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'Substantial gaps' in research on Whitehorse dam impacts on fish, DFO says

There are gaps in the research into how the Whitehorse dam is affecting not just salmon but also other fish species, says the Department of Fisheries and Oceans (DFO) in a letter submitted to assessors looking at Yukon Energy's proposal to relicense dam for another 25 years. 

Federal department's input part of assessment of Yukon Energy's proposal to renew dam's licence for 25 years

The headstock of the Whitehorse dam in front of Schwatka Lake. Water is rushing through the spillway. The scene is surrounded by boreal forest.
Yukon Energy's hydroelectric dam in Whitehorse. The Department of Fisheries and Oceans says the full extent of the dam's impacts on fish species are 'unknown.' (Paul Tukker/CBC)

There are "substantial gaps" in research into how the Whitehorse dam is affecting not just salmon but also other fish species, according to a new letter from the Department of Fisheries and Oceans (DFO) regarding Yukon Energy's proposal to relicense the facility for another 25 years. 

The letter, which the federal department submitted to the Yukon Environmental and Socio-economic Assessment Board (YESAB), states those gaps in research impede a scrupulous review of the project. It says the full impact of the hydroelectric dam is "unknown."

"Although the proponent did provide fish and habitat information, there are gaps in baseline aquatic information provided," states DFO, a decision body in the project assessment.

"Without this baseline information, DFO is unable to understand the full effects of the continued operation of [the dam] on fish and fish habitat."

Yukon Energy's current operating licence for the dam expires next May.

This is the first time the facility, built in 1958, is undergoing a review by the assessment board. Crucial for many people is how to protect chinook salmon and other fish like grayling and Northern pike.

The letter from DFO states the cumulative impacts of the dam in relation to the precipitous decline of Yukon River chinook salmon need to be considered by the board, along with whether a 25-year licence renewal would be appropriate.

Some citizens of the Carcross/Tagish First Nation have written to the assessment board, saying that that time frame is too long, whereas a 10-year licence period, for instance, would ensure more studies into the dam's impacts.

The information DFO is seeking includes data on fish that are killed when they pass through the dam, stranding risks downstream and upstream and whether the Whitehorse fish ladder is effective. The department also wants the Lewes control structure, which is ancillary to the dam and regulates water flow downstream to Whitehorse and beyond, to be assessed to determine just how well fish can pass through it.

A dark red fish in grey-green water seen through a window surrounded by wood walls.
A lone chinook salmon swims by an underwater viewing window at the Whitehorse fish ladder in August 2022. (Jackie Hong/CBC)

In an email to CBC News, a spokesperson for Yukon Energy said the company is confident in the research it's collected so far, adding that it thought the information DFO was looking for was expected at a later date.

"Yukon Energy is clarifying with DFO what information would be helpful to them, and when," wrote Lisa Wiklund. 

"We know that protecting fish and fish habitat is important to DFO. They helped design the current fish ladder at the dam ... When the fourth turbine was added in 1984, it was DFO that required the Whitehorse fish hatchery be built and operated."

Prompted by the Kwanlin Dün First Nation, the Ta'an Kwäch'än Council and the Carcross/Tagish First Nation, the company has bankrolled a study into how the dam could be killing juvenile chinook salmon at potentially high rates. Yukon Energy has also said it plans to improve the fish ladder and figure out a way to steer fish away from the turbines.

'Yukon Energy really has to catch up'

Al von Finster, a local fish biologist, said Yukon Energy has long focused on salmon over other species. DFO's recognition of this is a positive, he said, because a healthy ecosystem is at stake. 

Yukon Energy "hasn't had to deal with all the other species," von Finster said, noting the Fisheries Act has been amended several times in more than a decade.

"Now, DFO looks much more broadly at fish than they did in the past. In the past, they looked at it more or less that a fish had to support a fishery to be covered by the act.

"Right now, [Yukon Energy] is being asked to provide all the species, all the life stages and document" how the dam could be affecting them.

"Yukon Energy really has to catch up."

The project will most likely need approval by DFO under the act, but that's a separate process.

The dam's construction predates certain provisions and was not subject to the legislation.

Sarahlily Stein, with the Yukon Conservation Society, said proposed protections for fish are vague, at best. And the fish hatchery shouldn't be seen as a mitigation, she said. Stein is pleased that DFO is taking a similar tack. 

"What we're saying is that [Yukon Energy] have to invest in more infrastructure to actually prevent killing the salmon instead of just killing them and adding more salmon in like a math equation," they said.  

"It just doesn't really balance."

ABOUT THE AUTHOR

Julien Greene is a reporter for CBC Yukon. He can be reached at julien.greene@cbc.ca