Rock Island Dam is a hydroelectric

Hydroelectricity

Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy...

 dam

Dam

A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

 on the Columbia River

Columbia River

The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

 in the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Washington. Chelan County Public Utility District

Chelan County Public Utility District

The Chelan County Public Utility District, or Chelan County PUD, provides electric, water, and wastewater public utility services in Chelan County, in north-central Washington, USA....

's Rock Island Dam and Hydro Project was the first dam to span the Columbia, having been built from 1929 to 1933. It is located near the geographical center of Washington, about 12 miles (19 km) downstream from the city of Wenatchee

Wenatchee, Washington

Wenatchee is located in North Central Washington and is the largest city and county seat of Chelan County, Washington, United States. The population within the city limits in 2010 was 31,925...

. By river, the dam is 235 miles (378 km) below the Canadian border and 453 miles (729 km) above the mouth of the river at Astoria, Oregon

Astoria, Oregon

Astoria is the county seat of Clatsop County, Oregon, United States. Situated near the mouth of the Columbia River, the city was named after the American investor John Jacob Astor. His American Fur Company founded Fort Astoria at the site in 1811...

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