Water Quality
Stellwagen Bank

divers installing equipment
NOAA divers and the AUK. Credit: Matthew Lawrence, SBNMS, NOAA

Why is it a concern?

Water quality can be impacted by the presence of contaminants (for example pesticides, hydrocarbons (e.g., oil), and heavy metals), excessive sedimentation, and elevated nutrient loads. Much of the contaminants and pollution reaching the sanctuary comes from non-point sources or from distant-point sources. Several waste water treatment facilities discharge into Massachusetts Bay to the north and south of the sanctuary, the largest being the Massachusetts Water Resources Authority (MWRA) Boston Harbor outfall located 9.5 miles from Boston and 12 miles west of the Stellwagen Bank sanctuary border. Air pollution from power plants comes from as far away as the Midwest. A variety of chemicals move from the air to the water where they can be accumulated by organisms. In addition, the region is heavily traveled by commercial and recreational vessels and cruise ships that discharge wastes during their voyages. Other sources of contamination include clean material disposal at the Massachusetts Bay Disposal Site, and disturbances during the laying of underwater pipes and cables (only one of which crosses the sanctuary). Of concern are the cumulative impacts of multiple activities that may affect the resources of the sanctuary.

Overview of Research

Project Name PI and contacts Links

Water quality

Michael Mickelson


Science Needs and Questions

  • What is the Sanctuary’s water quality and how does water quality change over time?
  • Does the Boston sewage outfall impact water quality in the Sanctuary?
  • Does discharge from the Boston Sewage Outfall impact commercial fish resources?
  • Does discharge from vessels using the Sanctuary impact water quality?
  • Does discharge from the Merrimack River impact water quality in the Sanctuary?
  • How can these data be used to inform policy decisions on water quality issues?


U.S. Department of Commerce. National Oceanic and Atmospheric Administration. Office of National Marine Sanctuaries. 2010. Stellwagen Bank National Marine Sanctuary Final Management Plan and Environmental Assessment. Silver Spring, MD.

National Marine Sanctuary Program. 2007. Gerry E. Studds Stellwagen Bank National Marine Sanctuary Condition Report 2007. U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Sanctuary Program, Silver Spring, MD. 41 pp.