Every two years, the Minnesota Pollution Control Agency (MPCA) creates an updated list of impaired waters in accordance with the federal Clean Water Act.1 The MPCA proposes the addition of 305 water bodies — including 417 new impairments — for its updated 2022 impaired waters list.2 Of special significance are the Greater Minnesota waters now designated as having perfluorinated alkylated substances contamination.3 The most prevalent impairment continues to be fish impairments, with bacteria, sediment, and nutrients also contributing to the depreciation of Minnesota’s water resources.4
The expansive new list of impaired waters also presents potential impacts to new construction projects in Minnesota. For construction projects with discharge points within one aerial mile of, and flowing to, water bodies with construction-related impairments (i.e., nutrient eutrophication biological indicators, turbidity, total suspended solids, dissolved oxygen, fish bioassessment, aquatic plant bioassessment, and aquatic macroinvertebrate bioassessment), additional best management practices (BMPs) are required under Minnesota Construction Stormwater General Permit MNR100001.5 As a result, qualifying projects may experience delays in permit application reviews and approvals, tighter soil stabilization timeframes, and more onerous BMP requirements:
- Projects or common plans of development or sale that disturb fifty acres or more that discharge stormwater within one mile of impaired waters are required to submit a Stormwater Pollution Prevention Plan to the MPCA subject to a 30-day review period;
- Areas of exposed soils in which construction activity has temporarily or permanently ceased for a period of seven calendar days — rather than fourteen calendar days for non-impaired receiving waters — must be stabilized immediately;
- Temporary sediment basins must be installed for areas of five acres or more — rather than ten acres for non-impaired receiving waters — disturbed at one time and draining to a common point; and
- Projects may be subject to Total Maximum Daily Load or Waste Load Allocation requirements as determined by the MPCA.6
Minnesotans are welcome to submit comments on the addition or removal of impaired waters to the 2022 draft impaired waters list during the public notice period through Jan. 7, 2022.7 The draft 2022 impaired waters list is due to the federal Environmental Protection Agency by April 1, 2022.8
1Minnesota’s Impaired Waters List, Minn. Pollution Control Agency, (last visited Jan. 4, 2022).
2Cathy Malakowsky, Minnesota adds 305 streams and lakes to its impaired waters list, including new PFAS waters in Greater Minnesota, Minn. Pollution Control Agency, (Nov. 8, 2021).
5Minn. R. 7090.2010 (2007); See also MNR100001 §§ 23.1- 23.14 (2018).
7Malakowsky, supra note 2.