Hells Canyon Dam

Hells Canyon Dam

Company type	Private
Industry	Hydroelectric power
Founded	1967
Headquarters	Boise , United States
Area served	Snake River, Idaho and Oregon border
Key people	Idaho Power Company (owner/operator)
Products	Hydroelectric power
Parent	Idaho Power Company

Hells Canyon Dam is a concrete gravity structure situated on the Snake River at river mile 247 within Hells Canyon, positioned along the border between Idaho and Oregon. It forms the Hells Canyon Reservoir, which has a spillway elevation of above mean sea level.

As the final and third hydroelectric installation in the Hells Canyon Project, this dam complements Brownlee Dam (completed in 1959) and Oxbow Dam (completed in 1961). All three facilities are developed and managed by Idaho Power Company. This network represents the largest hydroelectric system under private ownership in the United States, according to data from the US Energy Information Administration. The construction contract was awarded to Morrison-Knudsen, based in Boise, Idaho.

The powerhouse at Hells Canyon Dam contains three generating units with a total installed capacity of . Two units were commissioned in 1967, followed by the addition of a third unit in 1968.

The absence of fish passage infrastructure prevents anadromous salmon from migrating upstream beyond Hells Canyon Dam toward Shoshone Falls, which serves as a natural barrier restricting access to the upper Snake River basin.

High dam proposal

In the 1940s, plans were initially made for a single tall concrete gravity dam at Hells Canyon, designed to be high and equipped with two gate-controlled tunnel spillways. Instead of this single structure, three dams—Hells Canyon, Brownlee, and Oxbow—were constructed, replacing the original concept of one large dam.

The envisioned reservoir was projected to store over and extend upstream for . The power generation facility was planned to include ten units with a combined output of 850 MW. Additionally, fish hatcheries were incorporated into the design to support salmon populations. The estimated cost for this publicly funded project was $342 million.

This high dam proposal became a controversial political matter in Western states. Oregon senators Wayne Morse and Richard L. Neuberger championed the public dam initiative but encountered resistance. Some Western senators allied with Southern Democrats to weaken the 1957 Civil Rights Act in return for support of the public dam project. Nevertheless, Idaho Senator Frank Church, who strongly supported both the dam and the Act, denied any exchange of favors.

In the end, the plan for the high dam was discontinued.

See also

• List of power stations in the United States
• List of dams in the Columbia River watershed

External links

• Hells Canyon Dam, Northwest Power and Conservation Council
• Hells Canyon Complex, Idaho Power