Fourth Generator Posed For Dworshak

The U.S. Army Corps of Engineers has received a proposal to add a fourth hydroelectric unit to Dworshak Dam.

Dworshak manager Charles Krahenbuhl said a consultant to Utah Power & Light Co. has proposed installing a 40-megawatt generator at the dam near Ahsahka along the Clearwater River’s North Fork. That is half the size of two of the three generators now operating at the dam.

A similar proposal by the corps to build a much bigger generator more than a decade ago prompted protests from steelhead anglers. The larger unit would have caused wild fluctuations in river levels.

Krahenbuhl said the new proposal came from consultant Mark Steinley, who suggested that Utah Power & Light was interested. The small generating unit would be sized to operate at full efficiency with the 1,200 cubic feet of water a second the dam must release as a minimum flow in the North Fork.

“What I’ve heard is they would like to size it for the minimum flow we have in the summer time,” Krahenbuhl said.

That water now is used to turn one of the smaller generators at the dam, but it operates less efficiently than a smaller generator would, he said.

Krahenbuhl said the proposed generator has not gained enough support for a public review.

“We don’t have a lot of detail. It would bring up some interesting questions about who would operate it, maintain it, install it,” he said.

A smaller project likely to spark less conflict is in the works for the waterline that feeds fish hatcheries below Dworshak Dam. The state has asked the Federal Energy Regulatory Commission for permission to build a 2.5 megawatt generating unit on the line that supplies Clearwater and Dworshak hatcheries with water from the reservoir behind the dam.