RiversTrustCaBAWorkshop,London,26.6.2017
ManagingAbstrac-oninSensi-veRivers
BenefitsofEvidence,BadgeringandCollabora-on
JohnLawson,FREng,FICE,FCIWEMWaterResourcesAdviserto
Ac-onfortheRiverKennetandtheWye&UskFounda-on
WhatIwillcover• Contras>ngexperiencesfromtheRiverKennetandtheRiversWye&Usk
• Theneedforbadgeringandpersistence
• Theimportanceofevidence
• Thebenefitsofcollabora>on
TheKennetSaga
Oxford
Reading
London R. Kennet
R. Thames
R. Thames R. Og
Upper Kennet Boreholes
Farmoor Reservoir
GATOX Pipeline
Sewage return to Thames
Swindon
Axford
Ramsbury
Ogbourne Clatford
Marlborough
Upper Kennet Abstraction: 15 Ml/d export to Swindon, 4 Ml/d local supply
15 Ml/d export to South Swindon
ARK’slong-runningconcerns
• Flowsunacceptablyreducedindryyears
• Abstrac>oniscausingtheriveraboveMarlboroughtodryupforlonger
• Abstrac>oniscausingtheRiverOgtodryaltogetherindryyears
Thisallaffectsriverinsects,plantsandfish
Keydatesinthesaga• 1990 ARKformed
• 1990-2000ARKbadgering,liRleprogress
• 2000-2012VariouslowflowstudiesbyTW,EAand ARK.Nocollabora>on
• 2012 KennetCatchmentPartnershipformed
• 2012 EA/TWagreementonnewpipeline fundingandcessa>onofOgbourne abstrac>on
• 2017 New£25mpipelinecommissioned
The“Axfordsolu-on”• 10kmpipeline,500mmdia,cos>ng£25million
• Connec>ngFarmoorreservoirtoSouthSwindon
• Axfordpumpingreduced11Ml/dto6Ml/d,BUTonlywhenriverflow<100Ml/d
• Ogbournepumpingstopped(typically4Ml/d)
New 500 mm water main
Existing main from Farmoor reservoir
Existing Axford boreholes
Existing Ogbourne boreholes
Existing supply to S. Swindon
M4
GWR
ARK’scon-nuingconcerns1. TheriverflowtriggerforAxfordreduc>onis
settoolow–thereduc>onoccurstoolatetoproviderelief
2. LiRlebenefitfromthe£25millioninvestmentinthenewpipeline
3. Theimpactsofabstrac>onaboveMarlboroughares>llnotbeingaddressed
LimitedbenefitsfromTW’s£25millionscheme
Boreholes still affecting
upper river
Exports to Swindon continue at most times
Wessex b/hs?
DryKennetatMarlborough,Sep2011
TheAxfordandOgbournereduc-onswilldonothingtohelpthis
ARKEvidenceGathering
Ourowninves>ga>onofflowimpacts-S>llnotdiscussedwithEAandTW
Whatwewouldliketohappen• Completecessa>onofexportsofKennetwatertoSwindon
• Axfordtobeusedonlyforlocalsupplies,includingMarlboroughandabove
• MarlboroughandClabordboreholestobeusedonlyinemergencies
ARK’sproposalforachievingthishasbeenrejectedbyThamesWaterWhy not use the £25 million pipeline
investment all the year round?
Wherearewenow?• Aeer27yearsandnorealcollabora>on
– Noagreementonhowtousethe£25millionasset– NoagreementonflowsaboveMarlborough
• BUT,encouragingrecentwordstoARKfromTW’snewCEO:“thenewpipelineisjustthefirststep”“togetherwe’llfindsolu>ons”
TheWye&Usksuccessstory
Cardiff
Brecon Hereford
Usk
Usk
Crai Talybont
Llandegfedd
R Wye
TheWye/UskWaterSupplySystemElan valley reservoirs Elan valley aqueduct
supplying 360 Ml/d to Birmingham
Releases from Elan valley to regulate flows in Wye
Upper Usk dams supplying about 55 Ml/d to Swansea area
Releases from Usk dam to support drought flows
Lower Usk 175 Ml/d to Cardiff and Newport
Wye/Usk transfer 125 Ml/d Monmouth
Total all abstraction c 900 Ml/d
Builth Wells
Supplying 3 million people
Canal
Impactsonsalmon
WUF’s concerns: • Major flow regime changes since 1970s
• Much less reservoir spillage
• Big fall in salmon numbers since 1970s
• Salmon stuck in lower rivers
• Uncontrolled canal abstraction
Original2004-10proposalsforHabitatsDirec-veCompliance
• FocusedonachievingHD“EcologicalRiverFlows”
• Used“benchmarkflows”,iedamsarenatural!
• Didn’treduceimpactsofdamsonspates
• Didn’tachievenaturalflowvaria>ons
• Hadbigimpactoncanalwatersupplies,probablyrequiringcanalclosure
BUT,compliedwith“rules”,sodeemedOK!
WUFWhingeing&Badgering
• From2007to2010,wewroteleRers,hadmee>ngs,madeFoIrequests
• Andgotnowhere!
NRWresponsetoWUFWhingeing
• We’vecompliedwith“therules”• Ourmodellingshowsit’sOK• It’sbeenagreedbyeveryone• It’stoolatetochange
WUFEvidenceGathering
Our own investigation to break the impasse - Evidence gathering and counter-proposals
WUFtoolsforgenera-ngevidence
• Wholeriversalmoncatchanalysis
• Individualbeatcatchanalysis• Modellingofwatersupplies,riverflows,watertemperatureandsalmonmigra>on
Genera>ngevidence-basedcounter-proposals
WUF’sproposedsolu-on
• Makemoreuseofthereservoirstosupportriverflowsandecology
• Especiallyinnon-droughtyears
• Majorimprovementwithnoimpactonwatersupplies
Mid-2012:Forma-onofUsk&WyeAbstrac-onGroup(UWAG)
WelshWater,SevernTrent,NRW,EA,CRTandWUF
Workingtogetherto:• maximiseecologicalbenefits• minimiseimpactsonwatersupplies• improveopera>onratherthancutsupplies• makebeReruseofreservoirstohelpfish
KeyplayersinUWAG
Gail Davies, Welsh Water Owain Sheppard, NRW
Supported by Cascade Consulting (now Ricardo)
UWAGcollabora-on• 4workinggroups–strategic,technical,modelling,fisheries
• 36workinggroupmee>ngsin2years
• Freesharingofdataanddraepapers• Sharingandharmonisa>onofmodels
• Numerousdiscussionpapers,proposalsandcounter-proposals,leadingto:
UWAGAgreementofDecember2014
TheUWAGAgreement
Signed by affected parties, supported by NRW & EA
SummaryofImprovementsExceptinseveredroughts,usereservoirstorageto:• Makereleasesfromdamstoboostexis>ngspates
• Delayswitch-offofregula>onfor7daysaeerstartofspates
• AvoidsummerpumpingtorefilllowerUskreservoir
• Increasecompensa>onflowstomirrornaturalflows
• UseUskreservoirtosupportBrecon&Monmouthcanalsuppliesindroughts
Benefitsofimprovements
• Flowsclosetonaturalflowsatcri>cal>mes• MuchbeRerflowsforspawningandjuveniles• Muchreducedsalmonmigra>onimpacts• Canalopera>onsecuredinmostdroughtsNoaddi>onalimpactonpublicwatersupplies
LowsummerflowinthelowerUsk
Stranded ranunculus from diurnal pumping variation
Withnatural
riverflows
WithUWAG
proposals DiffToendJune
ToendSep
ToendDec
5445 4093 1352 24.7% 24.8% 10.5%
SalmonmigrationtoendSep %losses
Flow reduced by c.40%
Salmon migration to end September reduced by 1350
Much reduced pumping in migration season
1100 more salmon in river by end Sep With
naturalriverflows
WithUWAG
proposals DiffToendJune
ToendSep
ToendDec
5445 5175 270 4.1% 5.0% 2.4%
SalmonmigrationtoendSep %losses
Recentprogress• Draeingnewlicencesandopera>ngmanuals
• Newpumpingsta>on,reservoiroutletvalvesandtelemetrydesigned(forAMP6installa>onby2020)
• Collabora>ononreal->meopera>on
• Benefitstoflowsandfishalreadyevident
Collaboration works!
Whatwe’velearnedfromtwoverydifferentexperiences
• Whingeingwithoutnewevidencedoesn’twork
• Badgeringwithnewevidencecanchangeminds
• Genera>onofnewevidenceandproposalsthroughcollabora>onworksbest
• LiRlegetsachievedwithoutmutualunderstandingofconcernsandgoals