Idaho Power has completed its annual flow program that keeps water levels steady below Hells Canyon Dam to support spawning Fall Chinook salmon.
Chinook salmon return from the Pacific Ocean to lay their eggs in the Snake River below Hells Canyon Dam each fall. The eggs need the right flow of water to develop, so Idaho Power controls the water released from Brownlee Reservoir from October through December until fish emerge.
Idaho Power holds the flow coming from Hells Canyon Dam within a narrow range during that time. Now that the flow control program has ended, flows below the dam will range from 8,500 cubic feet per second (cfs) to 20,000 cfs as the company generates electricity in response to customer demand.
The flow program is one part of the company’s commitment to supporting salmon populations in the Snake River. More information is available at idahopower.com/fish.