Roberta Carvalho, Science Director

Volunteers Kiri Peirce and Ron Price help with sampling.

WRWA has been sampling the River to test for fecal coliform bacteria since 1991; monitoring for the presence of bacteria pollution. Bacteria do not generally damage the ecosystem, but can make people sick when they eat tainted seafood, or  swim in contaminated water. They are also a marker to identify the possible presence of other pathogens that come from the same fecal sources. Bacteria in the River comes from human wastewater and domestic and wild animal waste

You can visit our website weekly to see water testing results for the Westport River.Go to this link:  http://westportwatershed.org/river-info/water-resources/ 

The laboratory tests are done by the City of New Bedford Health Department Lab. WRWA's collection and analysis of samples has been utilized by the town and state agencies to document bacterial contamination in the river. WRWA's data is not used to open and close shellfish areas, this sampling is done by the State Division of Marine Fisheries.

Water quality testing results for local public beaches can be found on the state's website:

http://mass.digitalhealthdepartment.com/public_21/maps.cfm?map=Buzzards%20Bay

Bacteria/pathogen pollution is transported to the river primarily by rainfall and resultant runoff. The amount, duration, intensity, and time span between rain events are factors that influence fecal coliform levels in the river. Rainfall is responsible for washing fecal coliform into the river. The amount of rainfall directly affects the amount of fecal coliform in the river. During periods of drought, fecal coliform counts in the river tend to drop significantly. When there is prolonged or large amounts of rain, the effect on fecal coliform is two-fold. First the increase in rainfall simply adds more fecal coliform to the river. Second, the rain decreases the salinity in the estuary, making it more favorable for bacterial growth. Temperature affects fecal coliform growth only when it is extremely cold. In January and February, bacterial growth is inhibited as a result of the cold water temperatures. In the months of May through December, temperature does not seem to play a role in limiting or fostering bacterial growth. During this period the amount of rainfall is the most important factor.

Looking back at the last twenty years of WRWA's monitoring, conditions are greatly improving. These improvements have allowed state shellfish regulators to change the segments for the opening of conditional closures shellfish beds. This increases the availability of shellfish harvest potential.