IMPACTS AND RISKS TO FISH AND FISH HABITATS OF PROPOSED NEXT GENERATION HYDRO DAMS IN YUKON

Transcription

1 IMPACTS AND RISKS TO FISH AND FISH HABITATS OF PROPOSED NEXT GENERATION HYDRO DAMS IN YUKON Presentation to the Workshop: Hydro Alternatives for the Yukon September 30, 2015 AL von FINSTER Independent Consultant DON REID Wildlife Conservation Society Canada

2 What is this presentation? It covers the following issues: Ø Impacts of hydro dams and reservoirs on fish Ø Reservoir production of mercury and greenhouse gases Ø The timing of environmental assessment in a mega-project It is a summary of knowledge from published studies and reports, coupled with experience and insights of a Yukon fish habitat specialist.al von Finster

3 NEXT GENERATION HYDRO PROJECT HAS SELECTED TEN POTENTIAL SITES Map compiled by WCS Canada ( Lila Tauzer ) and derived from Midgard Consultants Inc report for Next GeneraQon Hydro

4 The Next Genera,on Hydro Project is a major environmental concern Hydroelectric Dams & Reservoirs built across major rivers have bad history of heavy environmental impacts many of which cannot be mi,gated Why repeat bad history?

5 What are the likely impacts and risks to fish and fish habitat? Impacts and risks of Dam New reservoir upstream New river downstream

6 Preliminary list of fish species in upper Yukon and Liard drainages Upper Yukon Upper Liard Common Name Latin Name River River Chinook Salmon Oncorhynchus tshawytcha Y N Chum Salmon Oncorhynchus keta Y N Lake Trout Salvelinus namaycush Y Y Northern Dolly Varden Salvelinus malma malma?? Bull Trout Salvelinus confluentus? Y Arctic Grayling Thymallus arcticus Y Y Lake Whitefish Coregonus clupeaformis Y Y Broad Whitefish Coregonus nasus Y N Round Whitefish Prosopium cylindraceum Y Y Mountain Whitefish Prosopium williamsoni N Y Pygmy Whitefish Prosopium coulteri Y? Least Cisco Coregonus sardinella Y N Inconnu Stenodus leucichthys Y N Northern Pike Esox lucius Y Y Burbot Lota lota Y Y Longnose Sucker Catostomus catostomus Y Y White Sucker Catostomus commersoni N? Slimy Sculpin Cottus cognatus Y Y Lake Chub Couesius plumbeus Y Y Arctic Lamprey Lampetra japonica Y N

7 Dams block migra,ons Block upstream migra1ons PopulaQon lost Ø Anadromous species (Chinook) High Risk Ø Freshwater species - High Risk but unquanqfied Ø Species at risk -? Risk Increase mortality in downstream migra1on PopulaQon depleted Ø Anadromous species (Chinook) High Risk Ø Freshwater spp. - High Risk but unquanqfied Ø Species at risk -? Risk Whitehorse Rapids Dam Photo: Don Reid

8 Dams block migra,ons Assist upstream migraqon (fishway, fish ladder, fish li], arqficial propagaqon) Success? Ø Chinook Salmon moderate Ø Other anadromous low Ø Freshwater low to poor Mi,ga,on? Assist downstream migraqon (bypass channels; collect and transport) Success? Ø All species - moderate Whitehorse Dam fishway Photo: Don Reid

9 Reservoirs destroy river habitats Habitats lost Ø Chinook Salmon Ø Chum Salmon Ø River freshwater species (ArcQc Grayling, Longnose Sucker, Dolly Varden ) River-resident species decline / lost Big Salmon River Photo: Al von Finster Chinook Spawning Redds

10 Reservoirs destroy lake habitats Why? - Fluctua,ng water levels & sediment deposi,on Lose lake shallow-water habitats Ø Young of numerous species Lose lake spawning habitats Ø Lake Trout, Lake Whitefish Lose lake winter habitats Ø Lake Trout, Lake Whitefish, Burbot Lake Abraham, North Saskatchewan River Photo: Al von Finster

11 Reservoirs destroy habitats Mi,ga,on? No efficient and costeffecqve measures to miqgate these impacts High cost and / or relaqvely ineffecqve measures: ArQficial propagaqon FerQlizaQon Dredging Photos: Don Reid

12 Dams change rivers downstream of flow changed Ø ReducQon in spring flood BASE LOAD vs PEAK LOAD Sediment load reduced Ø Reduced nutrients Temperature changed Ø Too warm / too cold in summer Aishihik River Photo: Al von Finster Nisutlin River valley Photo: Don Reid

13 Dams change rivers downstream Mi,ga,on? Paeerns of flow Ø No means of avoiding changes, including during base load Ø AVOID PEAK LOADING!! Sediment load Ø Reservoir flushing Ø Side effects bad Temperature Ø Release water from different depths JULY SEPTEMBER Photos: Don Reid

14 Reservoirs create mercury and greenhouse gas pollu,on Mercury accumulates up food web from flooded soils and vegetaqon toxic levels for humans Greenhouse gases released from decomposiqon of flooded vegetaqon Mi,ga,on? Ø Reduce area of flooded vegetaqon & wetlands Ø Remove trees Ø Only partly successful Macmillan River just upstream of Pelly R. area to be flooded Photo: Jamie Kenyon

15 WITH A LARGE IN-RIVER DAM WE WOULD FACE : Ø NUMEROUS DEFINITE NEGATIVE IMPACTS Ø NUMEROUS RISKS OF IMPACTS AS YET UNCERTAIN IN STRENGTH Ø INABILITY TO MITIGATE MANY IMPACTS LARGE HYDRO MAY BE RENEWABLE ENERGY, BUT IT IS NOT GREEN ENERGY

16 Environmental Assessment should be part of decisions about energy op,ons, not an aner-thought. Current Next GeneraQon Hydro process: YTG decides to look for a dam site ( > 10 MW ) Consultants evaluate sites: geophysical hydrological socio-economic environmental ParQcular site chosen Beeer Approach: Inter-governmental & mulq-sector evaluaqon of alternaqve energy supplies: aboriginal treaty rights & Qtle geophysical / hydrological socio-economic environmental Choose a porlolio of energy sources that have social licence, are low carbon footprint, have low environmental impact, and are renewable Environmental Impact Assessment (YESAB) done PrioriQze set of opqons Environmental Impact Assessment (YESAB) done

17 THANKS and NOTES Thanks to YCS for opportunity to participate Funding from The W. Garfield Weston Foundation WCS Canada will publish and circulate a REPORT on this topic in late October Fill in sheet to receive a copy