UPDATE: Spray River Mitigation Project
November 1, 2011
A helicopter places trees in the Spray River © Parks Canada / C. Pacas
Over 38 new fish pools have been added to the Spray River thanks to TransAlta and Parks Canada crews who have been working together on a mitigation project to restore and create fish habitat on the Spray River following a TransAlta spill event this past summer. Over 50 km of waterways in the Spray, Goat, and Bow drainages were affected by late season flooding and high sediment levels stemming from maintenance issues at TransAlta facilities near Canmore.
The spilling event resulted in:
- fish habitat loss (especially over-wintering pools)
- threats to fish and invertebrates populations due to high flows and sediment load (full extent to be determined)
- closure of the Goat Creek Trail and removal of several footbridges
- loss of recreational use (hiking and biking) on the Goat Creek Trail
- loss of angling opportunities in the area
In late August and early September, crews positioned over 500 trees in the Spray River to create pool habitat for fish. In addition, after flows began to recede aquatics specialists salvaged over 2000 fish from side channels and placed them back into the main waterway.
This fall and the two agencies will cooperate to assess the impacts of both the flooding and the mitigation efforts. We will work to repair the bridge and our goal is to open the Goat Creek Trail in time for cross-country skiing. In the spring, we will examine the over-wintering impacts on fish and invertebrates and determine future mitigation or restoration work.
Why is this important?
The prolonged, high water levels this summer have rearranged, and possibly washed out, the existing fish habitat in the Spray River. The current mitigation measures are an opportunity to replace what was historically lost from the river prior to the construction of the Canyon Dam in 1950, and to decrease the flooding impacts. The creation of pool features could help bull trout during the fall spawning cycle and overwintering. In addition, this habitat creation could support the reintroduction of native Westslope Cutthroat Trout in the future.
August 15, 2011
Parks Canada crews placing trees in the Spray River © Parks Canada/S. Zyvatkauskas
Parks Canada and TransAlta are working together on a mitigation project to restore and create new fish habitat on the Spray Rivefollowing a recent TransAlta spill event. Over 50 km of habitat in the Spray, Goat, and Bow drainages has been negatively impacted by late season flooding and high sediment levels stemming from maintenance issues at TransAlta facilities near Canmore.
Fish, amphibians and invertebrates and their habitats have been threatened by this high flow event. High water flows have also forced the closure of the Goat Creek trail for safety reasons and compromised bridge structure.
During the August 6/7 weekend, as part of a pilot project, Parks Canada crews positioned over 200 trees at key points along a six-km section of the Spray River near the headwaters below Canyon Dam. A total of 11 habitat structures of different sizes were put in place along the river. These measures will create good pool habitat for fish and help lessen the impact of high water flows.
On Monday, August 8, Parks Canada and TransAlta suspended project activity until water flows decreased in order to obtain the best habitat results possible. Parks Canada and TransAlta will continue to monitor and evaluate flows over the next few days and are assessing the possibility of placing larger trees and creating more habitat sites along the river. Work will resume as conditions permit.
Why is this important?
These trees will help create important pool habitat for aquatic species in the Spray River. © Parks Canada/C. Pacas
The Spray River is a major tributary of the Bow River. Since construction of the Canyon Dam in 1950, the reduced water flows have changed the habitat and how it develops in the river, and also how nutrients are dispersed. Decreased water volume has shrunk the size of the river from the original banks, making it difficult for trees and shrubs to contribute the necessary woody debris that create the variety of habitat required by different aquatic species.
Although the Spray River contains various features which provide food, shelter and travel routes for fish, pool habitats are largely absent from the system. Pools in coldwater streams allow fish to rest and overwinter due to their depth and stillness.
The prolonged, high water levels this summer have rearranged, and possibly washed out, the existing fish habitat in the Spray River. The current mitigation measures are an opportunity to replace what was historically lost from the river and decrease the flooding impacts. The creation of pool features could help bull trout during the fall spawning cycle and overwintering. In addition, this habitat creation could support the reintroduction of native Westslope Cutthroat Trout in the future.
- For more information about water flow, or TransAlta facilities, contact TransAlta at 1-877-547-3365.
- For more information about the habitat restoration project, contact Stephenie Zyvatkauskas at 403-762-1431
- Please report any observations of fish mortality or damage to park infrastructure resulting from flooding to Banff Park Dispatch (24 hrs) 403-762-1470.