A synthesis of case studies from Narragansett Bay (RI/MA, USA) emphasizing implementation of the US Clean Water Act using adaptive management
Over the last 40 years, Narragansett Bay has experienced significant water quality improvements in response to reductions in nitrogen, heavy metal and organic contaminants, and bacterial pathogen discharge. The sources of these pollutants stem from the long history of population growth and a manufacturing-based economy. These reductions were documented by decades of persistent research and are the product of implementing the Clean Water Act by cooperation among all levels of government, utilities commissions, industry, nonprofits, universities, and advocacy groups. Wastewater treatment facilities remain a significant nitrogen source to the bay and continuing evaluation will determine if further reductions are needed. Metals/organic contaminants in sediment remain at or below thresholds for negative biological impacts. In response to pathogen reductions, over 3,000 acres have been reclassified as approved for shellfish growing between 2010 and 2017. The watershed still faces significant challenges in addressing stormwater runoff of both nitrogen and pathogens, and legacy methylmercury contamination in fish. Changes in population and land use and climate change will need to be addressed as well. The highlighted case studies showcase the abilities of public and private entities to collaboratively identify indicators, define problems, track changes, and respond to watershed-scale problems through ongoing adaptive management. Widely sharing successes and lessons learned in Narragansett Bay – from processes to research to management actions – can inform other estuarine collaborative management efforts to address complex and challenging environmental issues.
This report has been peer-reviewed by 24 individuals from NBEP staff, EPA, NBEP's Science Advisory Committee, NBEP partners, and 6 anonymous reviewers from 2 academic journals.
The views expressed in this report are those of the authors and do not necessarily represent the views or policies of the U.S. Environmental Protection Agency or the New England Interstate Water Pollution Control Commission. Any mention of trade names, products, or services does not imply an endorsement by the U.S. Government, the U.S. Environmental Protection Agency, or the New England Interstate Water Pollution Control Commission. The EPA and NEIWPCC do not endorse any commercial products, services, or enterprises.
