City Projects

Storm Water Division Duties

As appropriate we coordinate with other agencies and citizens to:

  • Educate the public on storm water pollution prevention;
  • Screen, sample, and test storm water for illicit discharges and pollution levels;
  • Report test results and other required activities to the Montana Department of Environmental Quality;
  • Coordinate response to storm water flooding situations; 
  • Construct, upgrade, and maintain storm water facilities (to view Missoula's Storm Water infrastructure and facilities, go to the storm water web map and select the "Storm" Layer); and
  • To see a detailed view of all storm water division duties review the Storm Water Facility and Operations Plan.

Image showing part of the Missoula Storm Water Map, including hundreds of drywells in a square mile area, with a link to the full page map.

Working Together

For the past 10 years, the City has collaborated with the Missoula Valley Water Quality District to enforce water quality laws, monitor groundwater cleanup sites, oversee household hazardous waste collection, and more. The community’s unique Missoula Water Quality Ordinance provides strong protection of Missoula's waterway through the regulation of discharges, such as dry cleaner solvents, as well as the use of street deicers. Enforcement and co-permit responsibilities are a partnership as defined by the 2003 Interlocal Agreement. This partnership continues following the creation of the Storm Water Division because both entities have similar goals but different tasks.

The Storm Water Utility Division also works with educational partners such as Montana Natural History Center and the Watershed Education Network. We are working together to cultivate and develop our future generations as stewards of Missoula's greatest treasures, our water.

Image showing bright green liquid pooling over the curb and crosswalk in a Missoula Residential NeigMajor Water Quality Accomplishments

  • Extension of the sewer system in older areas of the community previously served by outdated cesspools and seepage pits;
  • Adoption of the first municipal phosphate ban in the Clark Fork River watershed, leading the way for other communities;
  • Storm water and flood control improvements for the Pattee Canyon, South Hills, 39th Street, and Miller Creek areas;
  • Installation of treatment devices for storm water discharges in downtown Missoula at Orange Street and Silver Park and planning for improved treatment at Caras Park and Buckhouse Bridge; and
  • Installation of the hybrid poplar project, 90,000 trees planted near the treatment plant and watered with effluent that would have gone to the Clark Fork River, eliminating significant amounts of nitrogen and phosphorous.

Meeting State and Federal Regulations

The Storm Water Discharge General Permit MS4 is managed by Montana DEQ to help ensure water quality, with each major municipality participating. Missoula's MS4 five year permit, effective January 1, 2017 - December 31, 2021 requires the City to have a full-time storm water coordinator, increase hands-on education about storm water pollution and prevention, as well as increase public participation.

The 2017 Annual Report reviews the City of Missoula’s Storm Water Division’s activities for the 2017 MS4 permit year. For a broader look at planned activities see Missoula’s Storm Water Management Program (SWMP). This details local pollutants of concern, their reduction, and mitigation in the City of Missoula. Activities described are in accordance with requirements stated in the MT state General MS4 permit. Provide your comments in this online form or by contacting the Storm Water Division.

Beyond this MS4 General Permit the City of Missoula is meeting regulations to comply with the U.S. Clean Water Act and the Montana Pollutant Discharge Elimination System (MPDES).

If you have construction project complaints or suspect illicit discharge, report online anonymously. To reach the general spill hotline during business hours call 406-258-4890, or, for after hours dispatch call 911.