Those Dammed Wisconsin Rivers

Of the 2.5 million dams in the United States, 3,800 are located right here in the state of Wisconsin. Most of the dams are small, privately owned structures. When early settlers arrived in our region, they quickly grasped the advantages of putting the aquatic landscape to work for them. In an epic tale of man versus nature, these industrious newcomers began to divert and restrain the state’s mighty rivers and tributaries, and impound massive artificial lakes. By harnessing the water in this way, they were able to transport raw materials and people more efficiently, and provide a reliable source of hydropower for sawmills and, later, paper mills, flour mills, machine shops, foundries and factories. These dams encouraged and provided for early settlement in Wisconsin.

According to the Wisconsin Department of Natural Resources, the state’s first dam was built in 1809 to provide power for a sawmill on the Fox River near De Pere. Christine Macy’s book Dams features a number of notable Wisconsin dams in its collection of 800 historical and contemporary photographs of dams built in America between the 1930s and the 1970s. One unique work of engineering featured in the book is the Cedar Falls Dam on the Red Cedar River in northern Dunn County.

During the 19th century, the Red Cedar River served as a logging run for the largest lumber producer in the country, the Menomonie-based Knapp, Stout & Co. According to Macy, the river was dammed in Menomonie as early as 1848, and a similar wood-crib structure upstream at Cedar Falls powered a sawmill.

In the 1890s, growing industrial demand for electrical power inspired investors to build hydroelectric dams that hold back and divert a river’s flow through a powerhouse. In basic terms, the falling water runs through propeller-like turbines, causing them to rotate. The rotation of these turbines spins generators to produce electricity. The volume of water flow and the height from the water surface at the dam reservoir to the water surface downstream largely determine the amount of electricity generated from each unit.

In 1910, the original dam in Cedar Falls was replaced with a concrete structure 510 feet long and 65 feet high. With the exception of new generators installed in 1912 and 1915, it has remained largely unchanged. Xcel Energy, a public utility company based in Minneapolis, currently owns the Cedar Falls Dam, and operates a modified run-of-the-river hydroelectricity project, which impounds Tainter Lake and generates 6.8 megawatts of hydroelectric power.