Unnaturally high and dirty water levels in Goat Creek and Spray River has Banff National Park authorities concerned about harm being caused to fish and their habitat.
TransAlta has been diverting significant volumes of water into Goat Creek since June 3 following mechanical breakdowns and planned maintenance at the Spray hydroelectric facility.
Making matters worse, the power company now predicts large volumes of water will breach the spillway at Canyon Dam into Spray River by mid-July due to ongoing runoff and problems at the reservoir.
Parks Canada fears turbidity created by sediment being stirred up from the increased force of the flows will affect fish survival and destroy or alter habitat, such as holding areas.
“As a result of these increased flows and duration of flows, our concern is what could or will happen to the fish populations in the Goat, in the Spray and also in the Bow,” said Parks aquatics specialist Charlie Pacas.
“The Spray River is 40 kilometres from Canyon Dam to Bow Falls and the habitat may be changed to some degree as a result of all of this. We think fish populations may be affected.”
Local fishing guides are up in arms, too.
They guide on the section of the Bow River outside the national park, but note there is a dramatic difference between the colour of the Bow above and below the confluence with the Spray River near Bow Falls.
Nick Schlachter, owner of Canmore-based Wapiti Sports and Outfitters, said the increased turbidity in the water is a “big concern”, as guides rely on this time of year for their livelihood.
“It’s been higher and dirtier than usual and that’s a big concern because we do tours and guide,” he said. “It’s pretty hard to take clients out, and there’s lots of people complaining. This has a huge impact; it’s our season, we rely on those summer months.”
A combination of mechanical failure and planned maintenance at the Spray hydroelectric facility has resulted in significantly more water being diverted into Goat Creek.
The Spray hydroelectric plant operates with two units and one was down for scheduled servicing and maintenance when the second failed on May 23.
TransAlta began diverting water into Goat Creek on June 3 and it’s anticipated mechanical problems at the reservoir can’t be fixed until Aug. 1.
Coupled with substantial snow pack and spring run-off, Goat Creek is expected to see flows of up to 250 cubic feet per second compared to its usual 20 to 60 cubic feet per second.
When the water tops the spillway at Canyon Dam sometime next week, it’s expected flows into Spray River will go from 15 to 20 cubic feet per second to an estimated 500 to 1,000 cubic feet per second.
“We are continuing to work around the clock to get the Spray power plant turbines up and running,” said Glen Whelan, TransAlta’s public affairs manager.
Whelan said they are regularly monitoring flows and turbidity levels in the Bow, Spray and Goat, but said turbidity levels have been quite natural in the Bow up to this point.
He said an independent environmental regulator has been hired to collect data to keep regulators up to speed, including the province of Alberta and Parks Canada.
“Our focus at the moment is on public safety and managing the Spray Reservoir,” he said.
“We are also monitoring things to make sure, at end of day, we will be able to remediate and mitigate any impacts.”
Pacas said Parks had an understanding of fish numbers and species in the system before these TransAlta events, but less of an idea about habitat. There will be a need for some post-event monitoring, too.
“We are still trying to work through all this, but this would be something TransAlta should have some responsibility for,” he said.
Whelan said TransAlta is posting warnings along the Spray River, similar to what they have done at Goat Creek, as water levels in the Spray Reservoir continue to rise.
“The spring melt is continuing and flows are unseasonably high, so we’re expecting sometime around mid-July for water to flow through the canyon dam spillway,” he said.
“We’d expect flows to increase substantially in the Spray River and to increase a little bit on the Bow River.”
