NepRWA’s Hotspot Program allows us to follow up on problem areas identified through our Community Water Monitoring Network (CWMN) Program.

Staff visit problem sites and collect numerous samples to zero in on specific sources of pollution, such as sewer leaks and other illicit discharges. Once a problem is isolated, we work with local communities to get it fixed.

Common pollution sources in the Neponset Watershed are:

  • sewer leaks
  • illegal dumping into storm drains or along stream banks
  • illegal connections between the house’s sewer line and the storm drain system
  • aging infrastructure and poor behavior

The Hotspot Program was started by a group of generous individual donors in 2015. We typically sample more than 50 outfalls a year and uncover 1-2 pollution hotspot sources a year.

Pollution sources can be difficult to uncover. However, the water quality problems found in a waterbody can give us clues about potential sources. Those clues guide where in the hot spot stream we investigate and what tests we use.

Please email NepRWA River Restoration Director, Sean McCanty at if you have any questions about the Hotspot Program. 

View Hotspots on our interactive map, below.

Hotspot Sampling Map

In the upper left corner of the Hotspot map, you will see icons that provide features such as a legend, among others.

  • Clicking on the legend will show you three different symbol shapes:
  • The circle symbols represent testing that was done on water discharging from outfalls.
  • The square symbols are for samples taken directly from a stream.
  • The diamond symbols are places where we measured dissolved oxygen.
  • The color-coding from green to red indicates areas where the data has come back as clean, suspicious, or problematic.
  • Right below the icons are buttons to zoom in and out of the map.
  • The home button takes you back to the default view. If you click on a particular point on the map, a pop-up will be displayed that lists the site’s town, stream, and description. It also shows a data table with the data collected for each point so far. You may need to use the scroll bar on the right side of the pop-up to view the data.

Click here for a larger view of the map.