Xcel starts $50M upgrade of hydroelectric dam near Menomonie

Work is starting on the first phase of a $50 million project to upgrade Xcel Energy‘s more than century-old Ceder Falls hydroelectric dam in Menomonie, the utility announced last week.

Improvements to the structure will bring the 7.1-megawatt dam into compliance with federal standards. Xcel is starting work on the project after earning approval from the Wisconsin Public Service commission last year. The Cedar Falls dam, first built in 1910, sits on the Red Cedar River and creates the 1,800-acre Tainter Lake, a popular recreation destination north of Menomine.

The utility began working on the project after learning the existing dam wouldn’t meet federal flood-resiliency guidelines, according to Barr, the project’s engineering firm.

The project team worked with the St. Anthony Falls Hydraulics Laboratory at the University of Minnesota to build a 1/36th scale model of the project and confirm that improvements would measure up to federal standards.

“The results of this physical model study helped us create a plan that minimizes costs of the improvements while modernizing a spillway that meets modern day standards,” said Rob Olson, manager of hydro operations at Xcel. “This will help extend the life of the facility way into the future.”

The project calls for replacing an existing overflow spillway and small gates with six large gates. The upgrade would also add a downstream stilling basin to reduce the risk of eroding the riverbed at the dam. Crews plan to build the improvements in phases using upstream and downstream cofferdams.

Tainter Lake is expected to stay at its normal water level throughout the three-year construction project. Xcel said the project is part of an ongoing effort to source more of its energy from carbon-free sources. The Minneapolis-based utility has pledged to go carbon-neutral by 2050. Each of Wisconsin’s investor-owned utilities have also pledged to meet that goal.

The Cedar Falls dam is one of 19 hydroelectric dams Xcel operates in Wisconsin that produce a combined 265 megawatts of power.