Neponset River Report Card: 2020

The U.S. Environmental Protection Agency (EPA) has issued a water quality report card for the Neponset River and the bacteria “grades” can be seen in the map below.

The report card shows the result of water samples taken from various locations across the 120-square mile Neponset River Watershed and is made possible through NepRWA’s Community Water Monitoring Network (CWMN).

The majority of water bodies in the Watershed get a bacteria grade from A+ to B-.

What’s in a Grade?

There are multiple factors that affect water quality and the bacteria “grade” of the Neponset River:

Stormwater runoff, which occurs during rain events and washes contaminants such as dog waste into streams and ponds via storm drain systems.
Leaking sewer pipes or sanitary sewer overflows, which allow raw sewage to flow into streams and ponds.
Poorly maintained septic systems, which allow bacteria and chemicals to flow from groundwater into streams and ponds.