A 118-year-old dam about five miles below the summit of Monarch Pass is about to be decommissioned and the dam removed. Xcel Energy said the dam and Unit 1 of the company’s two-generator Salida Hydro Generating Station near Mayville, because of its age, is too expensive to maintain.

Retirement of the Unit 1 generator is expected to take place from this summer through fall of 2025.

Unit 2 of the Salida Hydro Generating Station will be retired in 2027.

The 218-foot, earth-and rock fill dam on Fooses Creek near its confluence with the South Arkansas River holds a small amount of water from an upstream diversion dam on the river and directs it down to the power station. The dam and power station were built in 1906 to power local mining operations. The generators were replaced with more efficient ones in 1929.

The system is called a “run of river” system that relies on seasonal water flow in the river rather than storing water for continuous generation.

The 2024-2025 project includes removing 4,806 feet of gravity flow pipeline from the Garfield diversion dam upstream and most of the 8,080 foot penstock pipeline from the Fooses Dam to the Unit 1 powerhouse.

Colorado Parks and Wildlife and U.S. Forest Service biologists will relocate fish from the reservoir using electrofishing and trap netting before transferring them downstream to ensure their survival.

“The project is anticipated to last from July 2024 to December 2024. Fishing will be prohibited during construction. Xcel Energy is coordinating with Colorado Parks and Wildlife to ensure that fish are handled responsibly during the water removal process,” according to a U.S. Forest Service release.

For more information about the project, visit the Xcel Energy Salida Hydro 1 Generating Station Decommissioning Project website.