Water Level At Dworshak Dropping For Planned Repairs

The water level in Dworshak Reservoir has started dropping as the U.S. Army Corps of Engineers increases flows to prepare for dam repairs.

The flow Tuesday started rising from 9,400 cubic feet per second to 22,400 cfs, said Roy Brown, powerhouse operator. The reservoir level was about six feet below full pool Friday, he said.

The reservoir will fall two feet per day until it is about 70 feet below full by Aug. 15.

The Army Corps wants the level down to allow contractors to inject cement grout into cracks in the bedrock beneath the dam. Lower water levels reduce the pressure.

A 1995 attempt to grout the cracks failed when a December flood caused the reservoir to jump dramatically, forcing work to stop.