The Stormwater Management & Flood Mitigation Study is now complete and was accepted by both the Prior Lake City Council and the Prior Lake-Spring Lake Watershed District Board of Managers in December 2016.
The Study was initiated two years ago as a result of the 2014 flood. The Study was sponsored by the Prior Lake-Spring Lake Watershed District and City of Prior Lake in collaboration with Spring Lake Township; Barr Engineering served as the consultant. The Study was comprised of four project phases: 1. Update the Watershed’s Model 2. Identify Flood Reduction Options 3. Evaluate Flood Reduction Options and 4. Develop an Implementation Plan.
Policymakers representing the three entities agreed upon four goals: Protect public safety and maintain emergency access; protect public utility infrastructure; maintain traffic flow through the County Road 21 corridor and maintain access to private properties.
Out of an initial list of 20 alternatives, the policymakers selected three to implement. They are: actively manage the Prior Lake Outlet; enhanced protection and secure upper watershed storage.
Actively managing the Prior Lake Outlet is considered a short-term goal and is the responsibility of the District. The District will create a process to analyze weather forecasts, storage capacity of existing wetlands and lakes and the flooding potential as part of updating its procedure to open the Outlet Structure’s low-flow gate. Currently, the District is only authorized by the Department of Natural Resources to open the low flow gate in response to snowmelt in the spring.
Enhanced protection is a short-term goal, as well. The City of Prior Lake will lead efforts to coordinate temporary enhanced protection measures during flood events. The City will develop a written policy which will be reviewed and adopted by the City Council.
Securing upper watershed storage is a long-term goal. This goal will identify potential storage areas that could provide flood damage reduction as well as provide water quality improvement benefits. The storage areas will be carefully considered with a key factor which includes the willingness of landowners to participate in a program to create storage areas.
A copy of the complete Stormwater Management and Flood Mitigation Study is available on our website along with other information about the project.