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New habitat created for fish in Spray River

A threatened fish population in Banff’s Spray River has been given a fighting chance in the wake of a massive restoration effort of habitat destroyed as a result of a faulty hydroelectric facility.
Helicopters were used to place trees in the Spray River to improve fish habitat.
Helicopters were used to place trees in the Spray River to improve fish habitat.

A threatened fish population in Banff’s Spray River has been given a fighting chance in the wake of a massive restoration effort of habitat destroyed as a result of a faulty hydroelectric facility.

TransAlta has spent up to $500,000 to restore habitat in the mid-section of the Spray River, including dropping 450 to 500 trees by helicopter and rafts into the river to create new pools where fish can thrive.

Crews equipped with electro-fishers then saved about 2,000 fish that would have been stranded in remnant pools and side channels once water stopped breaching a dam and dirty and unnaturally high water levels subsided.

Parks Canada officials, who were initially worried about fish survival and destruction of habitat, say they have not received any reports of dead fish in the Spray, which is home to threatened cutthroat trout.

“The initial assessment is things are looking fairly good,” said Bill Hunt, resource conservation manager for Banff National Park.

“TransAlta has put in a genuine effort with this. They’ve stepped up and done everything reasonably possible to mitigate the impacts at this point.”

Led by Parks Canada, TransAlta and Trout Unlimited worked to put together six teams of electro-fishers to scour most of the river for any signs of stranded fish for three days, Sept. 14-16.

Hunt said about 2,000 fish were put back into the main river, noting about 95 per cent of those were brook trout. There were about 40 bull trout and 10 to 15 cutthroat trout.

He said Golder Associates will monitor the success of the restoration effort, including habitat quality and fish abundance, to compare with data Parks Canada has for about five different sites along a 30-kilometre stretch of river.

“The research will help us come up with an overall plan to see if everything’s good, or whether more habitat work is need, and whether restoration of invertebrates or fish is needed.”

The drama began on May 23, when one of two generators at TransAlta’s hydroelectric plant below Grassi Lakes in Canmore was down for scheduled maintenance and a second failed.

The power-generating giant had no option but to shut off the flow of water and let it build up at Spray Lakes Reservoir, in part controlled by the Canyon Dam.

The diversion of water started at Goat Pond on June 3, sending significant volumes of water into Goat Creek. Making matters worse, water breached the spillway at Canyon Dam into the Spray River around mid-July.

Goat Creek flows into the Spray River, which in turn flows into the Bow River. The diversions, combined with a big spring runoff, led to swollen, dirty waters.

Glen Whelan, TransAlta’s communications director, said the spill-over at Canyon Dam gradually declined, before completely stopping on Sept. 20, while the controlled spill into Goat Creek from Goat Pond ended Sept. 26.

He said Spray unit No. 1 returned to service on Sept. 10, while the second unit is in the reassembly stage and TransAlta plans to have it in service in November.

“The Spray system has returned to normal operation with hydro-electrical generation at the Three Sisters, Spray and Rundle plants,” he said.

Whelan said Golder Associates – an environmental consulting company – was enlisted to do monitoring before, during and after water began breaching Canyon Dam spillway and this work will continue into 2012.

“Post-event monitoring will continue and we will continue to work with all of our colleagues, neighbours and stakeholders,” he said.

At the height of the problem, waters gushed into the Spray River at up to 50 times the normal rate. The water flow in the Spray River is typically 15 to 20 cubic feet per second.

As for the Bow River, there is not as much information on environmental affects, although a lot of woody debris washed out of the Spray and has caused several log jams that may be hazardous to paddlers in spring.

Hunt said when TransAlta shut off the water flow in the Cascade River for maintenance work at its Cascade plant, there were many more fish salvaged than expected.

“They moved over 130 fish out of that system, where the last time they did that it was around 35 fish,” he said.

“It looks like a lot of fish were seeking refuge up the Cascade from the Bow River. We may have gotten lucky that enough fish were able to find micro-sites free of sediment.”

Hunt said TransAlta covered all the costs associated with the restoration work in the Spray River, including Parks Canada’s time, materials and helicopters.

TransAlta said the budget was “less than $500K”.

Meanwhile, Goat Creek trail remains closed.

In conjunction with Parks Canada, Whelan said TransAlta disassembled an older wooden bridge on July 29 that crossed the Spray River, and which is part of the Goat Creek trail.

“With flows now returned to normal, TransAlta is working on a new weathered steel replacement bridge,” he said. “We are finalizing the detail design and will use best efforts to install it this fall.”


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