Low Impact Development Demonstration Project
Lake Superior Shoreline,
Lake Superior Association of Soil & Water Conservation Districts
Basin Program Funds:
Tourism, recreational development and the turnover of property ownership along Minnesota’s Lake Superior shoreline are increasing at a rapid rate. Development of the lakefront in many areas has accelerated shoreline erosion and other nonpoint source pollution, typically by the removal of vegetation and the increase and concentration of storm water runoff. Development typically causes an imbalance in the natural hydrology of a watershed. As the amount of impervious surfaces increase (e.g. addition of rooftops, parking lots, roads, etc.), more water runs off the land directly into Lake Superior and into storm sewers discharging to the lake, instead of infiltrating into the groundwater.
In an ongoing effort to reduce nonpoint source pollution and soil erosion along the shore of Lake Superior, the Lake Superior Association of Soil and Water Conservation Districts (LSA), together with the Board of Water and Soil Resources (BWSR) and the SWCD Joint Powers Board (JPB) Area 3, have worked to educate developers, new shoreline property owners and local government units about shoreline erosion and other nonpoint pollution issues. These include both human activities (e.g. construction and runoff, septic systems, vegetation management, etc.) and natural shoreline erosion that together create critical water quality concerns, including water supply contamination and aquatic habitat impacts. The project team has completed approximately 30 shoreline erosion control projects since 1994 and many more nonpoint pollution control projects within the coastal region of Lake Superior. Shoreline best management practices (BMPs) have been developed and are actively promoted to address these issues and concerns.
Demonstration projects have been highly successful in promoting shoreline BMPs. Much more can be done with respect to development issues along the Minnesota Lake Superior shoreline. Innovative storm water management is becoming increasingly important. Recently completed storm water management plans in Two Harbors and Grand Marais, Minn., identified the need for low-impact development in response to current storm water runoff issues related to impervious surfaces.
The goal of this project is to provide the LSA/JPB/BWSR technical team, shoreline landowners, developers, contractors and local government units with practical information on selecting and installing low-impact development methods and products in our region. This project will first focus on reviewing current literature on low-impact development methods and products and on guidelines for their selection. Then, the project team will evaluate several potential demonstration sites and select one or more for the installation of one or more low-impact development methods. After installation, the site will be periodically monitored to assess the effectiveness of the installed practices. A post-construction workshop will be held to share valuable information learned through the demonstration project(s). Many future project sites will benefit from the information gathered as part of this investigation.
The literature review and project site selection process were completed in fall/winter 2002.
After reviewing eight potential project locations, the Glensheen Historic Mansion, operated by the University of Minnesota, was selected for our low impact development (innovative storm water management) demonstration project. (Initially, two project sites were selected: Glensheen Historic Mansion and Split Rock Lighthouse Visitors Center. No project funds were used at Split Rock because of a combination of project timing problems and cost estimates for the Glensheen Project.) The project design work, project plans and specifications were completed for the Glensheen Project in February 2004 and construction was completed in June 2004. The final constructed project included:
Glensheen is a highly visible public property visited by thousands of people each year. A workshop was held June 11, 2004 to disseminate results from the project. The project was a great success. Our project workshop was attended by 50 people, including many design engineers and developers. We are certain that the lessons learned through this grant will provide region-specific low-impact development tools, which will improve overall water quality and provide valuable benefits to the Lake Superior watershed.
- A 100’ grassed swale near tool shed with one rock check
- A 185’ grassed swale in parking lot with two rock checks (routes runoff to bioretention area)
- Vane drain through paved area (routes runoff to bioretention area)
- Bioretention runoff treatment area
- Two rock chutes to beach (route treated water from bioretention area and grassed swale near tool shed)
Contact: Mr. R. C. Boheim, 218-723-4867