Koocanusa drawdown request rejected
July 25, 2005
A stalemated biological argument was broken Thursday when federal officials decided to follow prescriptions in National Oceanic & Atmospheric Administration (NOAA) Northwest Region Hydropower Division Fisheries' 2004 Federal Columbia River Power System biological opinion rather than slow the drawdown of reservoirs behind Libby and Hungry Horse dams, as the state of Montana has requested.
According to a story in the Columbia River Bulletin, Fish & Wildlife News, the drawdown was requested to avoid jeopardy to salmon and steelhead in the Columbia River basin which are listed under the Endangered Species Act.
The Biological Opinion calls for Libby and Hungry Horse reservoirs to be refilled by June 30, then drawn down by 20 feet during July and August to elevations of 2,439 feet and 3,540 feet, respectively. The released water is intended to augment flows in the lower Columbia where, primarily, sub-yearling fall chinook from the Snake River, the Columbia's Hanford Reach and elsewhere are migrating toward the ocean.
Conservation groups have called for a drawdown with lesser, "flat" flows that are prolonged through September to better protect the aquatic environment in the reservoirs and Kootenai and South Fork of the Flathead rivers.
Montana officials have stressed that maintaining more stable flows through the most biologically productive season has certain benefits for resident fish in northwest Montana and north Idaho while flow augmentation has no proven or provable worth for salmon in the lower Columbia basin.
The Montana plan called for a stable flow that would draw the reservoirs down by 20 feet over the three-month period. U.S. Army Corps of Engineers officials estimated that would create a flow of about 11,000 to 12,000 cubic feet per second below Libby Dam, which is near the Kootenai River's maximum productive level.
As of Wednesday, July 20, Libby's Lake Koocanusa reservoir, was three feet below full and the Corps was passing 24 kcfs, the powerhouse capacity. Flows into the Kootenai River were cut to 19.2 kcfs Thursday night and the plan was to cut flows to 14 kcfs at the end of next week.
For this summer, NOAA will implement the biological opinion regarding the drawdown rates of Lake Koocanusa and Hungry Horse reservoirs as written.
Related Links:
The Columbia River Bulletin Fish & Wildlife News, Friday, July 22, 2005
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