumimportance.Thelargestnumberofhighimportanceimpactswasidentifiedintheinfrastructurecategory,followedbyenvironmentandwaterquantity.TherelativerankingswithineachoftheninethemeareasareshowninFigure2.
Figure 2. Climate change impacts grouped into major themes and ranked by relative importance.
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TheninegroupsofcontrolsoractionsweresubsequentlysortedaccordingtothekeyfocusareasintheSCACorporateSustainabilityStrategy,toensuretheactionsareembeddedintheSCA’splanningframework.
Overall,theSCAhasahighdegreeofpreparednessforhandlingmanyofthepotentialimpactsofclimatechange.InpartthisisduetothefactthatwaterresourcemanagersinAustralia(includingtheSCA)havehistoricallyhadtodealwithahighdegreeofclimaticandhydrologicvariability.Thereforearangeofcontrols(operations,policiesorprocedures)andinbuiltflexibilityisalreadyinplace,whichcanbeacceleratedifneeded.However,theSCAhasidentifiedanumberofbusinessareaswhereimprovedplanning,additionalinvestmentandback-upsystemscouldassistinbuildingadaptivecapacityandbusinessresilience.
Thefollowingsectionssummarisetheidentifiedbusinessvulnerabilities,existingcontrolsandpossibleresponsesaccordingtothekeyfocusareasoftheSCA’sCorporateSustainabilityStrategy.
5.1 Tools and systems
Key vulnerabilities• Increaseinflowvariabilityacrossstorages.• LowerinflowsintoWarragambaDamandTallowaDaminShoalhaven.• MoreinflowsintoMetropolitanstorages(Avon,Cataract,Cordeaux,
NepeanandWoronoradams).• Changesintheorigins,amount,andtimingofpollutantloads.
TheSCAreliesheavilyonpredictivemodelsandanalyticaltoolstoinformcatchmentandreservoirmanagementdecisionsandearlywarningsystems.Achangingclimatewillchallengethevalidityofmanyofthesetools.Thisisbecauseclimatechangemaydriveeventswhicharebeyondourhistoricalexperience(andthereforeoutsideofthecalibrationrangeofourexistingmodels),andbecauseclimatechangeislikelytofundamentallyalterpreviouslyassumedlandandwaterrelationships.TheSCAisbuildingimprovedmodelsofcatchmentstreamflowandtransportofpollutantsduringwetweatherevents.Itisalsoundertakingareviewofbothitsexistingportfolioofmodelsaswellasthenewgenerationofmodelsavailableforsimulatingcatchmentrunoff,pollutantinstreamflows,instreamfateandtransportofpollutantsaswellasgroundwater-surfacewaterinteractionsunderclimatechangescenarios.TheSCA’scurrentwatermonitoringreviewisconsideringimprovementstothemonitoringnetworktoensureitcansupportfuturemodellingneeds.
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Climate Change Action 3 – Quantifying the impact of climate change on water quantity and quality
Corporate Sustainability key focus area: Reliable waterTheSCAwillcompleteitsreviewofmodelsincludinganassessmentoftheirperformanceunderclimatechangescenarios.Existingmodellingtoolswillbereviewedforsensitivitytoassumptionsonclimaticparametersandrevisedasnecessary,andsensitivityrunsofthemodelswillbeundertakenunderavarietyofclimatechangescenariostogetherwithmorerigorouscalibrationtoimprovemodelpredictionsunderbothdroughtandextremewetweatherevents.Modelswillneedtobeabletoefficientlyhandlestatisticalprobabilitydatasetsaswellashistoricdatasetsandwherepossible,catchmentandreservoirmodellingwillneedtobemorecloselycoupled.SCA’smonitoringprogramwillbemorecloselyalignedwiththeinputandoutputofitsmodellingtools,sothatmodelscanbere-calibratedasrainfallpatternsandinflowschange,affectingbothwaterqualityandyield.Monitoringofextremeevents(bothverylowandveryhighflows)willbereviewedandintegratedwithimprovedmodellingcapabilitiestoimprovemodelcalibrationsattheextremesandtobetterinformtheassessmentofclimateimpacts.Therewillbeincreasedemphasisonevent-basedsamplingpossiblyoffsetbyreducedeffortinroutinesampling.
5.2 Water quantity
Key vulnerabilities• Decreasedsystemyieldaffectingbothreliabilityandsecurity.• Increaseinflowvariabilityacrossstorages.• LowerinflowsintoWarragambaDamandTallowaDaminShoalhaven.• MoreinflowsintoMetropolitanstorages(Avon,Cataract,Cordeaux,
NepeanandWoronoradams).
Totalcatchmentyieldislikelytodecreaseduetohigherevapo-transpirationandincreasedsoilmoisturedeficit,aswellasincreasedlocalinterceptionofrunoffbylandownersexpandingtheiruseoffarmdamsandgroundwaterbores.Evaporationwillbeanincreasinglyimportantconsideration.ChangesinrainfalldistributioncouldlowerinflowsintoWarragambaandplaceincreasingdependenceontheMetropolitanstorages.
Highertemperaturesandextendeddroughtsincreasetheriskofmajorwaterqualityincidentsinthestorages(egcyanobacterialbloominWingecarribeereservoir)andwillrequiremoreflexibilityaroundalternatesuppliesandtransferoptionsifindividualstoragesaretakenoff-lineforextendedperiods.
TheSCAhasarangeoftoolstoassisttheassessmentandplanningofwatersupplyoptionsunderawiderangeofscenarios.Wathnetsystemmodellingenablestheefficientassessmentofalternatefuturescenarios,depletion
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projectionsandyieldriskstudies.DeepwaterpumpingstationsandgroundwaterreadinesshavebeenextendedaspartoftheMWP.AcaseforexpansionofthecapacitythroughreplacementoftheUpperCanalisbeingdevelopedandothertransferoptionsarebeingconsideredaspartofstrategicsupplyplanning.
Climate Change Action 4 – Increasing flexibility in the water supply system
Corporate Sustainability key focus area: Reliable waterFurtheropportunitiesforincreasingsupplyflexibilityacrossthesystemwillbeinvestigatedincludingenhancedtransfercapabilities,and/orgreaterlocalstorage(surfacewater,groundwaterandpotentiallyabandonedmines)intheMetropolitanandShoalhavensystemstomaintainreliabilityofsupply.
5.3 Water quality
Key vulnerabilities• Higherfrequencyand/orintensityofextremewetweatherevents
increasesthepotentialforlargescalemobilisationandtransportofpollutantstowatersupplyofftakes.
• Morefrequentorlargercyanobacterialbloomsinstorages.• Differentcyanobacterialassemblagewithpotentiallyhighertoxicityor
tasteandodourcompounds.• Reducedresilienceofaquaticecosystems.• Potentialdestabilisationoflakeecosystemsleadingtotippingpointin
biologicalintegrityandemergenceofnewdominant‘pest’species.• Bushfiresandstormscompromisewatermonitoringstations.
Mostclimatechangeprojectionsareindicatingincreasedstormactivityandhighintensityrainfallinsummerbetweenextendeddryperiods.Thisislikelytoresultinmorerapidandmoreextremechangesinwaterquality,andmorecomplexbehaviourshiftsinreservoirhydrodynamics.Large,intensebushfirescouldresultinlargequantitiesofash,phosphorous,nitrogenandorganicmatterbeingwashedintostoragesifheavyrainfellwithinseveralweekstoayearafterthefire.
Anincreaseinextremewetweathereventsmayresultinanincreasedriskofmajorpollutionincidents.Thefrequencyorscaleofcyanobacterialbloomsinstoragesmayalsoincreaseasaresultofthecombinationoflowerwaterlevelsandincreasednutrientloadingduringextremerainfalleventsand/orthemobilisationofnutrientsfromlakebedsediments.Changesinhydrodynamicorchemicalconditionsmayalsofavourtheemergenceofnewdominantcyanobacterialspecieswithgreatertoxicityortasteandodourthanpreviousbloomsandwouldcausemajorproblemswithmanagementandtreatment.
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Monitoringofextremeevents(bothverylowandveryhighflows)hasalwaysbeenchallenging.ExistingSCAmonitoringprograms(waterquality,hydrometricandmeteorological)arenotoptimisedformeasuringshorterdurationandsporadicrainfallevents.Highertemperatureandmoreseverestormswouldlikelyleadtoanincreaseinthenumberandcomplexityofdeclaredincidents.ConcurrentincidentsorcascadingfailuresofkeyinfrastructurewouldchallengetheSCA’soperatingproceduresandorganisationalresilience.
Climatechangesarealsolikelytohaveabroadimpactoncatchmentconditionandstreamhealth,andonregionaldevelopmentpatternsandassociatedlandusechanges,andonthemanagementpracticesadoptedwithinexistinglandusecategories.Thesewillallultimatelyimpactontherelativecontributionsofpollutantsacrossthedifferentsources.TheymayalsoconfoundtheevaluationoftheimpactoflandusesandtheinterventionsimplementedthroughtheHealthyCatchmentsStrategy.Itwillbemoredifficulttoassesstheimpactofcatchmentinterventionswhenwaterqualityobservationsareconfoundedbychangesinclimate,andmoresophisticatedmodellingandevaluationtechniqueswillberequired.
Thewatersupplysystemalreadyprovidesmanagementoptionstohandlewaterqualitychallengessuchasofftakeselection,systemtransfers,alternatesources,on-lineaccesstohydrodynamicandwaterqualitydataandlimitedeventmodellingcapability.TheSCA’sincidentresponseandscenario-basedcontingencyplansarereasonablycomprehensive.Researchandinvestigationsintothecauseandbehaviourofwaterqualityeventscontinuestoaidmanagementpreparednessandtheidentificationofsuitableresponses.ResearchintothecausesandeffectsofwaterqualityincidentsassociatedwithextremewetweatherisbeinggivenpriorityattheSCAandnationally,throughWaterQualityResearchAustralia(WQRA).TheSCAisalsoapartnerinanAustralianResearchCouncillinkageprojectattheUniversityofNewSouthWaleswhichisinvestigatingtheimpactofclimatechangeinSCA’sSpecialAreas.
Climate Change Action 5 – Improving capacity to monitor short-duration events
Corporate Sustainability key focus area: Reliable waterMonitoringofextremeevents(bothverylowandveryhighflows)willbecomeamajorfocusoffuturemonitoringandresearch,particularlyasthisdataisneededtohelpimprovemodellingcapabilitiesandcalibrations.
5.4 Environment
Key vulnerabilities• Lossofwetlands,possiblypermanent.• PotentialdestabilisationofpeatswampandmassinWingecarribee
Reservoir.• Deteriorationofripariancorridors.
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• Reducedresilienceofterrestrialandaquaticecosystemsleadstoirreversiblechangestobiologicalintegrityandemergenceofnewdominant‘pest’speciessuchascyanobacteria,weedspeciesandpestanimals.
• Lesswaterforenvironmentalflows.• Extendedbushfireseasonwithmoreintensefires.• Vegetationcommunitycouldshifttowardsmoredrought-tolerantorfire-
resistantspecies.
Thenaturalenvironmentprovidesawiderangeofecosystemservicestoprotectwaterqualityandbaseflowintostreams.Changesinclimatearelikelytohaveabroadimpactonbothterrestrialandaquaticecology,affectingcatchmentandstreamhealth,biodiversityandenvironmentalcondition.Theremayalsobesecondaryflow-onenvironmentalimplicationsfromchangestoSCAoperationssuchaswatertransferandenvironmentalflows.
TheHealthyCatchmentsStrategy,includingplansofmanagementofSpecialAreas,StateEnvironmentalPlanningPolicy(SydneyDrinkingWaterCatchment)2011(SEPP),bushfiremanagement,riskandoperationalplansareinplaceandaregenerallyflexibleenoughtohandlechangesincatchmentconditions.
ItwillbeincreasinglydifficulttodifferentiatebetweenoutcomesfromactivecatchmentinterventionbytheSCAandenvironmentalandwaterqualitychangescausedbyclimatechange.Increasingly,moresophisticatedmodellingandevidence-basedevaluationtoolswillberequired.
TheSCAshouldworkcloselywithotheragenciessuchasDECCWandresearchproviderstoimproveassessmentofecologicalconditionandenvironmentalstressors.Theongoingdevelopmentofknowledgerelatingtotheimpactoffireonwaterqualitywillneedtobereflectedinrevisionstofiremanagementpolicies.
5.5 Land use
Key vulnerabilities
• Changesinlanduse(egcropandgrazingtypeandintensity)andretirementofmarginalland,displacedcommunities.
• Increaseinlocalwaterextraction(groundwaterandsurfacewater).• Inadequatestormwaterdesignintownshipsandsewagetreatmentplants
(pointsourcepollutants).• Increaseofdiffusesourcepollutants.• Increasedunderstandingoftheroleofbio-sequestration(bothin
improvingsoilcarboncontentandrevegetation)incarbonmarketswillopenopportunitiesforlandownersandtheSCAinalternativelanduses.
Thedemographicsandmakeupoflocalcommunitiesarelikelytochangeasexistingagriculturebecomeslessviableandhobbyfarmsandretirementacreageincrease,particularlyalongtheSydney-Goulburngrowthcorridor.Thisdemandonlocalwatersupplies,combinedwithapossibleincreaseinthenumberandsizeoffarmdamsandlocalretentionstructurestooffsetreducedrainfallininlandareas,willdecreasetherunoffintostreamsandSCAreservoirs.
ModuleswithintheHealthyCatchmentsStrategyshouldincorporatenewclimatescenariosandprojectionsastheybecomeavailable.TheseincludetheNeutralorBeneficialEffect(NorBE)toolkit,theStrategicLandandWaterCapabilityAssessment(SLWCA),andtheCatchmentDecisionSupportSystem(CDSS),aswellasrurallanduseguidelinesandrecommendedbestmanagementpractices,SewageTreatmentPlan(STP)design,andCMAincentives.ItwouldbebeneficialtoupgradeSCAmonitoringprograms(waterquality,hydrometricandmeteorological)sothattheycanmeasureshorterdurationandsporadicrainfallevents,andmodelsimprovedtobetterunderstandtheimpactofchanginglanduseandclimate.
TheSCAshouldbeproactiveinidentifyingandencouragingnewpracticesthatimprovewaterquality,butnotattheexpenseofrunoffandyield.TheSCAcouldpotentiallyexpanditsCurrentRecommendedPractice(CRP)program.
Climate Change Action 6 – Reviewing strategies and plans for sensitivity to climate change scenarios
Corporate Sustainability key focus area: Reliable waterClimatechangewillbeexplicitlyconsideredinfuturerevisionsoftheHealthyCatchmentsStrategy.DecisionsupporttoolssuchastheCDSS,theNorBEtoolkit,andtheplansofmanagementfortheSpecialAreaswillallneedtorecognizeandbeadaptabletotheprogressivechangesinclimate,catchmentresponseandlandusepatterns.
5.6 Infrastructure
Key vulnerabilities• Moreintensestorms,highwindsandlightning,highertemperaturesand
increasedbushfireweather.Criticalsystemfailurefordams,pumpingstations,controlstructuresandotherfacilities(egon-sitepowersupplies,controlsystems,communications,actuators,pumps,watermonitoringstationsandradiotelemetryassets).
• Flood,waterorhaildamagetoSCAinfrastructure(includingtelemetryandcommunicationssystems).
• Watersupplyinfrastructurenotsuitedtochangedinflowpatterns.• FlooddesignbasedonAustralianRainfallandRunoff(ARR)andProbable
MaximumFlood(PMF)estimatesinadequate.• Debrisingatesandofftakes,weirfailure.
AchangeinrainfallpatternsandmoreseverestormeventscouldimpactawiderangeofSCAinfrastructure,includingcriticalcontrolsystemsatdams,pumpingstations,controlstructures,monitoringandtelecommunicationssystems.Morefrequentand/orhigherintensitybushfirescanalsothreateninfrastructure.Regulatoryrequirementsfordamsandweirsarelikelytobereviewedandrevisedunderclimatechangewithpotentialinfrastructureimplications.SCAClimateChangeImpact
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TheSCA’swatertransfersystemcouldbechallengedbytwopotentialimpactsofclimatechange:• Achangeinrainfallpatterns(eghigherrainfallinmetropolitan
catchments)couldcreateincreasedrelianceontheUpperCanaloritsreplacementforSCAsupplytogreaterSydneyand/orincreasedtransfervolumesbetweenMetropolitandams.
• IncreasedcompetitionfromdesalinationandincreasedsupplyfromtheMetropolitanDamscouldaffectSCAwatertransferoperationstoProspectusingtheWarragambaPipelinewhichiscurrentlyconstrainedbyminimumflowrequirements.
Ananticipatedincreaseinclimaticextremeswillputstressontelecommunicationinfrastructurethatsupportsdatacollectionsystems.Moreintensebushfirescouldresultinfailureofcriticalsystemsatdams,pumpingstationsandcontrolstructures.AchangeinrainfallpatternsandmoreseverestormeventscouldimpactawiderangeofSCAinfrastructure,includingcriticalsystemsatdams,pumpingstations,controlstructuresandtelecommunicationsystems.Morefrequentbushfireweatherandhigh-intensitybushfireswouldhaveflow-oneffectstowaterquality,yieldanddamagetoinfrastructure.Thedesignspecificationsofcriticalinfrastructureshouldbereviewedandthevulnerabilityoftelecommunicationlinksandcriticalmonitoringsitesassessed.Regulatoryrequirementsfordamsandweirscouldbealteredunderclimatechange.Furthermodelingofprobablemaximumfloodsunderrevisedclimatemodelswouldassistinplanningupgradesorchangestooperatingregimessuchaspre-releaseinadvanceofflood.
Designspecificationsaresubjecttoregularreview,andmanycriticalsystemcomponentsincorporateredundancyandareconsideredincontingencyplanning.Improvedemphasisonresiliencetoextremeeventswouldbebeneficial.Damsandweirsmeetcurrentregulatoryrequirementsbasedonhistoricalestimatesofpeakfloodandrainfallintensity.Contingencyresponseplans,conditionmonitoringandearlywarningsystemsareinplace.Thereissomeduplicationofcommunicationssystemsandbackupgenerators.
Climate Change Action 7 – Reviewing design specifications of existing critical infrastructure
Corporate Sustainability key focus Area: Reliable waterAforwardprogramforthereviewofdesignspecificationsofexistinginfrastructure,plantandequipmentwillbedevelopedtoassessvulnerabilitytoextremeeventssuchasstorms,firesandfloods.Scenariotestingofcriticalinfrastructure,vulnerabilityassessmentandincreasingredundancyatcriticalsiteswillalsobeundertakenwhereappropriate.Detailedmodellingofdemand/supplyoptionsandfurthermodellingofprobablemaximumfloodswillbeconsideredtoassistinplanningupgradesorchangestooperatingregimessuchaspre-releaseinadvanceofaflood.
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5.7 Supply chain
Key vulnerabilities• Inabilitytosupplysufficientwatertocustomersasperagreements.• Inabilitytomeetwaterqualityparametersinwatersupplyagreements–
impactonfiltrationplants,publichealth,customerconfidenceandcomplaints.
• Changesincustomerdemandduetochangesinpopulationdistributionandconsumption(seealsoWaterQuantity).
• Increasedelectricitycostsimpactupstreamanddownstreambusinesses.• Decreasedreliabilityofelectricitysupply(moreblackouts)impactabilityto
transferwater.
ChangesinclimaticconditionsandgovernmentpressuretoreducecarbonemissionsarelikelytohaveupstreamanddownstreamimpactsontheSCA,intermsofsuppliersofgoodsandservicestotheSCAaswellasthedeliveryofwatertoitscustomers.SomeofthesechangeswillcreatenewormodifiedriskstotheSCAwhileotherswillpresentopportunities.
Torespondtothesechallengesandopportunities,theSCAwillneedtofurtherutiliseorexpanditsexistingrangeofoperatingprotocolsandformalandinformalprocessesforregularcommunicationwithcustomers,suppliersandotherstakeholders,liaisonthroughgovernmentnetworks,flexiblewatertransferandconfiguration,MWPforecasting,andincidentmanagement.
TheabilityoftheSCAtosupplywaterthroughgravityfeedandtheuseofback-upgeneratorsforcontrolsystemsinsulatestheSCAfromelectricitydisruptionstosomedegree,butthereisaneedtoexpandtheuseofstand-aloneelectricitygenerationandre-engineersomekeysystemsformanual/analoguecontrol.
Increasedfrequencyandseverityofstormsandextremeeventscouldpotentiallydisruptservicedeliveryofcriticalitemssuchasdieselfuel,powersuppliesandsubsequentlyotherservices.Thereisaneedtoimproveunderstandingofsupplychainvulnerabilities.
Anincreasedemphasisontheformalassessmentofvulnerabilityofgoodsandserviceproviderstoenergydisruptionsandotheroutages/unavailabilityofcriticalrequirementswouldbebeneficialinresponsetoclimatechangeaswellasotherexternalforcesoutsideoftheSCA’sdirectcontrolsuchaspopulationgrowthanddistribution.
5.8 Business
Key vulnerabilities• Difficultyinmatchingsupplytodemand.• Lossofsalesquantitywithresultantchangestorevenue,expenditure,
dividendsandfinancecosts.• DecreasedpublicconfidenceinSCAtodeliverreliablequalitywater.• Increaseindisruptionandnumberofdeclaredincidents(egfloods,
declareddroughts,algalblooms);concurrentincidents.• Decisionsupporttoolsarenotabletopredictclimatechangeimpactson
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futureplansandoptions.• Communicationsystems,SCADAcompromised(seealsoInfrastructure).• Businessinvestmentsaresub-optimalunderachangedclimate.
Climatechangehasarangeofimplicationsonrevenuefromwatersales,capitalexpenditureandpumpingcosts,aswellasoncompetitionfromalternativewatersourcessuchasdesalination.Impactsonsupplyandwaterqualitywillincreasetheneedtojustifyexpenditureandputpressureonrevenues,withflow-oneffectstoSCA’snegotiationswithregulatorsandratingsagencies.
Variabilityinsystemyieldcouldbeoffsetbyalternativefinancialinstrumentsandforwardsalescontractstomanagepricerisk.
Financialimpactscouldbemitigatedbymoresophisticatedeconomicmodelling,alternativefinanceoptionssuchasinsuranceforunanticipatedpumpingcostsandalternatebusinessmodelstoenablegreaterdiversificationandflexibilityinsupply.Thereisaneedtoimproveincidentmanagementcapability,businesscontinuityplans,workforceadaptivecapacityandmulti-skillingofstaffforworkplaceflexibility.TheSCAmightalsoconsiderexpandingitsroleinthedeliveryofalternate(outofcatchment)watersupplyschemes.
Climatechangeimpactsonwatersupplyandwaterqualitywillincreasetheneedtojustifyprojectdesignandexpenditure.Businesscasesfornewprojectproposalscurrentlyincludesustainabilitycriteria,butnotclimaticassumptionsorsensitivities.
Climate Change Action 8 – Building explicit consideration of climate change into new business initiatives and project designs
Corporate Sustainability key focus area: Business viabilityEnhancedworkforceflexibilityandorganisationalresiliencewillbedeveloped.Incidentresponseplanswillbeexpandedtoaddressabroaderrangeofscenariosandthedisruptiverisksthroughimprovedcontinuityanddisasterrecoveryplanning.Attentiontoincidentmanagement,businesscontinuitymanagementanddisasterrecoveryplanningwillbeincreased.Otherresponseoptionswillbeexploredincludingforwardsalescontractsandalternativefinancialinstrumentstomanagepriceandsupplyrisk,improvingworkforceadaptivecapacityandresponsivenessthroughup-skillingandculturalchange.
InthefutureallSCAbusinesscases,whicharealreadyrequiredtoincludesustainabilitycriteria,willberequiredtoaddressclimaterelatedrisksanddemonstratetheirpotentialtoimprovebusinessresilience.Businesscaseswillalsoexplorealternativefundingoptionsandeconomicmodels.
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AchangeinclimatewouldhavefundamentalimplicationsforSCAbusiness,affectingsales,competition,customersatisfactionandcommunityconfidence.Climatechangeisbecomingincreasinglyreflectedingovernmentpolicywithresultantimpactsoncarbonpricing,renewableenergytargetsandelectricityandfuelcosts.Improvedmodellingoftheimpactofclimatescenariosandclosecollaborationwithexternalagenciesandongoingreviewofadaptationplansisessential.
Highertemperatureandmoreseverestormswouldlikelyleadtoanincreaseinthenumberandcomplexityofdeclaredincidents.Concurrentincidentsorcascadingfailuresofkeyinfrastructurewouldchallengeoperatingproceduresandorganisationalresilience.
Increasedattentiontoclimatechangeinsupplyplanning,systemmodelling,IndependantPricingandRegulatoryTribunal(IPART)negotiations,CorporateSustainabilityStrategy,businesscontinuitymanagementanddisasterrecoveryplansiswarranted.
Climate Change Action 9 – Increasing preparedness to manage concurrent incidents
Corporate Sustainability key focus area: Business viabilityWhiletheSCA’sincidentresponseandscenariobasedcontingencyplanningarereasonablycomprehensive,increasedattentionwillbepaidtoincidentmanagement,businesscontinuityanddisasterrecoveryplanning.Thiswillalsoconsiderthepotentialforimprovedworkforceadaptivecapacityandresponsivenessthroughupskillingandculturalexchange.
Key vulnerabilities• Unabletomeetcustomerdemandduetoreducedinflowstostorages.• ChangeinfunctionandownershipoftheSCA.• DECCW–changestotheSpecialAreasStrategicPlanofManagement
(SASPoM),bushfiremanagement,licensedpollutercompliance,climatescienceprogram,openorclosedcatchments.
• Regulators(IPARTandothers)–increasedpressuretoquantifyimpactsandjustifyexpenditureonclimateimpacts.
• DepartmentofHealth-revisionstoAustralianDrinkingWaterGuidelines;WaterQualityCharacteristics.
Changesinsecurityofsupply,watersourcemanagementandwaterqualityresultingfromclimatechangecouldimpactonpublicconfidenceintheSCA’sabilitytodeliverreliablequalitywater.AninabilitytomeetwaterqualityparameterscouldimpactonpublicconfidenceintheSCA’sabilitytodeliverreliablequalitywater.Longerdroughtperiods,elevatedtemperaturesandsporadicperiodsofheavyraincouldresultinbreachesofsupplyagreementswithcustomers,requiringre-negotiationandamendmentstorelevantlegislationandsupplyagreements.Longerterm,climatechange
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impactsonwaterqualitycouldbelessofaproblemthanquantity,becauseawiderrangeofcontrolmeasures(sourceandofftakeselection)andtheabilityofcustomerstoupgradetreatmentplants.Impactsonsupplyandwaterqualitywillincreasetheneedtojustifyexpenditureandputpressureonrevenues,whichinturnwillflowthroughtoSCA’snegotiationswithregulatorsandratingsagencies.
SCAhasstrongrelationshipswithstakeholdersandregulators,atbothpolicyandoperationallevels.TheWaterforLifeprogram,coordinatedbetweenSydneyWater,theSCA,theNSWOfficeofWaterandDECCW,provideseffectivepublicoutreach,butcouldbemoreproactiveineducatingthepubliconalternativewatersourcesthatmaybeconsideredinthefuture.TheSCAworkscloselywithIndustry&InvestmentNSWwithitsruralandgrazingoutreachprograms.
ThelegislativeandregulatoryframeworksthatdefineexpectationsoftheSCAarebasedonhistoricallyachievablevaluesofwaterquantityandqualitysuppliedfromSydney’sdrinkingwatercatchmentsandreservoirs.Climatechangewillincreasinglyinfluencerelationshipswithexternalagencies,inparticularDECCWthroughitsCCAP,publiclandsmanagementandscienceprograms.NSWHealthwillcontinuetoplayakeyroleinrevisionstotheAustralianDrinkingWaterGuidelinesandemerginghealthrisks.
Climate Change Action 10 – Improving communication and knowledge exchange on climate change
Corporate Sustainability key focus area: Industry ExcellenceNeworexpandedoutreachprogramswillbedevelopedtomanagecommunityexpectationsofwaterqualityandsupplyissues.Atthesametimeadaptationstoclimatechangewillbeincludedincatchmentdevelopmentcontrolsandbestmanagementpractices.Thoseresponsiblefortheirimplementation,suchaslocalcouncilsandlandholders,willbekeptinformedandassistedtoadjusttheiractivitiesanddecisionsinresponsetoclimatechangeimpacts.
ToavoidtheimpactofclimatechangeoncatchmentcommunitiesandlandownersputtingadditionalpressureontheSCA’sroleinplanning,incentivesandcompliance,toolssuchasCDSS,NorBE,SLWCA,stormwaterandonsitewastesystemmodelswillberegularlyupgradedtoreflectchangingormorevariableclimate.EducationandoutreachprogramsandcloseliaisonwithlocalgovernmentandtheDepartmentofPlanningwilldrivetherequiredchanges.
Pre-treatmentathigh-risksitesandre-negotiationoftheacceptablerangeofwaterqualityparameterswithwaterfiltrationplantoperatorswillbeexploredaspossibleresponseoptions.Opportunitiesforpubliceducationandoutreachonrelativehealthrisksofdifferentwatersources,themanagementofcommunityexpectationsandimprovedpublicpreparednessforpossiblewaterqualityincidentswillbeexplored.
6 ConclusionTheclimatechangeimpactassessmentconductedbytheSCAin2010foundthatoverall,theSCAhasahighdegreeofpreparednessforaddressingmanyofthepotentialimpactsofclimatechange.
TheclimatefuturesusedinthisassessmentwerebasedonrecentclimateprojectionscoveringSCAcatchmentareas,andinvolvedtwofutureclimatescenarioswithhighertemperaturesandmorevariablerainfall.Theassessmentemphasisedthecomplexityoftheinterrelationsbetweenwaterquantity,waterqualityandcatchmentcondition,andhighlightedthepotentialimpactsofclimatechangeonSCAoperations,infrastructure,businessandregulation.
TheassessmentidentifiedandprioritisedpotentialclimatechangeimpactsontheSCA,identifiedcurrentactivitiesorcontrolsthatpartiallymitigatetheimpacts,anddevelopedarangeofresponsesthatcouldbeconsideredinthefuture.Theseresponsesincludeidentifyinganumberofbusinessareaswhereimprovedplanning,additionalinvestmentandback-upsystemscouldassistinbuildingtheSCA’sadaptivecapacityandbusinessresilience.
ThefindingsofthisclimatechangeimpactassessmenthavebeenbuiltintotheSCA’sbusinessplanningaspartoftheCorporateSustainabilityStrategythatprovidestheSCA’sstrategicdirectionforthenextfiveyears.
Projectionsoffutureclimatehavelargeuncertaintiesbecausecurrentmodelsareunabletocapturethecomplexityoffeedbackmechanismsintheearth-atmosphere-hydrospheresystem.Althoughthescienceofclimatemodellingisrapidlyimproving,modelsandprojectionsatbestpresentarangeofpossiblefuturestoconsiderinscenarioandbusinessplanning.SuchknownuncertaintyrequirestheSCAtobeadaptabletorapidchangeandapplyongoingsustainableandflexiblebusinesspracticestoensureresiliencetochangesinclimateandotherexternalforces.
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References
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AcronymsARR AustralianRainfallandRunoff
CCAP ClimateChangeActionPlan
CMA CatchmentManagementAuthority
CRP CurrentRecommendedPractices
CDSS SCA’sCatchmentDecisionSupportSystem
CSIRO CommonwealthScientificandIndustrialResearch Organisation
DECCW DepartmentofEnvironment,ClimateChangeandWater
ENSO ElNiñoSouthernOscillation
IPART IndependentPricingandRegulatoryTribunal
IPCC IntergovernmentalPanelonClimateChange
MWP MetropolitanWaterPlan
NorBE Neutralorbeneficialeffectonwater
PMF ProbableMaximumFlood
SAM SouthernAnnualMode
SASPoM SpecialAreasStrategicPlanofManagement
SCA SydneyCatchmentAuthority
SCARMS SCA’sReservoirManagementSystem
SEPP StateEnvironmentalPlanningPolicy(SydneyDrinking WaterCatchment)2011
SLWCA StrategicLandandWaterCapabilityAssessment
STP Sewagetreatmentplant
WQRA WaterQualityResearchAustralia
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Contact informationSydneyCatchmentAuthorityPenrithOfficeSydneyCatchmentAuthorityLevel4,2-6StationStreetPenrithNSW2750
Telephone +61247242200 1300SCAGOV(1300722468)
Fax +61247252599
Officehours 8.30amto5pmMondaytoFriday
Website www.sca.nsw.gov.au
Email [email protected]
©SydneyCatchmentAuthority
©StateofNewSouthWalesthroughtheSydneyCatchmentAuthority,2010.Thisworkmaybefreelyreproducedanddistributedformostpurposes,howeversomerestrictionsapply.Seethecopyrightnoticeonwww.sca.nsw.gov.auorcontacttheSCAon1300722468.
ISBN978-1-876951-52-8