Spray plant – outage update

Aug 11, 2011

On May 23, Unit 2 of TransAlta’s Spray hydro plant was in the midst of scheduled major maintenance when Spray Unit 1 experienced a forced outage, effectively stopping water flow from the Spray system into the Bow River at Canmore. On June 2 a moderate controlled spill began at Goat Pond into Goat Creek to help alleviate rising water levels in the Spray Lakes Reservoir.

Despite this preventative release, inflows this year (from rainfall, snowpack and glacial melt) have been very high, and in mid-July the Spray Reservoir reached capacity, spilling over the spillway channel next to Canyon Dam. As a result, there has been higher-than-normal water volume and turbidity downstream.
Today, while levels in the system still fluctuate with glacial melt and rainfall, the peak flows have now passed and levels are steadily declining.

What we’re doing – TransAlta is working closely with regulators, fishing guides and others impacted downstream to keep them up to date on the situation. Although we continue to work around the clock on both units, it will take until early September to get the Spray plant functioning.

While TransAlta is licenced for use of the spillway and is obligated to protect the dams in the interest of public safety, we are committed to mitigating the impacts of this situation. Our efforts to date include: organizing public safety messaging via radio, posting newspaper ads and signage in the area; conducting regular turbidity and flow monitoring; engaging an independent environmental monitor to continually assess impacts; and helping Parks Canada temporarily close bridges and the Goat Creek Trail for public safety.

Taking action to support fish – TransAlta is funding a project to restore and create new fish habitat on the middle Spray River. This proactive mitigation project − a collaboration with Parks Canada, Fisheries and Oceans Canada, Alberta Parks, Alberta Environment and Trout Unlimited − is underway and involves using the current high water flows to create habitat in the form of pools and overhead cover for fish through the placement of large woody debris (tree piles) at several locations within the Spray River system.

Going forward – TransAlta is fully engaged in returning the plants to service and our focus continues to be on public and dam safety. We will also be keeping regulators and stakeholders updated as things progress. For questions, contact 1-877-547-3365, ext. 1.