Upper Mississippi River TSS TMDL report
Located in the north central region of Minnesota, the Mississippi River - Grand Rapids Watershed drains more than 1.3 million acres of land from the Laurentian Continental divide to the Mississippi River near the city of Palisade. It crosses through the counties of Aitkin, Cass, Carlton, Itasca, and St. Louis and sustains many valuable resources throughout its expanse. It is home to the communities of Grand Rapids (pop. 10,866), McGregor (390), and Remer (370), among many others.
The watershed maintains around 2,000 miles of streams and rivers and 625 lakes larger than 10 acres. Of these lakes, 79 produce wild rice, a unique resource that Minnesota produces more of than any other state, and 48 are cold water fisheries, beneficial to supporting healthy trout populations in the watershed. These beautiful lakes make the watershed an attractive destination for recreation. Forest land makes up most of the watershed (56%), providing many excellent ecosystem services such as water filtration and habitat for diverse species.
What's being done
Surface Water Assessment Grants completed sampling on 147 lakes within Itasca County. The Big Sandy and Lake Minnewawa TMDL project has been completed and approved by EPA. Intensive water quality monitoring began in this watershed in 2015.
Lakes and streams with enough data were assessed against state standards in 2017. Only six of the 73 assessed streams were found to have high levels of bacteria, but 17 streams do not meet standards for aquatic life (fish and/or bugs). The stressors to aquatic life (fish and bugs) in the watershed are largely due to historical ditching, which causes streams to experience low dissolved oxygen, increased erosion, and degradation of habitat by sedimentation. The most likely causes of bacteria impairments in the Mississippi River – Grand Rapids Watershed are wildlife and livestock encroachment and failing septic systems.
216 lakes in the watershed had at least some data collected and were reviewed for impairments. Of these lakes, 117 had enough water quality information to conduct a formal assessment of aquatic recreation (whether they are swimmable and fishable), and only 11 do not meet standards. Fish populations were assessed in 49 lakes and one of those lakes did not meet the expected standards.
Strategies for addressing the identified issues include promoting shoreland protection and programs for forest protection, management of lake levels, in-lake plant and fish communities, and/or sediment phosphorus release, restoring altered stream hydrology, and performing ditch restorations (primarily in peatlands, due to the substantial ditching which has occurred there).
- Mississippi River - Grand Rapids Watershed WRAPS Report (wq-ws4-61a) (MPCA approval 9/18/2019)
- Summary: Mississippi River - Grand Rapids Watershed WRAPS report (wq-ws4-61b)
- Mississippi River - Grand Rapids Watershed TMDL Report (wq-iw8-58e) (EPA approval 10/1/2019)
- Mississippi River - Grand Rapids Watershed TMDL: EPA approval letter (wq-iw8-58g)
- Our Upper Mississippi River Large River and Basin Restoration and Protection Strategies (wq-ws4-38b)
Monitoring and assessment reports and data
- Mississippi River - Grand Rapids HSPF Model Recalibration (wq-iw8-58n)
- Hydrologic and Water Quality Calibration (wq-ws1-18)
- Mississippi River - Grand Rapids Watershed Monitoring and Assessment Report (wq-ws3-07010103b)
- Mississippi River - Grand Rapids Watershed Stressor Identification Report (wq-ws5-07010103a)