Energy at any price? - Gwent Wildlife Trust

26平 成 27 年4 月 19 日日 立 市 東 成 沢 町 3 丁 目 7 番 7 号会 社 員無 所 属しゅんいちあおき 俊 一男昭 和 29 年8 月 24 日(60 歳 )本 人 届 出27平 成 27 年4 月 19 日日 立 市 諏 訪 町 5 丁 目 1 番 9 号白 山 代 表無 所 属せんざぶろうしらと 仙 三 郎男昭 和 21 年2 月 22 日(69 歳 )本 人 届 出28平 成 27 年4 月 19 日日 立 市 弁 天 町 3 丁 目 4 番 19 号日 立 市 議 会 議 員日 本 共 産 党こばやしこ小 林 まみ 子http://www.jcp-net.jp/ibahoku/女昭 和 39 年3 月 26 日(51 歳 )本 人 届 出29平 成 27 年4 月 19 日日 立 市 高 鈴 町 2 丁 目 5 番 10 号政 党 役 員公 明 党しもやまだ下 山 田 みきこhttp://www.komei.or.jp/km/simomiki/女昭 和 34 年6 月 19 日(55 歳 )本 人 届 出30平 成 27 年4 月 19 日日 立 市 久 慈 町 3 丁 目 6 番 9 号久 慈 町 漁 業 協 同 組合 顧 問無 所 属けんいちとびた 謙 一男昭 和 24 年12 月 25 日(65 歳 )本 人 届 出31平 成 27 年4 月 19 日日 立 市 水 木 町 2 丁 目 32 番 7 号日 立 金 属 株 式 会 社社 員無 所 属ひろみおおば 弘 美男昭 和 31 年8 月 24 日(58 歳 )本 人 届 出32平 成 27 年4 月 19 日日 立 市 石 名 坂 町 2 丁 目 17 番 2 号 無 職無 所 属かずやまつざき 和 也男昭 和 63 年8 月 9 日(26 歳 )本 人 届 出4 / 4

AT RISKAbout 80 times a yearthe incoming tide andthe Estuary’s funnelshape create theSevern Bore – and thechance to surf formiles in fresh waterThe BoreThe Estuary is exceptional for fishing and birdwatching. And theSevern Bore is one of the UK’s greatest natural phenomenaAndrew MawbyDavid ChapmanMike LaneDavid WoodfallPREVIOUS PAGEAs dawn breaks overGloucestershire a strange sceneunfolds in a pub car park. Thisis Arlingham on the banks ofthe Severn, but it is a sight morecommonly associated with the beaches ofDevon and Cornwall. Men and women aredonning wetsuits, waxing their surfboards andentering the waters of the river.The opposite bank is already thronged withpeople holding video cameras and binoculars.Everyone is gazing downstream, straining tobe the first to glimpse the oncoming tide. Butit’s their ears that sense it first. Initially a dullrumble, the sound intensifies until by the timethe Severn Bore is visible, rounding the finalbend, it sounds like an approaching train.The surfers clamber onto their boards. Forsome, it will be the longest ride of their lives; afew have managed over six miles. Thespectators are about to witness one of the UK’smost spectacular natural phenomena.The Bore is born in the funnel-shaped,strongly tidal Estuary. The massive incomingtide is squeezed into a smaller and smallerspace until the water has no choice but to pileup, forming a wave that travels upstream formore than 30 miles, at speeds of up to 15mph.Over the ages the Bore has become part ofthe river’s ecosystem. But it’s also important topeople. Many businesses benefit from thetourism the Bore creates, whilst salmon andelver fishermen rely on it for their livelihood.The Bore is also incredibly important to thesurfers that ride it. As well as the hundreds ofcoastal surfers who come for the largest tidesthere is a tight-knit group who organise theirlives around the lunar cycle, so that they canbe in the river the next time the Bore roundsthat bend. But a device that reduces the river’stidal range would eliminate all that.Dave Butterton, Bore surferThe Estuary provides many forms of recreation. Itslandscape brings walkers and sightseers from allover Wales, the South West and the MidlandsIt’s quite possible to spend a lifetime birdwatchingin the Estuary (see page 14). Hundreds of species,some from half way round the world, pass throughMore than 100 species of fish are found in the riverSevern and its Estuary. Some of the most soughtafterspecies migrate into its eight tributary riversNEXT PAGE8 The Wildlife Trusts’ Severn Estuary reportThe Wildlife Trusts’ Severn Estuary report 9

AT RISKLike many visitingwaders, knot gatherin the Estuary inhuge flocksRefuge for birdsPREVIOUS PAGEThey arrive by the thousand, from Canada, Africa and Russia.And they come to the Estuary for food, rest and shelterIhave watched birds on theGloucestershire sector of the SevernEstuary since I was ten, when I made the50-mile round trip by bicycle everyweekend. Some early highlights arousefond memories: that snow bunting in October1953, or the red-throated diver at high tide inJanuary 1956. But it’s the regular visitorswhich leave the lasting impression.For example, Slimbridge is a winter refugefor white-fronted geese and thousands ofwigeon, teal and pintail, which migrate everyyear from Russian breeding grounds to theterminus at the westernmost end of their3,000 mile flyway. In the cold winter of 1962they were joined by a massive arrival ofRussian Bewick’s swans, which havecontinued to come ever since, though like thewhitefronts their numbers have decreased.The Severn is also an essential refuellingstop for long distance migrants that winter insub-Saharan Africa and pass through the UKtwice: in spring, on their way to Arcticbreeding grounds in Canada and the Russiantundra; then again in early autumn on theirway back. Waders like bar-tailed godwit orlittle stint use the short tundra summer tohatch their young; within a few days the adultsleave, arriving on the Severn in late July orAugust before moving on to places such as theBanc d’Aguin in Mauritania, or even SouthAfrica. Their young find their own way amonth or so later.Quite apart from the navigational feat, thephysiological performance is exceptional; bothyoung and adults put on half their bodyweight in fat to enable them to make theseThe adults leave their young inthe Arctic, arriving on the Severnin July before moving on to Africaflights. They use up this extra fat in migration,so stops in biologically rich estuaries are vital.Then, having wintered in warmer climes, theyare back on the Estuary the following spring,together with other waders like whimbrelwhich gather in the western UK to refuel, enroute to their Icelandic nesting grounds.In cold snaps the Estuary’s brackish waterremains ice free, attracting birds from inlandsites like the Somerset Levels or the SevernVale. Waders such as lapwing or goldenplover, together with ducks from riversidemarshes, flock to the Estuary at these times.In every way, then, the Severn Estuary is abird site for all seasons.Mike Smart, TrusteeGloucestershire Wildlife TrustBesides the huge flocks,the rarities. This is apomarine skua, pausinghalf way between the farNorth and the tropicsDavid SlaterNEXT PAGE14 The Wildlife Trusts’ Severn Estuary reportThe Wildlife Trusts’ Severn Estuary report 15

How the Estuaryecosystem worksIt all begins with washed-in organic debris.Then the mud dwellers get to workThe Severn Estuary is a hugely productiveplace, but that productivity isn’t driven directlyby green plants and the sun. Instead theEstuary acts like a gigantic reprocessing plant,using as its raw material plankton and flotsamwashed in from the sea and tributary rivers,plus churned-up sand-dwelling microscopicplants. In the mud and silt of the intertidalzone (between high and low tide), billions ofinvertebrates and bacteria convert this debrisinto protein.With fast, silt-laden currents in the centralchannel, most of the predation happens in theintertidal zone. The fish grab the worms andshellfish at high tide, with the prawns andcrustaceans hoovering up the bits; six hourslater it’s the birds’ turn.Most of the Estuary’s ecology happens inthe intertidal zone. Reduce its extent, and youlose most of that huge productivity, withknock-on effects to ecosystems elsewhere.Overleaf shows where they are.The humble lugworm.Estuary mud and sandcontains relatively fewspecies, but in huge numbersVital statistics of the Estuary ecosystem10,000,00069,00024,70020,9585,0001,5001,400100+10estimated tonnes of sediment carried upand down the Estuary on a spring tidevisiting birds, either sheltering from the Arctic winter or refuelling duringtheir spring/autumn migration between north and south hemisphereshectares of the Severn Estuary in total,making it one of the largest in Europehectares of mud and sand flats –the fourth largest expanse in the UKyears of sedimentation evidence in the Estuary – avaluable geomorphological and archaeological historyhectares of rock, boulder, mussel/cobble scars,rocky pools and shinglehectares of salt marsh –the largest expanse in the South Westspecies of fish foundin the Estuaryspecies of commercial fish use the Estuary in their life cycle: herring, cod,plaice, sole, whiting, blue whiting, hake, horse mackerel, ling and saitheDavid ChapmanZONESCHARACTERISTICSLarge tidal rangeHABITATSSaltmarshWILDLIFEFishPREVIOUS PAGEEXPOSED INTERTidalSUBMERGEDThe key feeding zone: birdsat low tide, fish at high tideThe silty water looks lifeless but,as this salmon trap shows, is acorridor and food supplyDavid Woodfall David WoodfallLarge intertidal areaLots of suspendedmaterialNutrient richStrong currentsHighly productivehabitatsSandbanksMudflats rich in wildlifeRock and shingleshoreline habitatsLow and high salinitywaterShallow sandbanksSilt laden currentsMuddy seabed rich inwildlifeShallow water-churnedseabedNeil HepworthPlant planktonRick ParkSand-dwellingwormsDavid ChapmanShellfishAlgal andplant communitiesDavid SlaterMid-waterfishPaul NaylorAnimal planktonRick ParkBirdsDavidSlaterSand-dwellingdiatomsSea mammalsFlorian GranerNature PLAnson MacKayPaul NaylorBottom-dwellingfishHans HillewaertSand-dwellinginvertebratesPaul HobsonCrustaceansPaul NaylorOtherinvertebratesDavid ChapmanTURN THEPAGE FOR THEMAIN EFFECTSON OTHERECOSYSTEMSNEXT PAGE16 The Wildlife Trusts’ Severn Estuary reportThe Wildlife Trusts’ Severn Estuary report 17

iStock PhotoThe global impactBirds and fish disperse the Estuary’s energy andproductivity to ecosystems across the globeEelsAfter maturing in fresh water, adultsswim across the Atlantic to spawn anddie in the Sargasso Sea. The larvae arethought to return on North Atlanticcurrents. Numbers of eels havedeclined hugely in recent years, forreasons which are not fully understood.The previous pages explain how the Estuarygenerates very large amounts of biomass (thesheer weight of living things), most of it fromthe intertidal zone.Because most of the Estuary’s predators arehighly mobile fish and birds, they effectivelytransport the energy and material they pick upin the mud to other places. This energy andmaterial is carried in these animals’ bodytissues and guts, and transmitted via theirparticipation in other ecosystems where theyfeed, are fed on, and eventually die anddecompose. Millions of fish and birds movingaround is impressive enough, but they keep upthese movements year after year, and thecumulative effect is astronomical. Without theSevern’s effect as a stopover and refuel facility,for example, the Arctic tundra couldn’tsupport so many migratory waders. Withoutits effect as a huge fish nursery, the Celtic Sea(and the Atlantic Ocean beyond) could notsupport so many salmon, sprats or mackerel.This extreme interconnectedness is whatmakes altering the Severn’s intertidal habitat sorisky. Does the Estuary’s energy prize justifysevering these global wildlife links, with theirbenefits to people which are not yet fullyunderstood?Dispersal happens across the UK tooLittle is known of the eel’s migration routesSalmonPrincipal feeding grounds are north ofthe Faeroes; adults are at sea for up tofour years. Most populations are indecline. The sea trout, another migrant,is thought to stay near the UK coast, asdo the allis and twaite shad (the Severnshad are genetically distinct species).Mike LanePREVIOUS PAGEThe Gwent LevelsHabitat for a huge diversityof birds. Many are relianton the Estuary’s mudflatsfor their source of foodThe Severn’s tributariesThe rivers are fine habitatsfor resident and migratoryfish which feed in (andpass through) the EstuaryThe Somerset LevelsThe Levels and the RiverParrett are excellenthabitats for resident andmigratory birds, many ofwhich feed in the EstuaryThe local effectAnimal movements disperse largequantities of energy and materialfrom the Severn Estuary toneighbouring systems in theregion. The key areas to benefitare the rivers Parrett in Somerset,Usk in Wales, the Wye either sideof the border, and the Gwent andSomerset LevelsReasons for salmon declines are complexBirdsWith several dozen species andsub-populations involved, the routesshown here are hugely simplified. Butessentially there are three sorts of birdmigration through the Estuary.The spring passage from Africa,branching west to breeding grounds inIceland and Greenland, or east tonorthern Europe and Russia.The return journey, from late June toOctober, by adults and young.The winter visitors, which don’t gofurther south than the Estuary, andreturn north in spring to breed.Bar-tailed godwits: 300 grams of pure energyLaurie CampbellColin VarndellNEXT PAGE18 The Wildlife Trusts’ Severn Estuary reportThe Wildlife Trusts’ Severn Estuary report 19

The optionsThere are five on the shortlist, with three SETS options needing furtherresearch. Here are their environmental, energetic and cost analysesThese are the choices facing the UKGovernment as it tackles ourclimate change targets. Eachoptions will affect the Estuary’sprotected species and habitats.However, The Wildlife Trusts believe thedecision should be taken on the basis of leastenvironmental damage and best costeffectiveness.In general the proposals create three adverseimpacts, none of them well understood:1. Reduce upstream tidal range. This islikely to depress the productivity of themud-based food webs, affecting everythinghigher up the food chain – including people.Estimates of intertidal habitat loss vary hugely,from 2,800ha (Tidal Fence) to 20,000ha(Cardiff-Weston barrage).2. Change the way sediment moves around.Different erosion and deposition patterns arelikely to greatly alter the quality and extent ofmarine habitats, and of the surrounding coast,but the Estuary’s physical processes remainlargely unstudied.3. Threaten populations of migratory fish.Estimates of what the impacts might be arehampered by a lack of baseline data.Despite these uncertainties the Cardiff-Weston Barrage would, without question,have by far the highest environmental impact.The smaller barrages and two lagoon schemes(in their various forms) would be likely to havean intermediate impact. The SETS options(labelled in green below) would have thelowest impact.The Government’s own environmentalreport expresses low confidence in thepossibility of minimising the impacts of abarrage or lagoon development, and increating compensatory habitat. In fact itdescribes the chance of finding like-for-likehabitat elsewhere as ‘impossible’. Any habitatcreation, it admits, would have to be on an‘unprecedented’ scale.The Wildlife Trusts want to ensure thechosen option will not be something thatsociety regrets in decades to come.Twenty miles from thesea, the Severn Boresweeps upstream. Butfor how much longer?What the acronyms meanSAC = Special Area of Conservation cSAC = candidate Special Area of ConservationSPA = Special Protection Area Ramsar = internationally important wetlandSimonwyndham.co.ukShortlistedShortlisted Shortlisted ShortlistedPREVIOUS PAGEBeachley BarrageSmallest barrage, lowest adverseimpact, but lowest energy potentialtoo. Located above the Wye, so fishpassage to SAC rivers still possible.Wholly within the cSAC, SPA andRamsar, so significant loss of habitat.Shoots BarrageCardiff-Weston BarrageFleming LagoonHabitat loss3500ha Habitat loss same or less thanHabitat loss5000haHighest energy and overall impact, Habitat loss20,000ha The longest structure, all of it in Habitat loss6500ha% within protected area 100% Fleming, but no fish passage to the % within protected area 100%with far more intertidal habitat loss % within protected area >95% cSAC. Impacts to migratory fish and % within protected area 100%Claimed power0.625 GW upper Severn and the Wye SAC. Claimed power1.05 GWthan any other option. Fish passage Claimed power8.64 GW freshwater habitats likely to be less Claimed power1.36 GWConstruction cost£2.3bn Wholly within the cSAC, SPA and Construction costs£3.2bnto all tributary rivers impeded,Construction costs £20.9bn than barrages, but would greatly Construction costs£4bnCO2 savings per year 0.7mt Ramsar, so significant loss of habitat CO2 savings per year 1.2mtleading to likely regional extinction of CO2 savings per year 7.2mt affect CO2 savings per year 1.0mtCost per unit of energy 12.6p/kWh Cost per unit of energy 10.4p/kWhCost per unit of energy 12.9p/kWh Eco-friendly erosion barrage and sediment application of the Spectral Cost per Marine unit of energy Energy Converter. 15.5p/kWhand disturbance during construction.Atlantic salmon and twaite shad.movements around the wall.Shortlisted SETS option SETS option SETS optionBridgwater LagoonExtends across smaller proportion ofEstuary than Fleming Lagoon, solikely to have less impact on erosionand siltation. Impedes fish migrationto Rivers Parrett, Cary and Brue.Relatively low carbon saving.Habitat loss5000ha% within protected area 100%Claimed power1.36 GWConstruction costs£3.8bnCO2 savings per year 1.1mtCost per unit of energy 13p/kWhBy kind permission of Parsons Brinckerhoff By kind permission of Parsons BrinckerhoffTidal ReefLeast technically developed option,so estimate for intertidal loss likely tobe less accurate. Turbines likely toturn more slowly than in barragesand lagoons, posing a lower risk tofish. Large footprint is outside cSAC.Habitat loss8600ha% within protected area 0%Claimed power5 GWConstruction costs £18.7-19.8bnCO2 savings per year 5.6mtCost per unit of energy 20.3p/kWhBy kind permission of Parsons Brinckerhoff An artist’s impression © Evans Engineering, 2008Tidal FenceRelatively low impact over a widearea. Partial barrier and low turbinespeed less harmful to migratory fish.Less impact on siltation/erosion too,due to constant flow. Largeconstruction footprint, outside cSAC.Habitat loss2800ha% within protected area 0%Claimed power1.2 GWConstruction costs £6.5-6.9bnCO2 savings per year 1.4mtCost per unit of energy 22.72p/kWhBy kind permission of Parsons BrinckerhoffBy kind permission of STFCSpectral Marine Energy ConverterA series of pillars supporting acauseway road. Structures in theHabitat lossnot known% within protected area not knownpillars use very high speed turbines Claimed power not knownFigure 5. SMEC Barrage Section is lowered into place between pre-driven sheet pilingcoffer to generate dams ontoelectricity. the pre-prepared Tidal terrace flow level is foundation.ConstructionGaps aroundcostsand underneathnot knowntheSMEC only Barrage partly impeded. Section are then Data grouted. and Sections need CO2 only savings be joined per year at roadway not level, known asmore fully determined in detailed design.Cost per unit of energy not knownlocation not yet available.By kind permission of Parsons BrinckerhoffBy kind permission of Verd ErgNEXT PAGE20 The Wildlife Trusts’ Severn Estuary reportThe Wildlife Trusts’ Severn Estuary report 21

David SlaterWhat kind of a worlddo we want to live in?It is time to understand that we are part of nature, not outside of itStarlings atsunset, secondSevern crossingPREVIOUS PAGEWe are becoming more andmore aware of the impactswhich our everyday liveshave on the environmentin which we find ourselves.We must now take the next step: to realise thatyes, we are part of our ecosystem – not someseparate entity existing apart from the fish, thebirds, the worms and the mud.This understanding changes our idea of theworld we want to live in. Of course we needenergy – and the Severn Estuary presents anexciting and all too tempting option to providea large slice of the UK’s renewables. But wecannot view our energy needs in isolationfrom our environment. To do so could easilybe self-defeating. Why should this be so?As climate change takes hold, the changesin our environment are becoming ever moreapparent. We must therefore ensure that ourenvironment is one that can adapt to theseglobal changes, not decline under growingpressure. For this to happen we need to createboth a Living Landscape and Living Seas – ourvision for the future.We often think of renewable energy asbeing environmentally-friendly. But if thewrong decisions are taken in the Severn – thewrong technology selected, in the wrongplaces – then renewable energy has thepotential to destroy all that we rely upon.That destruction would not only affect theEstuary’s internationally recognised wildlifeand habitats. The shape and structure of theEstuary itself would change, and this couldhave serious consequences for our flooddefences. Then there are the ‘silent’ impacts –It is self-defeating to view ourenergy needs in isolation fromour natural environmentthose which will take time to become evident,some of which we simply cannot foresee.The Wildlife Trusts believe that none of theshortlisted options is cost effective, and all fivecould destroy one of the most prized naturalresources in the country. Whilst we recognisethat the SETS options are still in their infancywe believe they demonstrate the most promise.We have a moral and ethical obligation toensure that the least environmentallydamaging,most cost-effective option isselected. So we need to fully investigate all theoptions, to make sure that the technology isright for the job. Most of all we need to ensurethat decisions we take now, in the face ofclimate change, are not ones that we will liveto regret in years in come.The Wildlife Trusts believethat a sustainable future canonly come from workingwith natural processes, notagainst themAndrew KerrNEXT PAGE22 The Wildlife Trusts’ Severn Estuary reportThe Wildlife Trusts’ Severn Estuary report 23

What you can doCLICK HEREto see theSevern Estuary’swildlifehighlightsEmail or write to your MPExpress your concerns about taking the right decision, for the Estuary and peoplealike. You can find out who your local MP is by visiting theyworkforyou.com12Join our campaignKeep an eye on wildlifetrusts.org for further news and developments, and specificdetails of how to help.3VolunteerIf you would like to give your time to help The Wildlife Trusts’ campaign, pleasecontact your local Wildlife Trust (if you’re in Wales or the South West) or visit ourvolunteering pages on wildlifetrusts.org.4Enjoy the Estuary!Visit your local Wildlife Trust’s reserves in the area, or simply get out and about inthe natural wonder that is the Severn EstuaryEditor Rupert Paul. Layout editor Phil Long. Researcher Liz Walker. Project co-ordinator Dr Lissa Goodwin. Printed by Fisherprint, Peterborough.Cover picture skyscan.co.uk. Back page picture David Woodfall. Copyright The Wildlife Trusts 2010.References: P5: Location of options based on Department for Energy and Climate Change (DECC) data. P16/17: Ecosystem flow information by DrRick Park, Gwent Wildlife Trust. Severn facts: British Geological Survey 1996; Dargie, 2000. P18/19: bird migration routes supplied by Mark Ward,RSPB. Salmon migration route: CEFAS, also Tony Andrews, Atlantic Salmon Trust, www.nasco.int/sas/salseamerge.htm. P20/21: Shortlisted andSETS option performance data from DECC report.