Lowering the Lakes: the Environmental, Economic and Recreational Impacts of Returning Lake Mendota to Historical Levels

Abstract

After extensive flooding in the Madison, Wisconsin area in August 2018, there have been calls by the public to permanently lower the largest body of water in the region, Lake Mendota, which has been artificially raised 5 feet by a dam, in order to prevent potential future floods. To investigate the practicality of lowering the lake, we first conducted a historical analysis of Lake Mendota’s previous water levels in order to provide contextualization of our research. We then used geospatial modeling to produce maps simulating what would happen to Mendota’s shoreline and navigable areas if the lake were lowered by 1, 2.5, or 5 feet from current average summer levels. These maps were then utilized in a series of interviews to facilitate discussion with several key stakeholders on the levels of Lake Mendota, as well as during a survey of the general public. We conclude that financial cost, navigability and accessibility, ecology, and potential effectiveness of future flood mitigation are the primary concerns in this issue, and that extensive future research and education of the public regarding the lakes is necessary before proceeding with any action.