MWRA monitors the water quality of Boston Harbor and Massachusetts Bay, measuring nutrients,
pathogens, metals, organics, solids, pH, oil and grease, and toxicity. See the What's New page for the latest water quality information and reports.
MWRA's NPDES discharge permit requires compliance reports on several measures of effluent quality and system maintenance. This is intended to control water pollution and ensure compliance with the federal Clean Water Act.
MWRA monitors in Massachusetts Bay to assess the impacts of sewer system and treatment
plant discharges. Parameters measured are nutrients, organic material, toxic contaminants,
pathogens, bacteria, and solids. There is also monitoring in Cape Cod Bay.