Kerr Dam to Increase Generating Capacity

PPL Montana plans to increase the generating capacity of PPL Montana’s largest hydroelectric facility.

Kerr Dam on Flathead River southwest of Polson, Mont.

The project involves replacing the runner on Unit 3 at Kerr Dam on the Flathead River southwest of Polson, Mont. The upgrade will increase the maximum output of the unit from 70 to 80 megawatts.

A runner, or waterwheel, looks like a spinning wheel, with fixed blades between two rims. A circle of guides surround the runner, controlling how much water drives the turbine. 

PPL Montana had identified the potential for capacity upgrades at the Kerr hydro plant, so when last year’s inspection showed that the 50-year-old Unit 3 runner required repairs, engineers knew that replacing the runner was an alternative to carefully consider.

Kerr’s new runner, about 15 feet in diameter and stainless steel with a carbon steel crown, is scheduled to be installed in the fourth quarter of next year and is expected to be in service in early 2007.