Until 2002, Libby Dam flow releases were authorized under Standard Flood Control procedures. Under Standard Flood Control, minimal flows were released from the dam between May and July, while relatively high flows were released from January through April in order to evacuate storage capacity to capture the spring runoff. This operating strategy maximized flood control and hydropower generation on both sides of the border. 

In December 2000, the US Fish and Wildlife Service and National Marine Fisheries Service (a division of the US National Oceanic and Atmospheric Administration) each issued a Biological Opinion outlining measures to protect endangered species including sturgeon, bull trout, salmon and steelhead. A Variable Flow Flood Control (VARQ ) release procedure was implemented in 2003 to improve flows for endangered fish species shown to be threatened by Standard Flood Control operations. Variable Flow Flood Control releases result in a more natural hydrograph, with spring/summer peak flows still considerably reduced, although higher than the level that existed under Standard Flood Control releases.

During the Columbia River Treaty Review public consultation session in Creston on May 30, 2012, the Columbia River Treaty Review team became aware of the community’s concerns regarding the erosion of area dykes that protect important farmland and other values. Representatives of the dyking and regional districts expressed concern that implementation of Variable Flow Flood Control at Libby dam has resulted in increased bank erosion along the approximately 46 kilometer portion of the Kootenay River that runs from the Canadian/U.S. border downstream to Kootenay Lake, which in turn has impacted dyking infrastructure located immediately adjacent to the river.

The Columbia River Treaty Review Team has contracted BGC Engineering Inc. to undertake an evaluation of these concerns. BGC Engineering Inc. is analyzing data, including streamflow records, reviewing previous reports on bank erosion and is also contacting the US Army Corps of Engineers to establish whether dykes in Idaho have  been similarly affected by Libby Dam flow releases. A report summarizing the data analysis and providing conclusions as to the impact of Libby Dam operation is expected to be completed and available to the public by mid-November, 2012.

A summary of the report will be posted on the Columbia River Treaty Review website at gov.bc.ca/columbiarivertreaty.