Protecting Minnesota Water Quality

WaterLegacy has focused for over a decade on protecting clean water by supporting Tribal authority under the Clean Water Act, working to hold regulators accountable, and advocating to preserve and strengthen specific water quality standards to protect wild rice, aquatic life, and human health, and to restore waters impaired by pollution.

St. Louis River, Jay Cooke State Park. Photo by Bryan Hansel, www.bryanhansel.com

Defending the Clean Water Act

On January 5, 2026, WaterLegacy submitted a letter to the U.S. Environmental Protection Agency and U.S. Army Corps of Engineers expressing opposition to proposed 2025 rule changes to constrict the Waters of the United States (WOTUS) that would be protected under the Clean Water Act.

The 2025 Proposed WOTUS Rule would sharply narrow Clean Water Act constraints on pollution, draining, and filling of wetlands and small streams. Millions of acres of wetlands and countless small streams would lose protection, leaving them vulnerable to contamination and destruction. If finalized, the proposed rule would dismantle decades of protections and put drinking water, wildlife habitat, human health, and ecosystems at risk in Minnesota and across the nation.

Tribal Clean Water Act Authority

Since 1987, federally recognized Tribes have had the right to apply for and obtain Treatment as a State authority under the Clean Water Act. WaterLegacy’s Advocacy Director and Counsel, in consultation with tribal staff, published a path-breaking article on tribal authority to veto or condition federal permits that affect water quality. WaterLegacy has supported tribal work to strengthen protection of Reservation waters.

Controlling Toxic Pollutants

WaterLegacy has worked to preserve and strengthen water quality standards that protect aquatic life and human health. WaterLegacy prevented the weakening of Minnesota standards for manganese, a pollutant in drinking water that causes harm to the brain, particularly in infants, children, and the elderly. We’ve worked to require mercury limits in permitting to protect human health. WaterLegacy has also worked with Minnesota and national scientists to develop and share research that supports the need to protect aquatic life from specific conductance pollution, a combination of salts and ions released in the mining process.

Restoring Impaired Waters

In order for polluted waters to be restored, they must first be listed as impaired, then studied through a total maximum daily load (TMDL) study to determine the causes of the impairment. WaterLegacy has advocated for listing of impaired waters, TMDL studies, and restoration of Minnesota waters, particularly wild rice waters impaired due to sulfate pollution and waters impaired due to high levels of mercury in the water column or in fish.

MPCA Failure to Regulate

In July 2015, WaterLegacy took a more systemic approach to Minnesota failure to regulate mining pollution, submitting a petition to the U.S. Environmental Protection Agency (EPA) to remove Minnesota’s Clean Water Act authority due to the Minnesota Pollution Control Agency’s (MPCA) failure to control mining pollution.