Now a National Historic District, this facility has been in production on the Clark Fork River at the city of Thompson Falls since 1915. Though there is a storage reservoir behind the two dams, it is considered a run-of-the-river facility.
This concrete arch dam is is 913 feet long and 32 feet high.
Now operated by
Northwestern Energy, the facility celebrated its centennial of electricity production in July of 2015. To mark the auspicious occasion, Northwestern Energy held a centennial anniversary ceremony on Power Island, the location of the hydro facility. To record the event for posterity, The Missoulian was on the scene. Their article is reproduced in part below.
Thompson Falls Dam to mark 100 years of hydro
July 07, 2015 7:00 pm • By Kim Briggeman
John D. Ryan came back from Thompson Falls in the summer of 1915 with a glowing report.
The Anaconda Copper Mining Co.'s new dam on the Clark Fork River was up and running, with two of six units already producing power, said Ryan, the company president and the most powerful man in Montana.
“The main use of the electricity will, of course, be that of supplying the new Milwaukee (railroad) electric system,” said Ryan. “Then we will supply the Coeur d’Alene mines, which we are already doing in part. We are, however, still in the market for our power, since we will have a great deal to spare.”
One hundred years of hydroelectric generation later, the dam’s current owner is ready to celebrate.
NorthWestern Energy, which took over control of this and 10 other dams from PPL Montana last November, is planning a centennial anniversary ceremony from 11 a.m. to 2 p.m. Friday at Power Park, half a mile downstream from the main dam.
“We’re going to have dam tours, serve hot dogs and have other information available,” NorthWestern spokesman Butch Larcombe said. “It’s just kind of a chance to talk to the people at the dams and get a look at what goes on inside.”
Read more at The Missoulian