Stormwater Collaborative — Mystic River Watershed Association

What is stormater pollution?

Stormwater pollution occurs when rain or snowmelt washes pollutants such as oil, fertilizers, pet waste and trash over land and into the nearest catch basin, which flows directly to the nearest water body. The US Environmental Protection Agency estimates that contaminants in stormwater runoff causes over half of the pollution in our waterways.

The Problem

Our cities are among the oldest in the United States and have aging stormwater infrastructure. During heavy rainfall, these systems can become overwhelmed, occasionally resulting in the mixing of sewage with our rivers.

As our cities developed, we replaced natural land with surfaces like streets and sidewalks, preventing rain absorption. Consequently, rainwater, along with debris and pollutants like leaves and fertilizers, flows into our drains.

As an urban watershed, managing trash is a daily challenge. The litter visible in our rivers is not directly thrown by individuals but is gathered from streets, sidewalks, and parking lots during rain events.


You can make a difference!

CHEck out these clean water tips to Protect waterWAYS, wildlife, pollinators, and YOU

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Our communities can make a difference

Green infrastructure and improved policies can help stop pollutants from going into the Mystic

Curious about what a stormwater wetland and open space might look like? This is a photo of the Maillet, Sommes & Morgan Conservation Land in Reading. Credit: Isaiah Johnson

Cities and towns work to limit the amount of pollutants that make their way into water bodies. Some common practices include:

  1. Green Infrastructure—such as rain gardens, constructed wetlands, or infiltration trenches can help filter out pollutants before they reach the Mystic. Interested in learning more about on-the-ground green infrastructure projects in the watershed? Read here about our ongoing green infrastructure projects. Learn more about constructed wetlands in Everett, Reading, Stoneham, and Woburn.

  2. Street sweeping — picking up pollutants before they go down the catch basin and into our waterways.

  3. Labeling catch basins, reminding residents that whatever goes down our catch basins flows directly into our water.

  4. Separating sewer and stormwater lines. Ever notice a construction project that digs up the street and seems to go on forever? It’s possible that your city or town is making improvements to either separate sewer lines and stormwater pipes, or updating old infrastructure so that sewage cannot seep into stormwater pipes.

Municipalities also spend a significant amount of money on so-called Illicit Discharge Detection and Eliminiation (IDDE) to find and eliminate sources of wastewater intrusions into the stormwater system.  


stormwater Collaborative

The Mystic River Watershed Association (MyRWA) has convened the Mystic River Stormwater Collaborative, a group of 15 towns and cities in the watershed dedicated to the common goal of reducing stormwater pollution, the primary source of water pollution today.

As is required by the Environmental Protection Agency, municipalities are working to reduce the amount of pollutants that enter our water. One way they do this is through educating residents, businesses, developers and industry leaders in their communities on how we all can reduce stormwater pollution. MyRWA supports these efforts by creating monthly educational materials for the municipalities to disseminate.

The materials we create — social media posts, videos, brochures, flyers, press releases and educational curriculum — aim to raise public awareness about stormwater pollution and inspire stewardship.

Participating municipalities