The St. Louis River Watershed which drains to the St. Louis River and its associated estuary near Lake
Superior has more than 150 years of human development history since Euro‐Americans first settled
there, resulting in critical water quality impacts. In 1987, the U.S. Environmental Protection Agency
designated the St. Louis River as an Area of Concern primarily due to that history which entailed
inappropriate discharge of untreated wastewater and debris from poor industrial and community
practices. The organic matter loading from inadequate treatment of sewage and paper mill products
along with the dumping of woody debris from sawmills contributed to low oxygen levels in the river. The
result included devastating impacts to the entire food web from the bacteria to vegetation to
invertebrates to fish. Concurrently, poorly managed stormwater runoff from this post‐logged, barren
landscape contributed excessive loading of suspended sediments resulting in increased turbidity and
nutrient concentrations (e.g., phosphorus, nitrogen) to the river. Since then, government and private
entities have taken action to restore the water quality in the St. Louis River Estuary, and to eventually
remove the eight remaining SLRAOC BUIs. This summary focuses on the research documenting water
quality changes over time associated with the excessive loading of sediment and nutrients BUI.
Executive Summary to the Beneficial Use Impairment Actions Associated with Investigations of Paleolimnology and Historic and Current Water Quality Condition in the St. Louis River Area of Concern
Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, 5013 Miller Trunk Hwy, Duluth, MN 55731. This report was produced by the Natural Resources Research Institute under contract to the Minnesota Pollution Control Agency and funded by the Minnesota Clean Water, Land and Legacy Amendment Clean Water Fund. The project was partially funded by the Minnesota Sea Grant College Program, NOAA, Department of Commerce under grant number NA14OAR4170080.
Reavie, Euan D; Alexson, Elizabeth; Axler, Richard P; Yost, Chad; Ladwig, Jammi; Nurse, Andrea; Estepp, Lisa; Krasutsky, Pavel A; Kennedy, Kathleen; Yemets, Sergiy; Engstrom, Daniel R.
Paleolimnology of the St. Louis River Estuary.
University of Minnesota Duluth.
Retrieved from the University of Minnesota Digital Conservancy,
Content distributed via the University of Minnesota's Digital Conservancy may be subject to additional license and use restrictions applied by the depositor.