About Alliant Energy
- Company Information
- Our Environmental Commitment
- For Investors
- For Shareowners
- Doing Business With Alliant Energy
- Social Media
A brief history of the dam
The Prairie du Sac Dam, located about one mile north of Prairie du Sac, Wis., will celebrate one hundred years of operations in September 2014. The hydroelectric facility has a rich history in providing energy to area residents, spurring economic growth across the region, and helping to launch Alliant Energy’s Wisconsin utility – Wisconsin Power and Light Company.
Building a structure the size of the dam in the early 1900s was no easy task but ground was broken for the project in 1911. To transport materials to the site, the railroad was extended and a construction camp was built on the west bank of the Wisconsin River for the large number of required workers. Building the dam brought numerous challenges. Flooding in 1911 and 1912, and an ice break up in 1913 damaged the construction site. Despite these setbacks, the power plant began producing renewable energy in 1914.
Wisconsin Power and Light Company - then known as Eastern Wisconsin Electric Company - purchased the Prairie du Sac Dam in 1917 and has owned and operated the hydroelectric facility ever since. While the 31-megawatt power plant is small by today’s standards, when it was built it was one of the largest sources of electricity in the Midwest.
The birth of Lake Wisconsin
While the dam has been a consistently reliable source of electricity for a century, an equally important contribution is that its construction formed Lake Wisconsin. This 10,000 acre lake is a very popular tourist attraction that offers 52 miles of shoreline. The beginnings of Lake Wisconsin and the Prairie du Sac Dam will be forever linked with both marking important milestones together.
Join the celebration
To commemorate the Prairie du Sac Dam’s 100th anniversary, as well as the birth of Lake Wisconsin, Alliant Energy and several organizations in the Sauk Prairie area are involved in multiple historic, educational and fun events. The details for these events are evolving so we encourage you to come back often and visit the 100th Anniversary Celebration Schedule of Events Page.