Holter Dam: Power on the Missouri

North of Helena, the Missouri River drops through a canyon and hits Holter Dam, one of several dams built to harness the upper Missouri's power. Holter was completed in nineteen eighteen by the Montana Power Company, joining Hauser Dam just upstream. The canyon itself was named by Meriwether Lewis in eighteen oh five, who called the passage the gates of the rocky mountains in his journal.

The dam created Holter Lake, a reservoir popular with boaters and anglers today. For most of the twentieth century, these dams supplied electricity to Helena, Great Falls, and the copper mines and smelters in Butte and Anaconda, making them the quiet infrastructure behind Montana's industrial economy.