4.3 Water Quality

Goal 3 - Water Quality

Preserve, maintain and improve aesthetic, physical, chemical and biological composition of surface waters and groundwater within the District.

Discussion

The HHPLS used an extensive public input process to establish water quality goals for the primary receiving waters in the District, focusing primarily on identifying target total phosphorus concentrations.  This plan identifies those goals plus additional goals related to water quality.  This plan sets forth a set of actions the District will undertake to reduce pollutant loading in the subwatershed and achieve water quality goals.  The achievement of these water quality goals is not only necessary to meet state and federal water quality requirements and to prevent future TMDLs, but also to meet this plan's ecological integrity goals. 

Desired Outcomes: Achievement of in-lake nutrient concentration goals through achievement of nutrient loading reductions.

Metrics:

  • In-lake nutrient concentrations/Trophic State Index Scores (TSI) for Lakes Minnewashta and Virginia, and in-lake nutrient concentrations for Tamarack and St. Joe
  • Nutrient loading goals (lbs) for Lakes Minnewashta and Virginia

Goal 3.1 - Lake Virginia

Achieve the in-lake total phosphorus concentration goal of 20 ?g/L in Lake Minnewashta.

Actions

  1. Require LGUs to reduce phosphorus loading from residential and other uses upstream of Lake Minnewashta by a minimum of 38 pounds per year within 10 years.
    1. Provide education and training opportunities, technical and planning assistance for property owners and LGUs on methods to reduce phosphorus and sediment loading by incorporating BMPs into landscaping, agricultural and horticultural practices, infrastructure maintenance, and reconstruction.
    2. Consider developing a small grant program to provide financial assistance to property owners desiring to retrofit their property with BMPs to reduce phosphorus and sediment loading.
  2. Provide assistance to LGUs and developers to foster low impact development and redevelopment that minimizes new phosphorus and sediment loading.
    1. Develop and distribute model ordinances and design standards that incorporate low impact design principles.
    2. Sponsor educational opportunities for LGU staff, developers, elected and appointed officials and other interested parties to provide practical information and opportunities for sharing experiences.
  3. Work cooperatively with the Minnesota Landscape Arboretum and Horticultural Research Center to identify ways to reduce phosphorus loading from the upstream subwatershed units.
  4. Continue regular water quality monitoring in Lake Minnewashta to assess progress toward achieving the in-lake phosphorus goal.

Goal 3.2 - Lake Virginia

Achieve in-lake total phosphorus concentration goal of 40 ?g/L in Lake Virginia.

Actions

  1. Require LGUs to reduce phosphorus loading from residential and other uses upstream of Lake Virginia as identified in the HHPLS by a minimum of 24 pounds per year within 10 years.
    1. Provide education and training opportunities, technical and planning assistance for property owners and LGUs on methods to reduce phosphorus and sediment loading by incorporating BMPs into landscaping, agricultural and horticultural practices, infrastructure maintenance, and reconstruction.
    2. Consider developing a small grant program to provide financial assistance to property owners desiring to retrofit their property with BMPs to reduce phosphorus and sediment loading.
  2. Provide assistance to LGUs and developers to foster low impact development and redevelopment that minimizes new phosphorus and sediment loading.
    1. Develop and distribute model ordinances and design standards that incorporate low impact design principles.
    2. Sponsor educational opportunities for LGU staff, developers, elected and appointed officials and other interested parties to provide practical information and opportunities for sharing experiences.
  3. Achieve and maintain the Lake Minnewashta in-lake phosphorus concentration goal to reduce phosphorus contributed to Lake Virginia.
  4. Continue regular water quality monitoring in Lake Minnewashta to assess progress toward achieving the in-lake phosphorus goal.

Goal 3.3 - Lake Virginia

Prevent degradation of the long-term average in-lake total phosphorus concentration in Lakes Tamarack and St. Joe.

Actions

Recruit, train, and retain citizen volunteer monitors for each lake and monitor at least every other year through the Metropolitan Council Citizen-Assisted Monitoring Program.

Goal 3.4 - Lake Virginia

Achieve and maintain other state water quality standards including >1.4 m Secchi clarity, 14 ug/L chl-a, TSI <57 in Lakes Minnewashta and Virginia.

Actions

  1. Achieve and maintain in-lake total phosphorus goals.
  2. Manage aquatic vegetation in accordance with a vegetation management plan that takes into account water clarity goals.
  3. Develop a water quality index which encompasses the District's broader definition of water quality.

Goal 3.5 - Lake Virginia

Minimize pollutant loading contribution to Smithtown Bay from the subwatershed.

Actions

  1. Achieve Lakes Virginia and Minnewashta in-lake total phosphorus concentration goal.
  2. Promote the general application of BMPs across the subwatershed.
    1. Consider developing a small grant program to provide financial assistance to property owners desiring to retrofit their property with BMPs to reduce phosphorus and sediment loading.