Columbia River Treaty - Treaty Provisions

Treaty Provisions

Under the terms of the agreement, Canada was required to provide 19.12 km³ (15.5 million acre-feet (Maf)) of usable reservoir storage behind three large dams. This was accomplished with 1.73 km³ (1.4 Maf) provided by Duncan Dam (1967), 8.76 km³ (7.1 Maf) provided by Arrow Dam (1968), and 8.63 km³ (7.0 Maf) provided by Mica Dam (1973). The latter dam, however, was built higher than required by the Treaty, and provides a total of 14.80 km³ (12 Maf) including 6.17 km³ (5.0) Maf of Non Treaty Storage space. Unless otherwise agreed, the three Canadian Treaty projects are required to operate for flood protection and increased power generation at-site and downstream in both Canada and the United States, although the allocation of power storage operations among the three projects is at Canadian discretion.

The Treaty also allowed the U.S. to build the Libby Dam on the Kootenai River in Montana which provides a further 6.14 km³ (4.98 Maf) of active storage in the Koocanusa reservoir. Although the name sounds like it might be of aboriginal origins, it is actually a concatenation of the first three letters from Kootenai / Kootenay, Canada and USA, and was the winning entry in a contest to name the reservoir. Water behind the Libby dam floods back 42 miles (68 km) into Canada, while the water released from the dam returns to Canada just upstream of Kootenay Lake. Libby Dam began operation in March 1972 and is operated for power, flood control, and other benefits at-site and downstream in both Canada and the United States, and neither country makes any payment for resulting downstream benefits.

With the exception of the Mica Dam, which was designed and constructed with a powerhouse, the Canadian Treaty projects were initially built for the sole purpose of regulating water flow. In 2002, however, a joint venture between the Columbia Power Corporation and the Columbia Basin Trust constructed the 185 MW Arrow Lakes Hydro project in parallel with the Keenleyside Dam near Castlegar, 35 years after the storage dam was originally completed. The Duncan Dam remains a pure storage project, and has no at-site power generation facilities.

The Canadian and U.S. Entities defined by the Treaty, and appointed by the national governments, manage most of the Treaty required activities. The Canadian Entity is B.C. Hydro and Power Authority, and the U.S. Entity is the Administrator of the Bonneville Power Administration and the Northwestern Division Engineer for the U.S. Army Corps of Engineers. The Treaty also established a Permanent Engineering Board, consisting of equal members from Canada and the U.S., that reports to the governments annually on Treaty results, any deviations from the operating plans, and assists the Entities in resolving any disputes.