Water Quality Improvement Projects

Three Rivers Park District’s Water Resources Team is committed to improving the water quality of lakes located within the parks. Staff is regularly checking lakes in the Park District for any water quality concerns. If concerns are identified, a course of action is planned and carried out to improve the water quality.

View of clear water at lake shore

Gale Woods Farm

Whaletail Lake, which can be accessed from Gale Woods Farm, was listed on the Minnesota Pollution Control Agency’s impaired waters list for excessive nutrients (south basin in 2006 and north basin in 2008). The lake currently has high phosphorus concentrations and poor water clarity due to summer algae blooms.  In 2017, Pioneer-Sarah Creek Watershed Management Commission (PSCWMC) and Three Rivers Park District completed a study (Pioneer-Sarah Creek Watershed Total Maximum Daily Load)  to identify sources of nutrient loading that affected the surface water quality of the lake. The study determined that nutrients, primarily phosphorus, are being recycled from the sediments of the lake to the surface accounting for 80% of the phosphorus load affecting the water quality in the south basin.

Since the study was completed, the north basin has noticeably improved and is currently meeting state water quality standards. The south basin, however, continued to have impaired water quality conditions. To bring the south basin of Whaletail Lake into compliance and ensure that the north basin will continue to meet the state water quality standards, Three Rivers Park District has planned an alum application, which will be applied as two separate treatments occurring in the spring of 2023 and 2024, to address long-term control of internal phosphorus loading. Alum has a strong binding capacity that prohibits the release and recycling of phosphorus into the surface water column. Alum is a benign and safe product that has been successfully used on other Minnesota lakes to improve lake water quality conditions.

This partner project involves several different agencies and will be completely funded through a Board Water and Soil Resources Clean Water Legacy Fund grant, with contributions from Pioneer-Sarah Creek Watershed Management Commission, the City of Minnetrista and Three Rivers Park District. The project will improve water quality conditions to achieve in-lake water quality standards for the south basin, including improved water clarity conditions with less frequent summer algal blooms. The improved water quality conditions will benefit the aquatic plant and fish communities on the lake.

Sochacki Park

Three Rivers Park District, in coordination with Golden Valley, Robbinsdale, and the Bassett Creek Watershed Management Commission, is assessing the sub-watershed in Sochacki Park to identify potential improvements to its wetlands. The assessment is the first step toward improving the ecological health, aesthetics and condition of the wetlands and providing additional outdoor recreation and education opportunities. 

Phase 1 of the Sochacki sub-watershed assessment is now complete. For the past two years, Water Resources staff tracked water quality through monthly sampling, conducted vegetation surveys, analyzed sediment and monitored storm water entering the wetland ponds. View a summary of the data collected in 2021. This body of monitoring data will be incorporated into calibrated watershed and wetland models used to examine pollutant loading and to develop best management practices for improving water quality. A wetland function and values assessment was also completed under phase 1. View a summary of these findings.

Ponds within the park, North Rice, South Rice and Grimes, are classified as shallow wetlands by the Minnesota Department of Natural Resources. As part of the two cities’ stormwater management systems, these ponds receive runoff from the surrounding areas before draining into Bassett Creek. Common to wetlands in urban areas, the ponds have high amounts of nutrients that contribute to water quality problems, prompting concern from residents and park visitors. A project steering committee, including staff from the partner agencies, the consulting engineer, and a neighborhood citizen liaison, is meeting quarterly to help guide the process.

The next phase of the project, which is taking place in 2022, includes developing a sub-watershed assessment report that will outline realistic water quality goals and identify actions to reduce pollutant loading and improve wetland health. The project steering team will review the report and share the recommendations with partners and stakeholders this summer before developing an implementation plan and schedule. A summer 2022 project update is available here.

A  summary of data collected in 2020 is available here, and a spring 2021 project update that describes the work that took place in the first year of the study is available here.

Sochacki Park includes land in Robbinsdale and Golden Valley and is jointly operated under a partnership between Three Rivers Park District and the Cities of Golden Valley and Robbinsdale. The park entrance is located at 3500 June Ave. N., Robbinsdale. For more information about the sub-watershed assessment, check out these Frequently Asked Questions, or contact Jami Markle, Three Rivers Park District Director of Natural Resources, at 763-694-7841 or Jami.Markle@ThreeRiversParks.org.

Fish Lake Regional Park

Fish Lake covers 238 acres, offering fishing, boating and swimming to park visitors and area residents. In 2008, the lake was listed on the state’s impaired waters list for excess phosphorus. Excess phosphorus causes algae blooms that turn the water green which negatively affects the suitability of the lake for humans, pets and even wildlife.

Together with the Elm Creek Watershed Management Commission and the Minnesota Pollution Control Agency, Three Rivers’ staff conducted water quality studies at Fish Lake. These studies found that most of the phosphorus affecting the lake’s surface water was being released by enriched sediment at the bottom of the lake. Three Rivers worked with the City of Maple Grove, the Fish Lake Area Residents Association, and the Elm Creek Watershed Management Commission to pursue a strategy to correct the problem and bring the lake into compliance with state water quality standards.

On behalf of the Watershed Commission and with the support of the partners, Three Rivers submitted a grant application through the state’s Clean Water Fund program to treat Fish Lake with a chemical compound called alum. The grant was approved and alum treatment has begun. Alum is commonly used in the kitchen for pickling and by water treatment facilities for treating drinking water. When applied properly, it is safe to use in a lake to control phosphorus released by lake bottom sediment.

Lake Rebecca Park Reserve

Lake Rebecca was listed on the state’s impaired waters list in 1998 for excessive mercury and again in 2008 for excess phosphorus. Three Rivers staff worked with Hennepin County Environmental Services to improve manure and stormwater management by a livestock operation in the lake's watershed. Three Rivers also used several different methods to treat stormwater from developed areas within the park. In 2009, Three Rivers staff launched efforts to control the invasive curly leaf pondweed, which is known to damage water quality. And finally, Three Rivers staff carried out an alum treatment on the lake to dramatically reduce the release of phosphorus from highly enriched bottom sediments.

Water quality in the lake has dramatically improved, and the public, as well as regulatory agencies, has noticed. Because of these efforts, Lake Rebecca will soon be removed the state's "impaired waters" list, the first lake in Three Rivers Park District to achieve that distinction.