The Chisago Lakes Chain of Lakes watershed in southern Chisago County is made up of 18 lakes and outlets to the St. Croix River through the Sunrise River. The top 20 urban and rural projects around North and South Center Lakes that are identified in the Rural Subwatershed Assessment and Urban Stormwater Retrofit Analysis reports will be the top priority of this application. The goal is a phosphorus reduction of 100 pounds (4%) to North and South Center Lakes.
The Mallery Jerseys dairy farm is critically located along the bluff of the St. Croix River escarpment and drains directly to the St. Croix River. In 2018, a Comprehensive Nutrient Management Plan was completed and identified a number of additional practices that should be implemented to improve the water quality of the St. Croix River. The proposed practices will reduce the phosphorus and nitrogen by 76 pounds (83%)and 265 pounds (85%) respectively.
A large, actively eroding gully has existed on the campus of Parmly, a senior living complex in Chisago City, for at least 50 years. The gully is on the banks of Green Lake, which is at high risk for becoming impaired in the near future. The Parmly gully project is identified as a source of untreated stormwater and phosphorus loading in the Chisago City urban subwatershed retrofit analysis report. Stabilization of the gully will provide a 20% reduction in phosphorus loading to Green Lake. The staff of Parmly is in full support of the project and a design is complete.
The St. Croix River escarpment has been a focal point for the Chisago Soil and Water Conservation District over the past 8 years, and continues to be one of the leading areas of Chisago County in terms of phosphorus reduction projects to Lake St. Croix. Of the original inventory, 16 of the 36 gullies have been stabilized. This application includes the stabilization of 5 gullies. These projects will reduce the phosphorus loading to the St. Croix River by at least 50 pounds per year and sediment loading by at least 50 tons per year.