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Did You Know?

BWSC’s water is considered “soft” (has a lower mineral concentration-calcium and magnesium). This usually means less dishwashing soap, laundry detergent, or other soaps are needed.

Stormwater Management

stormwater outfall
Stormwater Outfall at Metropolitan Ave. Hyde Park

The stormwater system is a separate system that collects water from storm water runoff (rain and snow melt) and discharges it into receiving waters around Boston. Boston Water and Sewer Commission (BWSC) controls most of this system, however, some storm drains and outfalls are privately owned or are owned by agencies such as the Massachusetts Highway Department, the Massachusetts Turnpike Authority, Massport and the Department of Conservation and Recreation.

BWSC’s storm drainage system consists of approximately 424 miles of storm drain, 201 storm drain outfalls and 31,752 catch basins. Approximately 57 percent of Boston is served by separate storm drains. The remainder of Boston is served by combined sewers, sanitary sewers only or is open space with no sewers or drains.

Discharges to BWSC’s separate storm drainage system are regulated under U.S Environmental Protection Agency’s (EPA) National Pollutant Discharge Elimination System (NPDES) Stormwater Permit Regulations. BWSC’s NPDES Stormwater Permit MAS010001 became effective on October 29, 1999.

Under the Permit, BWSC is required to develop and implement stormwater pollution prevention and management programs that are designed to reduce the discharge of pollutants to the municipal storm drainage system to the maximum extent practicable.

In addition, BWSC is required to report annually to the EPA and the Massachusetts Department of Environmental Protection (DEP) regarding the status of its pollution prevention and stormwater management programs. This annual report provides a summary of stormwater management activities undertaken by BWSC, including descriptions of the outfall screening, monitoring and illegal connection remediation programs. Also included are BWSC’s annual expenditures for stormwater programs and assessments of structural controls.

For more information on the Stormwater Annual Report and other related issues, please see the following links: