Stormwater Program for Municipal Separate Storm Sewer Systems (MS4)
The municipal separate storm sewer systems (MS4s) stormwater program is designed to reduce the amount of sediment and pollution that enters surface and ground water from storm sewer systems. Public entities that own or operate an MS4 play a key role in preventing or reducing the negative impacts stormwater runoff has on our valuable water resources.
Proper stormwater runoff management in urbanized areas is especially important for restoring and protecting surface waters. Urbanized areas are more likely to have activities that contribute pollutants to stormwater runoff, like applying anti/deicing mixtures to roads; fueling vehicles; grease, oil, and other spills; landscaping; and using pesticides and fertilizers. Urbanized areas have a large amount of impervious surfaces, or surfaces that rain and snowmelt cannot pass through, such as streets, driveways, rooftops, parking lots and sidewalks. Stormwater runoff from these surfaces travels faster and in higher amounts, damaging rivers, streams, and wetlands; destroying aquatic habitats; increasing the amount of pollutants that enter surface waters; and limiting groundwater recharge.
Contents
MS4 stormwater program overview
MS4 stormwater permit
MS4 Permit Minimum Control Measure (MCM) overview and guidance
Guidance document to help local MS4 staff meet the requirements of the six MCMs in the MS4 General Permit and assist with overall stormwater management
- MCM 1 Public Education and Outreach
- MCM 2 Public Participation/Involvement
- MCM 3 Illicit Discharge Detection and Elimination
- MCM 4 Construction Site Stormwater Control
- MCM 5 Post-Construction Stormwater Management
- MCM 6 Pollution Prevention/Good Housekeeping
- General Stormwater Program Management
Other technical assistance and guidance
- MS4 fact sheets
- Visit the MPCA MS4 website for additional guidance documents and fact sheets
- Pollution prevention guidance
- Stormwater and Wetlands - Planning and Evaluation Guidelines
- Untreated Stormwater Runoff to Lakes, Streams, and Wetlands
- MS4 case studies
Total Maximum Daily Loads (TMDLs)
- TMDL Overview
- Summary of TMDL requirements in stormwater permits
- Forms and guidance for TMDLs
- TMDL Annual Report questions
- Summary of data received from permittees on MS4 TMDL permit reporting forms
- Visit the MPCA TMDL Project page for information on specific projects across the state
Other links
- MS4 staff contact information and staff assignments
- MS4 mapping tool is an electronic map tool using Geographic Information Systems (GIS) technology.
- Pond, lake, and wetland inventory