Engineers working to fix mechanical failure at Hebgen Dam

Engineers continue to work to correct a mechanical failure at PPL Montana’s Hebgen Dam near Ennis that increased water flow in the Madison River on Sunday (8/31).

“PPL Montana’s top priority is keeping the public and our employees safe, and our engineers are working to correct the issue,” said David Hoffman, director of External Affairs for PPL Montana. “We see no risk to the stability of the dam.

“We realize the closure of the Madison River is an inconvenience for boaters and river guides, but it’s the right precaution to take to ensure public safety,” he said. “We’re using the best engineering practices to solve the problem and return Hebgen to normal operations as quickly as possible.”

The normal water flow level for this time of year is about 850 cubic feet per second. At 3,400 cubic feet per second, the current water flow is more typical of the levels in May and June.

“Although the river channel is able to accommodate this level of water, we are taking steps to ensure the safety of the public and downstream properties,” Hoffman said.

An engineering team is looking for a solution to lower the flow of water, including installing a temporary bulkhead near the lower gates.

Hebgen Lake is just north of the Idaho border near Yellowstone Park. Hebgen is used to store water from a 905-square-mile drainage area at the headwaters of the Madison-Missouri river system, home to eight PPL Montana hydroelectric plants.

The company will conduct a thorough investigation to determine the cause of the incident.