The first Citizen Water Monitoring Network (CWMN) sampling event of the year took place on Thursday, May 19. Our volunteers helped to sample from 41 different sites within the Neponset Watershed, and the below map illustrates the bacteria results we received.

Red and orange dots on this map indicate areas along the watershed that are not safe for swimming by the state’s bacteria standards. Particularly high sites this month include MEB001, PTB035, PTB047, PUB022, UNB014, and UNB016, which exceed the “swimmable” standard.

In the 72 hours before this month’s sampling, the watershed received 0 inches of rain prior to sampling, which is referred to as dry sampling conditions.

Rainfall creates runoff from parking lots and other hard surfaces which makes its way into the watershed and results in the higher bacteria counts. Rain before sampling allows pollution on roads, parking lots, and driveways to make its way into streams and rivers which is why we tend to see higher bacteria during wet sampling conditions

For a detailed view of the bacteria results, as well as other water quality indicators such as pH, nitrogen, phosphorus, and ammonia, click here.

If you have any questions about the data, or want to become a CWMN Volunteer, please contact Field Sampling Coordinator, Meghan Rauber, at 781-575-0354 x306 or meghan@neponset.org.

We are excited to welcome five new volunteers to this year’s CWMN season.  Thank you to all of our volunteers who helped with sampling this month!

Meghan Rauber, Field Sampling Coordinator, May 2016