Stormwater

Stormwater is rainwater and snowmelt that collects on the ground as a result of rain and snowfall. When this water flows across the surface of the ground it picks up soil and pollutants and carries them to the nearest stream, river, or lake. Stormwater is NOT TREATED at the treatment plant.

Impervious surfaces are materials that do not allow water to infiltrate into the ground. Asphalt parking lots and streets, concrete sidewalks, rooftops, and compacted gravel areas are examples of impervious surfaces. Impervious surfaces create runoff that must be captured and carried by Duluth's storm sewer system.

Duluth's stormwater utility system consists of over 400 miles of pipe, over 100 miles of ditches, and about 3,000 culverts. Storm drains and catch basins carry stormwater from the streets and parking lots to the nearest waterway. Catch basins are the heavy steel grates located along the curbs, usually near intersections. There are nearly 11,000 catch basins in the City of Duluth.

The City of Duluth has forty-four named streams within its boundaries, and sixteen of these are designated trout streams. Duluth's streams play an important role in conveying stormwater from the land to the St. Louis River and Lake Superior. They are a natural stormwater system that makes up the community drainage system. City staff works to maintain the streams by clearing brush from inlets and outlets of culverts, removing sediment from storm sewer pipes that lead to the streams, plus working to reduce erosion.

Protecting Duluth's stormwater can be easy. Think of your curb and gutter as lakeshore property- remember that whatever is on the street washes down the storm drains and flows straight into our streams, then to the St. Louis River and Lake Superior. Don't blow your leaves and grass clippings into the street. Sweep up road sand in the spring. Pick up pet droppings. Wash your car on the lawn where the soapy water can soak into the ground, not the driveway where the water will flow into the storm sewer. Don't litter- much of that trash ends up in our lakes and streams. Reduce soil erosion- sediments are usually fine-grained sands, silts, and clays that can cover up coarser sediments and the spaces between rocks and cobbles that provide habitat for aquatic life and suffocate fish eggs. Learn more about them at the Lake Superior Streams website.

Maintaining this system is no easy task. Utility Operations uses hydraulic rodders and high-pressure jetters to flush and clean the storm sewer pipes, along with a small closed-circuit television camera mounted on a tracked crawler to drive down the pipes and inspect for cracks, breaks, leaks and pollution sources. If breaks are detected in the system, Duluth's stormwater construction crew makes the repair. Utility Operations staff includes a team of Utility Resources Specialists who are dedicated to preserving the high quality of water in our area. Their job covers a wide range of duties: erosion control, flow monitoring, Inflow/Infiltration into sanitary sewers, illegal connections, illicit discharges, sump pumps, bypass valves, sedimentation measurement, school presentations, homeowner meetings, and much more. The stormwater utility also has staff in Engineering.

The City of Duluth’s stormwater utility partners with many organizations, both private groups and governmental agencies. Collaborating with others allows us to share resources and save money. By bringing everyone together, a consistent message is created to avoid confusion. Having a wide variety of agencies working together also allows us to share expertise in our specialized areas.

The Regional Stormwater Protection Team (RSPT) was formed in 2002 by 26 regional communities & agencies who came together to provide mutual support, education and outreach regarding protection of their shared Western Lake Superior Watershed. The all-volunteer organization has pooled resources and successfully attracted funding from several granting agencies, which has allowed implementation of a multi-year media campaign, 2005 and 2007 Watershed Festivals, representation at regional events, home shows, and development of numerous presentations and publications. Many member organizations have been recognized as leaders in their protection of water resources, receiving regional, state and national recognition.

The Duluth Urban Watershed Advisory Committee (DUWAC) initially met in 2015 and continues today as a Voluntary Cooperation Organization that encourages management of local streams on a watershed basis. An initial action of the committee was to create a vision statement to help guide the group, which is “Our water resources and associated ecosystems become healthier and more resilient through public engagement and local government collaboration.” This statement will assist in community involvement helping to develop priorities for cooperative watershed management. To formalize the structure of the committee, a memorandum of understanding (MOU) was created and adopted by all member communities in 2018. One of the goals of the Duluth Urban Watershed Advisory Committee is to identify and prioritize projects within and between communities, maximizing efficiency to ensure that communities are getting the biggest impact from their investments. Other benefits of DUWAC are to improve our community’s understanding and knowledge about water resources and to help identify options to update local codes and ordinances that will improve water resources within our watersheds. A secondary goal of the committee is to recognize efficiencies and opportunities to share expertise between its members.

RESIDENTIAL: Stormwater fees are calculated based on the number of Equivalent Residential Units (ERUs) on a property. One ERU equals 1,708 square feet of impervious surface. 1,708 square feet is the average impervious surface area in Duluth for a single family home. All residential buildings are billed 1 ERU per living unit.

COMMERCIAL/INDUSTRIAL: Commercial/Industrial properties are billed based on the total square footage of impervious surface on the property (typically buildings and parking lots). The total impervious square footage of a commercial property is then converted to ERUs. For example, a medium-sized business might have a total impervious surface of 11,000 square feet. 11,000 sq. feet/1,708 sq. feet per ERU = 6.4 ERUs.

Stormwater Rates

Credits for installing engineered Best Management Practices (BMPs) are available for non-residential properties. Most properties that install stormwater BMPs receive a reduction of 37.16% for the area of the property that flows to the BMP.

In order to receive credit, the BMP must (at a minimum):

  1. Be designed (and signed) by a licensed, professional engineer.
  2. Be sized to capture at least the first 0.5” of runoff.
  3. Have annual, documented inspections by the property owner, licensed professional engineer, or other qualified individual.
  4. Be maintained as needed based on the annual inspections.

Additional water quality benefits including temperature reduction, habitat creation, and runoff rate control are preferred, if possible.

The best thing you can do to reduce your stormwater fee is to reduce your impervious surface. Vegetating gravel areas, removing excess concrete and blacktop parking areas, and even removing vacant buildings can all quickly reduce your stormwater fees. Note: The City of Duluth recommends contacting the Stormwater Utility Programs Coordinator 218-730-4130 (or submit the billing request form) before proceeding with efforts to reduce your stormwater fee as the property may already be receiving credit.

If you feel that your property is being billed incorrectly, or if you would like more information on what your stormwater fee includes, please fill out and submit the form below. Engineered stormwater Best Management Practices (BMPs) can be installed to reduce stormwater fees on non-residential properties.  If you have copies of these plans, please mention this in the comments below.

Stormwater Fee Review Form

Contacts

If you have any questions or concerns about stormwater, or if you would like to review and comment on the City of Duluth's Stormwater Pollution Prevention Plan (SWPPP), please contact the Engineering office at 218-730-5200.

To report stormwater utility issues, please call the Utility Operations office at 218-730-4130.