Massachusetts Bay Bacteria: MWRA monitors bacteria at locations surrounding the MWRA outfall and elsewhere in Massachusetts Bay (see station map). Water samples are analyzed for sewage indicator bacteria: fecal coliform and Enterococcus.

Map of bacteria monitoring locations.
__________________________________________________________________________
Boston Harbor and Rivers: Boston Harbor is an estuary--a marine ecosystem where fresh water from the rivers enters the ocean. Since 1989, the Massachusetts Water Resources Authority (MWRA) has measured bacteria, algae, water clarity, dissolved oxygen, nutrients, and suspended solids at more than 70 locations in the Harbor and the Charles, Neponset, and Mystic rivers. Download data below.