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Spring 2021 Our Drought Plan Summary 2021 Summary Our draft Drought Plan 2021: supply in adrought your waterManaging
2 Our Drought Plan Summary 2021 Thames Valley. 10 millionhouseholdcustomersand215,000businessesinLondon andacrossthe businesses. It’sourjobtoprovideareliablesupply of safe drinkingwater toaround associated withwater-use, suchascar washes,brewers, andhairdressers,butall hospitals, andservicessuchastheFireService.Andfor businessestoo–notjustthose activities suchaswashing,cooking,andrecreation.It’salsovital for runningschools, Water isessentialfor allourlives. Every daywe usewater for drinkingandroutine other sources. of water aswell astaking morefrom theenvironmentand customers’ drinkingwater supplyby usingadditionalsources households andbusinesses;howwe’d maintain reduce theirwater use;therestrictionswe’d placeon customers aboutadrought;howwe’d workwithcustomersto when we wouldtake them.Itoutlineswhatwe’d dotoinform Our DroughtPlansetsouttheactionswe wouldtake, and environment. provide essentialsuppliesofwater, whileprotecting the depleted, andwe mayneedtotake actionstocontinue periods oflowrainfall ourwater suppliescan become However, we can’t planfor alleventualities. Duringextended of dryweather andtake intoaccountchangestoourclimate. sustainable supplyofwater toourcustomersduringperiods We planaheadtomake surewe can provideasecureand You can find ourfull draft Drought Planhere:thameswater.co.uk/droughtplan. Page 8 Page 7 Page 6 Page 5 Page 4 In itwe explain: This documentisasummaryofourdraft Drought Plan 2021. We are updating ourDrought Plan Actions we’ll take inadrought What happensinadrought? How dowe knowwhenadroughtisdeveloping? Your water supplyandhow itcouldbeaffected inadrought What isadrought? water supplyto2100. to provideasecureandsustainable resources toensurewe can continue investment thatisneeded innew change anditsetsoutthesignificant growth andtheimpactsofclimate challenges includingpopulation Plan 2019considersfuture Our Water Resources Management
3 Our Drought Plan Summary 2021 How we develop ourDrought Plan (Defra) on1April2021. We submitted ourdraft DroughtPlantotheSecretary ofState Our lastDroughtPlanwaspublishedin2020. Once approved, we’ll publishourfinal DroughtPlan. We’ll sendtheupdated draft Plan toDefra for approval. of Response, andupdate ourdraft Plan. We’ll review feedback totheconsultation, produceaStatement following approval from Defra. We’ll holdapublicconsultation onourdraft Plan.Thiswillstart companies intheSouthEast. We’ve consulted stakeholders andworked closelywithother guidelines, andupdated information onoursupplyschemes. We’ve refreshed ourPlan,taking accountofrevised government • Here isasummaryofthemainchangestoourDroughtPlan: What’s new? • • • • droughts thanwe’ve experiencedinthepast. We’ve tested ourPlantounderstand howwe can copeinmoresevere such asmobiledesalinationplants. reductions inwater useandtheofadditionalemergencywater sources referred toas‘MoreBefore Level 4measures’,theseincludesignificant We’ve developed additionalmeasuresfor themostseriousdroughts, scheme, asitisnolongeroperational. (the desalinationplant)to100Ml/dandremoved theHoddesdontransfer that can besuppliedby theThamesGateway Water Treatment Works Based onanupdated assessment,we’ve reducedtheamountofwater aligning anyexemptionsthatmaybeapplied. companies intheSouthEast if water userestrictionsareneeded,including We’ve agreedtotake acoordinated approachwiththeotherwater other water companiesintheSouthEast. (see page8)willnowbeimplemented atthesametimeasappliedby the need toapplywater userestrictions.Temporary UseBan(TUB)restrictions We’ve updated ourlevels ofservice–thefrequency thatwe expectto 4 Our Drought Plan Summary 2021 growing season,whereas adroughtthat affects public water supplycan take manymonths ofbelow average rainfall. Droughts can affect different water usersin different ways and happenatvarying times. For farmers, adroughtcan occurafter just afew weeks ofdryandsunnyweather duringthe rainfall isreallyimportant, asitrefills thenatural undergroundaquifers thatfill upthe rainfall throughouttheyear tomake surewe alwayshave enoughwater. Winter by afew dryweeks, andthey can’t besolved by afew wet ones.We needregular A droughtisaprolongedperiodofabnormallylowrainfall. Droughtsaren’tcaused Istanbul, Sydney, orBarcelona. people thinkwe have plentyofrain, butitactuallyrains lessinLondon thanin The water we usefor publicwater supplyreliesontheweather, specifically rain. Most What isadrought? groundwater ground andmaintains our Rainfall percolates intothe aquifers thatmaintains theflowofrivers During periodsoflowrainfall, it’sthe flow ofwater from The aquifers feed ourrivers and helpkeep themflowing. percolated intotheground – rainfall thathasn’t comes from surface run-off Water flowinrivers also rivers We abstract water from The diagram below explains why suchweather patterns cause problems. below average rainfall. Thelastmajordroughtinoursupplyareawas1975-76. affects. Inourarea,theworstdroughtshave followed twoconsecutive winters of Every droughtdiffers interms ofhowlongitlasts,intense itisandtheareas very littleavailable torechargegroundwater sources.. rivers. Summerrain islargelyusedupby plantsandlostthroughevaporation leaving boreholes groundwater using We abstract treatment plants groundwater to We pumptheabstracted Rivers rainfall inwinter thentheaquifers arenotrefilled bearing rockscalled aquifers. Ifthere’snotenough Groundwater isstorednaturally inlayers ofwater- plants. we pumpittotreatment raw-water reservoirs before We storewater inlarge,open Your water supply and how it could be affected in a drought Your water comes from rivers and groundwater and is either stored in large reservoirs zones. A drought can affect each zone differently, depending on where the water until needed or treated and put directly into supply. The water is always treated to a comes from and how those sources respond to different types of droughts. This is high standard before it reaches your tap. why during a drought one area may have different usage restrictions to another.
Thames Water’s supply area is divided into six water resource zones: London; The map shows our water supply area, the water resource zones and the main Swindon and Oxfordshire; Kennet Valley; Guildford; Slough, Wycombe and Aylesbury; sources of water in each zone. and Henley. Water can be moved around in each zone and, in some cases, between