Zosel Dam is a dam in the U.S. state of Washington that blocks the

Okanogan River The Okanogan River (known as the Okanagan River in Canada) is a tributary of the Columbia River, approximately 115 mi (185 km) long, in southern British Columbia and north central Washington. It drains a scenic plateau region called t ...

south of Osoyoos Lake to control upstream water levels. The dam was built as part of the larger Osoyoos Lake International Water Control Structure, a joint venture of the Washington State Department of Ecology and the

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

Ministry of the Environment. The dam was designed by the Canadian firm Acres International Limited and built by the American firm Rognlins Inc. Zosel Dam is named for the Zosel Lumber Company which constructed the original dam on the site. Because it impounds a river that crosses the

Canada–United States border The international border between Canada and the United States is the longest in the world by total length. The boundary (including boundaries in the Great Lakes, Atlantic, and Pacific coasts) is long. The land border has two sections: Canada' ...

, Zosel Dam is subject to international water-sharing agreements governed by the

International Joint Commission The International Joint Commission () is a bi-national organization established by the governments of the United States and Canada under the Boundary Waters Treaty of 1909. Its responsibilities were expanded with the signing of the Great L ...

History

The first dam on Lake Osoyoos was built in 1927 by the Zosel Lumber Company using rock-filled timber crib and pilings. The structure impounded a

mill pond A mill pond (or millpond) is a body of water used as a reservoir for a water-powered mill. Description Mill ponds were often created through the construction of a mill dam or weir (and mill stream) across a waterway. In many places, the co ...

where logs were stored before being processed at the Zosel

sawmill A sawmill (saw mill, saw-mill) or lumber mill is a facility where logging, logs are cut into lumber. Modern sawmills use a motorized saw to cut logs lengthwise to make long pieces, and crosswise to length depending on standard or custom sizes ...

. The sawmill stopped operating in the 1960s. In 1946, the

established the International Osoyoos Lake Board of Control to govern the operations of Zosel Dam. This decision was prompted by repeated flooding of the lakeshore. As the 1927 structure aged it suffered failures in 1974 and 1975. This led the

to request a report from the

U.S. Army Corps of Engineers The United States Army Corps of Engineers (USACE) is the military engineering branch of the United States Army. A direct reporting unit (DRU), it has three primary mission areas: Engineer Regiment, military construction, and civil wor ...

in 1978. The requested report "expresse grave concern about the dam's structural integrity", so the Joint Commission asked the Army Corps to plan a replacement structure. The plan was delivered in 1979 and called for a new dam to be constructed about upstream. Construction of the new dam did not begin for several years. An agreement on cost sharing between

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

and

was not reached until 1985, delayed by "fiscal problems" on both sides of the border. Once the agreement was reached, an engineering firm was hired and a final site was selected, closer to the original dam location, . Construction began in 1986 and was completed by 1987, with the completed structure officially commissioned in 1988.

References

* Buildings and structures in Okanogan County, Washington Dams completed in 1987 Dams in Washington (state) {{US-dam-stub