Lake Koocanusa is a 90-mile-long reservoir that lies behind 422-foot-tall Libby Dam, located 16 miles upstream from the town of Libby. Completed in 1972 as a joint project between the United States and Canada, Libby Dam was an effort to provide flood protection and to generate hydroelectric power. The Kootenai River fluctuated wildly in the spring causing flooding in Montana, Idaho, and British Columbia. Lake Koocanusa received its name in a contest to name the Libby Dam reservoir. Alice Beers, from Rexford, Montana, combined the first three letters from KOOtenai River, the first three letters of CANada, and USA.