Pollution in the Mystic

Cuyahoga River, Ohio, 1968. Oil on the surface ignited on more than one occasion.     Photo credit: Cleveland State University Library

Cuyahoga River, Ohio, 1968. Oil on the surface ignited on more than one occasion.

Photo credit: Cleveland State University Library

The good news is that, thanks to the Clean Water Act, pollution no longer looks like a burning river.

The Mystic River–like many urban rivers around the country–is cleaner today than it has ever been.  The Clean Water Act has been a major environmental success story. But our work is not yet done. As the most urbanized watershed in New England, the Mystic River watershed is especially subject to stormwater pollution—now one of the leading sources of pollution in our water today.

What is Stormwater Pollution?

“Stormwater” is a fancy word for rain or snowmelt. “Stormwater runoff” occurs when rain flows over land–driveways, lawn and streets–into the nearest storm drains and catch basins and then discharges directly into our water bodies through pipes in the network of stormwater pipes–WITHOUT being treated.

Stormwater pollution happens when the water picks up pollutants such as car oil, dog waste, excess fertilizer, herbicides, and pesticides on lawns, salt and de-icing materials, cigarette butts, and other trash. These pollutants go down the nearest catch basin and end up in our lakes, rivers and streams.

In addition to polluting the water, stormwater can cause flooding, sewage backups, and erosion. As more and more open space land is developed and covered by impervious surfaces (surfaces where water cannot penetrate), stormwater cannot infiltrate into the ground and is forced to become runoff.

Finally, urban stormwater systems all over the country are commonly contaminated by the wastewater sanitary sewer system, through a variety of mechanisms.  So human bacteria and other pathogens that are a threat to public health are introduced to rivers and streams through the stormwater system.  Reducing bacteria inputs is a major goal of sampling, regulation, and infrastructure investment.

How polluted is the Mystic River?

Parts of the Mystic watershed–including the Mystic River itself— are cleaner than you might think (see green segments) while there is still work to be done! The map shows water quality grades based on bacteria counts from the sampling sites shown.  Each water body gets a grade based on an average of values from all sites in the water body from the past three years.  Click on sampling points for more information about the data behind the map.

MyRWA, with the help of a dedicated corps of volunteers, has been collecting water quality data for 18 years now. Based on this data, along with data from the Massachusetts Water Resources Authority (MWRA), a report card is put together every year by the United States Environmental Protection Agency (EPA). Water quality grades are given to sections of the rivers and streams based on how often they comply with state swimming and boating standards.  

The federal government, the state, municipalities, and organizations like ours work together to see that the Clean Water Act is enforced. The historic cleanup of Boston Harbor—of which the clean up of the Mystic River is a part— is a national environmental success story of which we should all be proud.  There is still work to be done.

So what exactly is polluting our water?

Explore the links below to learn more about these main groups of contaminants:

What can be done?

Cities and towns work to limit the amount of pollutants that make their way into water bodies. Through MyRWA’s Stormwater Collaborative municipalities share resources and ideas to reduce stormwater pollution. Other actions they take include:

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

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

  3. 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 in so-called Illicit Discharge Detection and Eliminiation (IDDE), to find and eliminate sources of wastewater intrusions into the stormwater system.   

What can you do?

There is LOTS you can do! Check out our Clean Water Tips:

  1. You hate stepping in it. And fish hate swimming in it, too! Regularly scoop your dog's poop from public areas AND your back yard, before it washes into our waterways.

  2. Test your soil and read the label before you apply fertilizer. If you use too much fertilizer, the excess will just wash away in the next rain, polluting your local waterways.

  3. Capture the rain that falls on your property in a rain barrel, rain garden, or on the leaves of your trees and shrubs. You’ll reduce flooding and keep our waterways clean.

  4. After enjoying the fall foliage, bag your leaves for curbside pickup, or mulch them. But whatever you do, don't dump them in a storm drain or leave them on the sidewalk!

  5. When the snow melts where do you think all the salt and de-icer goes? You got it! It flows into our catch basins and straight into our waterways. Keep those chemicals out of our water - shovel first, use de-icer instead of salt, and use de-icer sparingly!