Legislation passed in 2019 and amended in 2021 changed the regulated area for certain MS4s.
The following legislation took effect August 1, 2019.
Sec. 109. APPLYING STORM WATER RULES TO TOWNSHIPS. Until the Pollution Control Agency amends rules for storm water, Minnesota Rules, part 7090.1010, subpart 1, item B, subitem (1), applies only to the portions of a city, a town, and unorganized areas of counties that are designated as urbanized under Code of Federal Regulations, title 40, section 122.26(2)(9)(i)(A), and other platted areas within that jurisdiction.
Prior to this legislation, cities and townships exclusively regulated under Minn. R. 7090.1010, subp. 1(B)(1)1, were required to manage stormwater in compliance with the general permit for small MS4s in the “entire” jurisdiction. The 2019 legislation reduces the land area in which stormwater must be managed within the permittees’ jurisdiction to only the Urbanized Area (UA), as defined by the most recent decennial census, and other “platted areas” as defined by Minnesota Statute 462.352, subd. 1322.
Changes in regulated area for 38 MS4s (see following list) due to this legislation generates uncertainty about the degree of applicability for previously assigned US Environmental Protection Agency (EPA) approved wasteload allocations (WLAs). For example, if a Total Maximum Daily Load (TMDL) study area includes a portion of a city or township that has no urbanized or platted areas, that EPA approved WLA may not be applicable to the permittee this permit term. As the MPCA increasingly gains access to “platted area” data, and 2020 decennial census data (expected to be released by the U.S. Census Bureau fall of 2022), the MPCA intends to work with affected MS4s to better determine assigned WLA applicability.
1 Any MS4s partially in urbanized area with populations up to 4,999 or between 5,000-9,999 not discharging to a special water.
2 Minn. Stat. 462.352, subd. 13: "Plat" means the drawing or map of a subdivision prepared for filing of record pursuant to chapter 505 and containing all elements and requirements set forth in applicable local regulations adopted pursuant to section 462.358 and chapter 505.
|Carver City MS4||Brockway Township MS4|
|Dayton City MS4||Cascade Township MS4|
|Dellwood City MS4||Duluth Township MS4|
|Dilworth City MS4||Empire Township MS4|
|Eagle Lake City MS4||Jackson Township MS4|
|Grant City MS4||Laketown Township MS4|
|Hanover City MS4||Le Sauk Township MS4|
|La Crescent City MS4||Louisville Township MS4|
|Long Lake City MS4||Mankato Township MS4|
|Medina City MS4||Marion Township MS4|
|Newport City MS4||Midway Township MS4|
|North Oaks City MS4||Minden Township MS4|
|Nowthen City MS4||Rochester Township MS4|
|Proctor City MS4||Sauk Rapids Township MS4|
|Rice Lake City MS4||South Bend Township MS4|
|Saint Augusta City MS4||Spring Lake Township MS4|
|Skyline City MS4||St. Joseph Township MS4|
|St. Bonifacius City MS4||Watab Township MS4|
|Wayzata City MS4||West Lakeland Township MS4|
The affected MS4s should be proactive in working with their county to determine what their platted area is. Once the 2020 Census results are available, MPCA staff will begin reaching out to MS4s to help determine wasteload applicability.