Shields Lake Stormwater Harvest, Irrigation Reuse,
and Alum Treatment Project
This is a multi-phase project that greatly reduces phosphorus loads to Shields Lake, and subsequently Forest Lake. Phase 1 of the project included impounding/harvesting water from a tributary to Shields Lake for irrigation reuse by Forest Hills Golf Course. The impounding of surface flow reduces the watershed phosphorus load by 77-94 pounds/year, and the irrigation reuse will reduce the amount of groundwater being used for irrigation by up to 26 million gallons per year. Phase 2 of the project included a whole-lake alum treatment to Shields Lake which has reduced internal sediment phosphorus loading to natural background levels. Post-project water monitoring has shown that the combination of the irrigation reude system and alum treatment has reduced phosphorus loads to Shields Lake by >1,000 lbs/yr and Forest Lake by >500 lbs/yr. These improvements are expected to allow Shields Lake to achieve its long-term lake water quality goal and a clear water state.
This project was identified as a result of the Shields Lake Diagnostic Study.
- 2021 Project Spotlight Video
- Past Project Spotlight PowerPoint Slides
- 2020 MAWD Presentation | Video Recording
- 2018 Project Open House - Powerpoint Presentation
- News: 2017 brings more than $2 million in Clean Water Funds to Washington County
- Shields Lake Diagnostic Study - 2016 Technical Memo