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 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 NEXT GENERATION HYDRO PROJECT HAS SELECTED TEN POTENTIAL SITES
Map compiled by WCS Canada ( Lila Tauzer ) and derived from Midgard Consultants Inc. 2015 report for Next Genera on Hydro 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 ? What are the likely impacts and risks to fish and fish habitat ?
Impacts and risks of • Dam • New reservoir upstream • New river downstream 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 Dams block migra ons Block upstream migra ons • Popula on lost Ø Anadromous species (Chinook) – High Risk Ø Freshwater species - High Risk but unquan fied Ø Species at risk - ? Risk
Increase mortality in downstream migra on Whitehorse Rapids Dam • Popula on depleted Photo: Don Reid Ø Anadromous species (Chinook) – High Risk Ø Freshwater spp. - High Risk but unquan fied Ø Species at risk - ? Risk Dams block migra ons Mi ga on ? Assist upstream migra on (fishway, fish ladder, fish li , ar ficial propaga on) • Success ? Ø Chinook Salmon – moderate Ø Other anadromous – low Ø Freshwater – low to poor
Assist downstream migra on (bypass channels; collect and transport) Whitehorse Dam fishway • Success ? Photo: Don Reid Ø All species - moderate Reservoirs destroy river habitats
Habitats lost Ø Chinook Salmon Ø Chum Salmon Ø River freshwater species (Arc c Grayling, Longnose Sucker, Dolly Varden )
River-resident species
decline / lost Big Salmon River Photo: Al von Finster Chinook Spawning Redds 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, Lake Abraham, North Burbot Saskatchewan River Photo: Al von Finster Reservoirs destroy habitats Mi ga on ?
No efficient and cost- effec ve measures to mi gate these impacts
High cost and / or rela vely ineffec ve measures: • Ar ficial propaga on • Fer liza on • Dredging
Photos: Don Reid Dams change rivers downstream
Pa ern of flow changed Ø Reduc on in spring flood
BASE LOAD vs PEAK LOAD
Nisutlin River valley – Sediment load reduced Photo: Don Reid
Ø Reduced nutrients Aishihik River Photo: Al von Finster
Temperature changed Ø Too warm / too cold in summer Dams change rivers downstream Mi ga on ?
Pa erns of flow JULY Ø No means of avoiding changes, including during base load Ø AVOID PEAK LOADING !! Sediment load Ø Reservoir flushing Ø Side effects bad SEPTEMBER Temperature Ø Release water from different depths
Photos: Don Reid Reservoirs create mercury and greenhouse gas pollu on
Mercury accumulates up food web from flooded soils and vegeta on – toxic levels for humans
Greenhouse gases released from decomposi on of flooded vegeta on
Mi ga on ? Ø Reduce area of flooded vegeta on & wetlands Macmillan River just upstream of Pelly R. – area to be flooded Ø Remove trees Photo: Jamie Kenyon Ø Only partly successful
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 Environmental Assessment should be part of decisions about energy op ons, not an a er-thought. Be er Approach: Current Next Genera on Inter-governmental & mul -sector Hydro process: evalua on of alterna ve energy YTG decides to look for a supplies: • dam site ( > 10 MW ) aboriginal treaty rights & tle • geophysical / hydrological • socio-economic Consultants evaluate sites: • environmental • geophysical • hydrological Choose a por olio of energy • socio-economic sources that have social licence, • environmental are low carbon footprint, have low environmental impact, and are renewable Par cular site chosen
Priori ze set of op ons Environmental Impact Assessment (YESAB) done Environmental Impact Assessment (YESAB) done 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