PPL Montana will begin lowering the elevation of the Thompson Falls reservoir starting Thursday (10/9) to allow for repairs on the dam.

The drawdown, expected to take about four days, will reduce the lake elevation by 11 feet to 2,385 feet. While the lake is lowered, PPL Montana employees will replace damaged flashboards, wooden planks fixed on top of the dam. These repairs will assist with pending fish passage construction and enable the hydroelectric plant to run more efficiently.

“We will draw down the level of the lake just long enough to do the planned work, which should take less than three weeks to complete,” said David Hoffman, director of External Affairs for PPL Montana.

The drawdown is for the safety of employees working on the Thompson Falls Dam, which provides clean, renewable energy for the region, he said. The Thompson Falls hydroelectric plant on the Clark Fork River has a generating capacity of 94 megawatts, enough electricity to satisfy the average energy needs of 70,000 typical households.

“We try to plan maintenance projects such as this during times of the year when the demand for electricity is lower, and the drawdown has less of an effect on recreational users of the reservoir,” Hoffman said.

PPL Montana provides safe, reliable energy from coal-fired power plants at Colstrip and Billings, as well as 11 hydroelectric plants along West Rosebud Creek and the Missouri, Madison, Clark Fork and Flathead rivers. It has a combined generating capacity of more than 1,200 megawatts and has offices in Billings, Butte and Helena. PPL Montana and its 500 employees are dedicated to Montana and its communities, supporting educational, environmental and economic development programs across the state. PPL EnergyPlus operates a trading floor in Butte that markets and sells power for PPL Montana in wholesale and retail energy markets throughout the western United States. PPL Montana and PPL EnergyPlus are subsidiaries of PPL Corporation (NYSE: PPL).