Boring bureaucracy keeps the water clean

On November 16, the Minnesota Pollution Control Agency (MPCA) will issue a new five-year MS4 General Permit to guide stormwater management in nearly 300 communities around the state. It’s one of those boring government programs that never quite makes headline news but quietly benefits millions of Minnesotans that enjoy fishing, swimming, boating, and drinking clean water.

The MS4 Program helps to protect urban lakes like Forest Lake from stormwater pollution.

To understand the significance of the Municipal Separate Storm Sewer System (MS4) permit program, it helps to take a step back in time to the 1940s, 50s and 60s when the Mississippi River in Minneapolis-St. Paul was nearly void of life and the Cuyahoga in Cleveland caught fire more than a dozen times.

The Clean Water Act of 1972 established a structure for the U.S. Environmental Protection Agency (EPA) and state agencies to regulate water pollution and set water quality standards for rivers, lakes and streams around the country. The first step was to address industrial pollution from factories and pipes. Soon, however, it became obvious that industrial regulation alone wouldn’t be enough to ensure clean water in urban areas.

Despite regulations designed to reduce industrial water pollution, litter and other contaminants still flow into lakes and rivers from city stormwater pipes.

In developed communities, storm sewers drain rain and melting snow off of roads and into stormwater pipes to prevent flooding. If built before the late 1970’s, these stormwater pipes usually carry runoff directly to nearby wetlands, lakes, streams and rivers without treatment. As a result, pesticides, fertilizers, oils, metals, bacteria, salt, sediment, litter and other debris from parking lots, roads, and yards flow into and pollute our water.  

The U.S. EPA created the MS4 Program in 1990 to address the growing threat of stormwater pollution. In Minnesota, the program is administered by the MPCA and applies to roughly 300 cities, townships, counties, watershed districts, and large campuses such as universities, hospitals and prison complexes that operate their own private roads and stormwater drainage systems. This includes more than 20 permit holders in Washington County.

When it rains, stormwater pipes drain water from roads and parking lots and send it into nearby rivers and lakes. In communities developed before the late 1970s, these pipes usually go directly to the water without entering a stormwater pond or other treatment first.

MS4 permittees are required to develop stormwater pollution prevention programs, educate the public about stormwater pollution, and engage citizens in solving local water pollution problems. The six categories of required action, known as minimum control measures, include:

  1. Public education and outreach;
  2. Public Participation and Involvement;
  3. Illicit Discharge Detection and Elimination (illegal dumping into storm sewers and ditches);
  4. Construction Site Stormwater Runoff Control;
  5. Post Construction Stormwater Management; and
  6. Pollution Prevention and Good Housekeeping [in municipal operations such as parks maintenance and public works].

In addition, there are separate permit programs to regulate water pollution from industrial sites and construction sites. The MS4 Permit Program does not address issues such as flooding or aquatic invasive species that are not related to stormwater pollution. Likewise, it does not apply to agricultural or rural water pollution outside of permitted communities.

The new Minnesota MS4 General Permit has an extra focus on road salt and its impacts to water quality.

Though you’ve probably never heard of the MS4 Permit Program, you may be familiar with local pollution prevention efforts the permit has inspired. Storm drain stenciling, Adopt-a-Drain, community clean-up events, household hazardous waste collection days, volunteer water quality monitoring, and rain garden workshops are just some of the many local-led programs designed, in part, to reduce stormwater pollution and meet MS4 permit requirements. The permit also addresses concerns such as winter salt storage, construction site erosion and sediment control, and runoff from new development.

To learn more about the MS4 Program, visit

You can also visit your city’s website to learn more about local stormater pollution prevention efforts.