OWYHEE DAM HISTORIC DISTRICT
About 20 miles southwest of Nyssa on the Owyhee River
National Register 9/23/2010
The Owyhee Dam Historic District includes Owyhee Dam and 17 associated buildings and features dating from the period of the dam’s construction and its operation since that time. The dam, completed in 1932, impounds Lake Owyhee, which is the storage reservoir serving more than 115,000 acres of land in Oregon and Idaho that are part of the Bureau of Reclamation’s Owyhee Project. Owyhee Dam is a concrete thick-arch dam that was, for a brief time, the highest dam in the world. More importantly, the dam was used as a proving ground for new high-dam technology and engineering practices that became standard practice after this date. Concrete cooling processes that were key to construction of Hoover Dam were first tested at Owyhee Dam. An associated feature is the dam construction office, built in 1927 and now used as a visitor’s center. Also included in the historic district are three residences and outbuildings, built between 1927 and 1929, that continue to house irrigation district personnel who operate the dam. In the 1930’s, immediately after completion of the dam, Reclamation personnel living at the dam developed a park at the site, and remaining park features dating from the 1930’s are part of the historic district.