The municipalities surrounding Boston Harbor are requesting that the Commonwealth of Massachusetts designate the waters of Boston Harbor as a No Discharge Area (NDA) pursuant to the Clean Water Act, Section 312(f)(3). An NDA is a body of water in which the discharge of vessel sewage, whether treated or not, is prohibited. The No Discharge Area would be called the Boston Harbor No Discharge Area.
While the waters of Boston Harbor are under the jurisdiction of a number of different municipalities, water quality issues affect the harbor as a whole. Past efforts to clean up the harbor have occurred across municipal boundaries and efforts to reduce vessel sewage inputs to the harbor should be addressed in a similar fashion. The fact that boating activity in the harbor also crosses municipal boundaries suggests that a harbor-wide approach is the most appropriate.
Vessel sewage, like many other pollutants, can be harmful to the environment when it is not adequately treated. Sewage contains high concentrations of nitrogen, a substance that can lead to algal blooms and low dissolved oxygen concentrations, which in turn can affect the health of fish, shellfish, and eelgrass beds. Sewage also contains bacteria and viruses that can make shellfish unsuitable for human consumption, can be a risk to human health and can severely restrict recreational opportunities (e.g. when swimming is prohibited at beaches due to elevated fecal coliform levels).
City of Boston Environment Department; City of Quincy Harbormaster; Urban Harbors Institute, University of Massachusetts Boston; and Charles River Watershed Association, "An Application for a State Designated, Federally Approved No Discharge Area for Boston Harbor, MA" (2008). Urban Harbors Institute Publications. 10.