History of an Acronym – MS4

The Cuyahoga River in Cleveland burns in 1969 - image from patrickmurfin.blogspot.com.
The Cuyahoga River in Cleveland burns in 1969 – image from patrickmurfin.blogspot.com.

In July of 1969, Time Magazine ran a photo of the Cuyahoga River in Cleveland, Ohio completely and literally on fire. Truthfully, the photo was actually from a fire that had happened more than ten years earlier in 1952, not the fire that had just happened a month earlier. In fact, the river had caught on fire quite a few times and, up until then, not many people had cared. When the photo appeared in Time Magazine, however, Americans across the nation stared at the image and wondered incredulously how it could happen. How could we let our lakes and rivers grow so polluted that they literally caught on fire?

A sweep of updates to federal laws in 1972, commonly known as the Clean Water Act, set into motion decades worth of work since to nurse our nation’s polluted waterways back to good health and protect those that are still pristine from harm. The first step was to regulate industries dumping chemicals and other contaminants directly into lakes and rivers. Within 20 years, however, it became obvious that regulating these “point sources” alone would not be good enough.

In 1996, the US Environmental Protection Agency conducted a National Water Quality Inventory and came to the conclusion that stormwater runoff from cities was a leading source of water pollution. Not only do urbanized areas have more impervious surfaces like rooftops, parking lots and roads where rainwater can’t soak in, but also, they have stormwater infrastructure specially designed to quickly take rain and melting snow off roads to prevent localized flooding. In most communities built before the late 1970’s, storm pipes carry water from streets directly to nearby wetlands, lakes, streams and rivers. In Minneapolis and St. Paul, for example, most storm pipes connect to the Mississippi River. In Stillwater, some storm pipes travel to the St. Croix River, while others go to Lily, McKusick or Long Lakes. This stormwater carries with it a toxic combination of pesticides, fertilizers, oils, metals, pathogens, salt, sediment, litter and organic debris. Additionally, the water itself can be a problem during heavy rains and spring melt when the increased volume erodes ditches and streams, sending sediment downstream.

As a result of the water quality inventory, the Municipal Separate Storm Sewer System (MS4) general permit came into being. The program regulates cities and other entities that manage storm sewer systems and is administered in our state by the Minnesota Pollution Control Agency.

Most MS4s are cities, but watershed districts, counties, and townships can also be designated as MS4s, and some large campuses are regulated as well – places like universities, hospitals and prison complexes that operate their own private roads and drainage systems. Minneapolis and St. Paul, the two biggest cities in Minnesota, were the first to receive stormwater permits during Phase I of the program in 2000. Many smaller cities were added to the list during Phase II in 2005, and several more are added each year as the Twin Cities and other metro areas in Minnesota continue to grow. Currently, cities with more than 10,000 people that have storm sewer systems are automatically required to have a MS4 permit, but many smaller communities are regulated as well, either because they are within the larger Twin Cities metro area, or because their stormwater discharges to an “outstanding resources value water” such as the St. Croix River. In Washington County, MS4 entities include bigger cities like Cottage Grove, Woodbury, Lake Elmo, Stillwater and Forest Lake, as well as small cities like Dellwood and Willernie (near White Bear Lake), and even two mostly rural communities – Grant and West Lakeland Township.

MS4 entities are required to develop stormwater pollution prevention programs, educate the public about stormwater pollution, and engage citizens in solving local water pollution problems. The permit also requires MS4s to identify and stop illegal dumping (called illicit discharges), take steps to reduce runoff from construction and development, and practice “good housekeeping” to avoid polluting waterways during routine road and park maintenance. There are also separate permit programs to regulate industrial sites and construction sites.

In Washington County, MS4 entities collaborate with one another, as well as the county and watershed management organizations, to improve the efficiency and effectiveness of their stormwater pollution prevention efforts. One example is the East Metro Water Resource Education Program, created in 2006, which supports 22 local government partners and is hosted by the Washington Conservation District.

Learn more about stormwater permits and programs in Minnesota at: www.pca.state.mn.us/water/stormwater. Learn more about EMWREP at www.mnwcd.org/emwrep.