3.1 Water Quality

  1. Lake Minnewashta currently has excellent water quality, although it slightly exceeds the total phosphorus concentration goal established in the HHPLS.   It meets state standards for total phosphorus, clarity, chlorophyll-a, and Trophic State Index (TSI).  Lake Virginia exceeds its total phosphorus goal, but meets or nearly meets clarity, chlorophyll-a, and Trophic State Index (TSI) goals.   Lake Virginia is listed as an Impaired Water for excess nutrients, and a TMDL study is being completed as a result.  Limited data is available for Tamarack Lake and Lake St. Joe, and no total phosphorus goal was established in the HHPLS.
  2. Future development is not expected to significantly impact Lake Minnewashta.  Some developing areas drain to Virginia and Tamarack, and nutrient and TSS loads as well as volume of stormwater runoff are predicted to increase as a result, potentially further degrading water quality in Lake Virginia.