Wisconsin is experiencing an increase in dam failures, highlighting the intensifying storms affecting the region.
According to a report shared on Thursday by the Wisconsin Policy Forum, the state has documented 34 dam failures between 2000 and 2023, ranking second only to South Carolina in the U.S. During this timeframe, over 80% of these failures—specifically, 28—occurred since 2018, with 18 of those incidents transpiring since 2020. Fortunately, none of these failures have led to fatalities, as indicated by the findings in the report.
Home to more than 4,000 dams, Wisconsin’s landscape features a mix of large hydroelectric facilities and smaller earthen structures, which are often used to create farm ponds. Ownership of these dams is diverse, involving private companies, individual landowners, government agencies, tribal entities, and utility companies.
According to the National Inventory of Dams maintained by the U.S. Army Corps of Engineers, Wisconsin contains 1,004 dams, varying in height from 6 feet to the 92-foot-tall Flambeau Dam located on the Dairyland Reservoir in Rusk County.
The inventory identifies over 200 dams as having high hazard potential, implying that if these dams were to fail, there could be potential fatalities. Out of the 34 recorded dam failures in Wisconsin over the past 23 years, three were classified as high hazard potential. One was deemed to have significant hazard potential—suggesting potential for economic loss, environmental damage, and other issues—while the majority, 18 dams, were assessed as having low hazard potential, indicating that their failure would likely result in no loss of life along with minimal economic and environmental repercussions. The hazard potential for the remaining dams remains unknown.
Since 2009, state budgets have allocated a minimum of $4 million annually for dam safety initiatives. While this funding has allowed for improvements to crucial dams within the state, the report warns that the impacts of a changing climate—resulting in more frequent and severe extreme rainfall—may present new challenges for Wisconsin’s dam structures.
The report was put together by the Wisconsin Policy Forum and utilizes data sourced from the Association of State Dam Safety Officials.
