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Deadline nears to comment on dam operations

| December 20, 2005 11:00 PM

The deadline to comment on the proposed draft environmental impact statement for the Var-Q flood control operations is Jan. 3, 2006.

The DEIS is the long-awaited response by the U.S. Army Corps of Engineers and the Bureau of Reclamation, who managed Hungry Horse Dam, to 2000 biological opinions by the National Marine Fisheries Service and the U.S. Fish and Wildlife Service to save the endangered salmon in the Columbia River and the endangered white sturgeon in the Idaho section of the Kootenai River.

The DEIS includes four alternatives and a number of benchmarks. Two of the alternatives include spilling 10,000 to 11,000 cubic-feet per second from the Libby Dam in addition to full powerhouse capacity releases to help boost downstream flows for the endangered white sturgeon. The U.S. Fish and Wildlife Service has been trying to get flows up to about 41,000 cfs since the 2000 biological opinion to save the sturgeon was released.

The preferred alternative of the U.S. Army Corps of Engineers is to continue operations as they have been since 2003 when Var-Q was first introduced. Var-Q mean variable discharges. Under the existing Var-Q, flows would not exceed powerhouse capacity, which depending on the level of the reservoir, is between 25,000 and 26,000 cfs.

This alternative would also meet the needs of threatened bulltrout and continue the late summer drawdown of the top 20 feet of Lake Koocanusa for endangered salmon downstream in the Columbia River.

The document lists the following "unavoidable adverse impacts":

l "Possible flooding under any of the alternatives since Libby Dam cannot prevent flooding under all circumstances."

l Increased likelihood of forced spill because the operating system calls for the reservoir to not be drawdown so low during the winter months.

There are other impacts associated with the various alternatives involving higher flows such as reduced recreational opportunities for swimming and shore fishing on the river downstream of the Libby Dam.

The releases for sturgeon occurring in

late May and June, depending on water temperature, would be tiered to mimic historic runoff of the Kootenai River before Libby Dam.

Afterward flows for downstream salmon have ranged from 16,000 to 19,000 cfs so that the Corps could vacate the top 20 feet of the reservoir as called for in the salmon bi-op by the end of August.

The State of Montana has been trying to extend the releases through the end of September to lower the river flows below the dam to protect habit for aquatic insects and fish, as well as make the river more approachable from shore by recreationists.

That scenario is include in the Mainstem Amendments proposed by the Northwest Power and Conservation Council, which includes two representatives from Montana, Idaho, Washington and Idaho.

Copies of the DEIS are available for public review at many libraries in the Upper Columbia River System or online at

Comments should be mailed directly to Evan Lewis, U.S. Army Corps of Engineers, P.O. Box 3755, Seattle, Wash. 98124-3755 or faxed to him at (206) 764-4470 or e-mailed to no later than Jan. 3, 2006.