The MS4 (municipal separate storm sewer system) permit from the Minnesota Pollution Control Agency (MPCA) recently got an update. There are new stormwater system requirements that cities, counties, highway departments, and other organizations need to meet, and this comes with paperwork.
The overall purpose of the MS4 general permit is to protect water systems from the various pollutants that might wash into them through municipal stormwater systems. The MPCA did a five-year update of the document in November 2020, and the due date for applying for this updated permit is April 15, 2021. It’s a large document—28 pages with 174 questions—and can take a long time to fill out.
“A really important point: Whatever time you have planned for yourself and/or your staff to complete this form, plan on more time,” says Randy Neprash, a stormwater regulatory specialist with Stantec and the Minnesota Cities Stormwater Coalition (MCSC).
To help streamline the application process, Neprash hosted a how-to-apply webinar during the City Engineers Association of Minnesota annual meeting on January 29.
The permit, Neprash says, applies to stormwater systems owned by public entities that meet certain requirements in terms of population, urban classification, and proximity to impaired waters.
Some of these new items aim to more closely regulate pollutants such as chloride and bacteria. Others require municipalities to provide better documentation. For example, if a municipality claims to be meeting total maximum daily load regulations, it must now document its load reduction strategies and prove that they are MPCA-approved methods.
These new requirements, Neprash says, do not need to be met immediately. Once the MS4 general permit is approved by the MPCA, municipalities have 12 months to update their stormwater pollution prevention plans, revise or add to city ordinances, and update best management practices.
Overall, Neprash says, municipalities with well-documented stormwater programs will have a quicker time with the application process. It helps to already meet the requirements of the 2013 MS4 permit and to have storm sewer system maps.
The MPCA website offers a variety of resources for permittees to use when applying for the permit. This includes an MS4 toolkit and an MS4 digital document library.
The MCSC also offers resources, meetings, and advice to its members. Neprash recommends contacting him with questions at [email protected] for more information.
—Sophie Koch, LTAP freelancer