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Municipal Storm Water Program
Municipal Storm Water Program
The goal of the Municipal Separate Storm Sewer System (MS4) program is to reduce the discharge of pollutants to surface waters of the State. An MS4 is a system of drainage (including roads, storm drains, pipes, and ditches, etc.) that is not a combined sewer or part of a sewage treatment plant. During wet weather, pollutants are transported through MS4s to local water bodies.
Storm water discharges from a regulated MS4 to a surface water of the State in an urbanized area are subject to regulation under the National Pollutant Discharge Elimination System. MS4 permittees generally include the following municipal entities: cities, townships, villages, county agencies, universities, and school districts. The Department completed maps to identify MS4s located in an urbanized area that may require coverage under an MS4 permit.
Who may be regulated: Urbanized Area Maps
How to view permits on public notice: MiEnviro Public Notice
The following documents are available to assist with completing the abbreviated MS4 application form for permit reissuance in the MiEnviro Portal.
- Total Maximum Daily Loads Applicable to FY24 MS4 Permittees
- Total Maximum Daily Loads Applicable to FY23 MS4 Permittees
- Creating KML Files for MS4 Outfalls and Points of Discharge
Compliance Assistance Documents
The following documents are available to assist with developing and implementing a Storm Water Management Program (SWMP) as part of the MS4 program.
- Maintenance of Common Storm Water Best Management Practices
- Public Education Program (PEP) Guidance
- MS4 Progress Report MiEnviro Instructions (pptx)
- Post-Construction Storm Water Runoff Controls Programs
- Illicit Discharge Elimination Program Compliance Assistance Document
- Potential Adverse Impacts of Alternative Deicers
- Wastewater Discharge from Mobile Power Washing
- MS4 Catch Basin/Street Sweeping BMP
- Catch Basin Materials Management Guide
- Vehicle and Equipment Washing
- Dry-Weather Screening: A Guide for Permittees
- E. coli Total Maximum Daily Loads for MS4s in Impaired Watersheds
- Municipal Separate Storm Sewer System (MS4) Program Calculator (xlsx)
- Municipal Separate Storm Sewer System (MS4) Program Calculator Manual
- EPA's National Storm Water Calculator
- EPA's Stormwater Capture and Use (SCU) Infographics
- EGLE Best Management Practices Manual (Updated)
- Low Impact Development Manual for Michigan
- Information and Education Publications, Including Be Storm Water Savvy
- Part 5 Rules - Spillage of Oil and Polluting Materials
- National Menu of Storm Water Best Management Practices
- Storm Water Management Ordinances
- NOAA Atlas 14 Precipitation Frequency Estimates
- 90-Percent Annual Non-Exceedance Storms
- EPA's Stormwater Smart Outreach Tools