New reports by the Minnesota Pollution Control Agency (MPCA) detail impairments affecting recreation, and fish and aquatic insect communities in the Redwood River Watershed in southwestern Minnesota. The reports recommend building upon many actions local groups have already taken to address water quality in the watershed.
Since 1994, local partners have invested more than $9 million implementing best management practices, water monitoring, and educational programming that have reduced sedimentation by more than 27,276 tons per year. Excessive sediment is the root cause of many water quality impairments in the watershed.
The reports outline impairments and highlight additional restoration and protection strategies.
Impairments
Streams – Biologists assessed 35 of the 42 stream reaches in the watershed. Seven fully support aquatic life (fish and bug communities) while 28 do not due to poor habitat related to a variety of causes, notably excessive sediment. All 13 reaches assessed for recreation did not support state water quality standards for E. coli bacteria.
Lakes – The MPCA assessed 8 of 23 lakes in the watershed for recreation and only 2, West Twin and East Twin lakes, met water quality standards and are key lakes to protect. A reclamation project was completed in 2022 to restore Lake Redwood by removing accumulated sediment and increasing its depth. The project is expected to: treat impairments in the Minnesota River by trapping up to 16,500 tons of sediment and 11 tons of phosphorus annually, increase reservoir capacity for hydroelectric power generation for the City of Redwood Falls, and enhance fisheries habitat and regional recreational opportunities.
Protection strategies
The MPCA and its partners identified several strategies to build upon efforts by the Redwood Cottonwood Rivers Control Area and soil and water conservation districts that have already resulted in water quality and habitat improvements (see MPCA Healthier Watersheds Accountability Report). These strategies/projects include:
- Grade stabilization structures and practices (e.g., water and sediment control basins, grassed waterways) in high-sloped areas, which include two designated DNR trout streams (the Redwood River in Camden State Park, and Ramsey Creek near Redwood Falls).
- Soil health education and outreach
- Restore and protect lakes and stream reaches with high recreational use and value (Lake Benton and Norwegian Creek, Redwood River in Camden State Park, Lower Ramsey Creek).
- Restore and protect lakes and stream reaches that are nearly impaired or barely impaired in Three Mile Creek and Clear Creek, School Grove Lake, West Twin Lake, and Sanderson Lake.
- Protect vulnerable and sensitive groundwater areas.
TMDL and WRAPS reports
One recently released report is a total maximum daily load (TMDL) study. A TMDL establishes the amount of each pollutant that a water body can accept and still meet water quality standards. The TMDL also estimates the amount of reductions needed to meet the standards. TMDLs are required by the federal Clean Water Act.
The second report, a watershed restoration and protection strategy (WRAPS) report, is required by the state Clean Water Legacy Act and uses TMDL reports, monitoring results, and other information to develop strategies for restoring polluted waters and protecting healthy ones. Local partners will use this information to develop detailed implementation plans and set priorities for projects.
The MPCA invites the public to share feedback on these reports including suggestions for additional or revised protection and restoration strategies as they relate to aquatic life and aquatic recreation. The draft reports are available on the MPCA’s website: Redwood River Watershed.
Comments may be submitted online at Public Comments or by US mail to the following address: Minnesota Pollution Control Agency; c/o Michael Weckwerth; 504 Fairgrounds Road; Marshall, MN 56258. Submit your comments by March 23, 2023.
Comments must include a statement of your interest in the report(s), and the action you are requesting from the MPCA, including specific changes to sections of the draft report(s) and the reasons for making those changes.