Stormwater Pollution

Through grants and partnerships with local communities, we are working to reduce polluted stormwater runoff throughout the watershed. 


When rain falls on hard surfaces it washes a number of pollutants into storm drains including:

  • bacteria and parasites from pet waste
  • chemicals from fertilizer, pesticides, herbicides
  • Phosphorous from leaves and grass clippings
  • snow/ice melt chemicals and sand
  • motor oil, antifreeze, and transmission fluid
  • all types of litter

Storm drains are connected via underground pipes to nearby water bodies, and all of the contaminated runoff flows directly into local streams, rivers, ponds, and the ocean, untreated.

Polluted stormwater causes problems for local drinking water sources; recreational activities like swimming, boating and fishing; and aquatic life.

The simplest way to prevent stormwater pollution is to keep our pavement clean and redirect water away from storm drains


NepRWA Helps Communities thru Partnerships

On July 1, 2018, the Environmental Protection Agency finalized a tough new stormwater permit for local municipalities.

We plan to help our communities with their stormwater cleanup efforts through regional cooperation and resource sharing, under the umbrella of the Neponset Stormwater Partnership (NSP).

The partnership communities are cooperating on creating key permit documents, printing regional public outreach materials, creating model stormwater bylaws, and figuring out the best way to pay for it all. The goal is more effective cleanup at a lower cost, through economies of scale.

Partners include the towns of Canton, Dedham, Foxborough, Medfield, Milton, Norwood, Quincy, Sharon, Stoughton, and Westwood, along with the Metropolitan Area Planning Council (MAPC), and the Neponset River Watershed Association.

Learn more about the Neponset Stormwater Partnership:


Additional Projects Include:

With few exceptions, most Neponset Watershed stormwater enters the river untreated – a major contributor to Neponset River’s failure to meet fishable/swimmable water quality standards during wet weather.

Over the past few years, NepRWA has been working with towns to find the best places to install structural stormwater Best Management Practices (“BMPs”) to help to treat stormwater and clean it before it discharges to the river.


Best Management Practices (BMPs)

Before the landscape was developed, far more rainwater would seep into the ground and be filtered by soil, plant roots and microorganisms, before joining the groundwater or seeping from the soil into a waterway.

Today, realizing just how much of the ground has been covered in impervious material, communities are incorporating stormwater-cleaning structures, called BMPs  into the built landscape.  Examples of BMPs include bioretention cells, rain gardens and tree-filter-boxes.

Learn more about stormwater BMPs.


Click here to learn how to reduce polluted stormwater runoff on your property.