Permits & Regulations


The City of Billings is a Municipal Separate Storm Sewer System (MS4) co-permittee with Montana Department of Transportation. The City also has a MS4 partnership with Yellowstone County. The MS4 General Permit requires permittees to develop, implement, and enforce a Stormwater Management Program (SWMP). The SWMP shall be designed to reduce the discharge of pollutants from the permitted MS4 to the Maximum Extent Practicable (MEP), to protect water quality, and satisfy the appropriate water quality requirements of the Montana Water Quality Act. The SWMP must include Best Management Practices (BMPs). The SWMP is available and open to public comments by email.

The City of Billings Stormwater Program consists of BMPs from the following categories: