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Lake Wissota Hydroelectric Dam

Operating in 1917 and completed in 1918, the Dam harnessed the Chippewa River, Yellow River, and the creeks of O'Neil, Paint, and Stillson. This created a 51-mile shoreline, 6,212-acre lake reservoir to provide the fall and water storage to turn turbine/generators in the powerhouse. At the time, it was claimed to be the "greatest hydroelectric dam on the American continent." To name the dam and man-made lake, the Wisconsin-Minnesota Light and Power Company engineer, L. G. Arnold, consolidated those two state names into the shorter "Wissota."

The enormous construction undertaking of its day required building a temporary, adjacent village - later named Wissota Hamlet - with typical facilities including houses, dining hall which fed 350 workers at a time, school and hospital to care for the 700 workers and families. And, it meant the farms inside the area to be flooded, and such things as the Yellow River Bridge (now the Cobban Bridge located 15 miles upstream on the Chippewa River), had to be vacated, moved elsewhere, or abandoned.

Five million dollars was the estimated project cost. The 13 Stauwerke automatic gates were an important feature of the 900-foot concrete spillway with each being 64 feet long and nine feet high. When the dam was constructed these gates were designed to hold the water level above the dam within one foot during the greatest river run-off. Over the years of operation when river flows are high, the water level range can exceed well beyond the designated one foot operating range of the Stauwerke gates. The entire dam being over 6,900 feet long, two additional dikes made it even longer. With the six hydroelectric turbines installed in the hydro plant, the generating capacity could reach 36.4 megawatts.

One concern, while the water level gradually rose as the reservoir filled, was what would happen to the trees that remained on the lake bottom. When the first winter came, so did the answer. Ice formed around the trees and as the water continued to slowly rise, the trees were frozen in ice that refused to give up its grip. The rising water lifted the ice and slowly pulled the trees up by the roots. Locals farmers, noticing the unusual opportunity, drove into the ice and harvested the trees. And one very nice stand of pine on the west side of the lake was sold, cut from the ice, and turned into some fine lumber.

Though workers built the Wissota Dam by hand, horse-driver equipment and with tools of more than 100 years ago, today that dam is still considered exceptional having needed no major changes in design, construction or operation according to the owner Xcel Energy.