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DPW offices at 147 Hampshire St. are open to the public, by appointment only, Monday through Thursday. Appointments can be made by phone at 617-349-4800 or by email at Individual staff are also available for appointments outside of these hours as needed; please contact the office with the details of your issue, and we will coordinate with the appropriate staff member. Many DPW services can be provided online, and DPW phones are staffed 24/7 to respond to urgent concerns.

Notice of Combined Sewer Overflow Discharge

Notice Alert: CSO Activation in Alewife Brook

DATE:  December 1, 2020 

In accordance with the conditions of the Department of Environmental Protection's (DEP) Alewife Brook/Upper Mystic River Variance, we are hereby notifying you that a Combined Sewer Overflow (CSO) occurred at CAM401B on DECEMBER 1, 2020 AT 12:35 AM and discharged into the Alewife Brook.  The Variance approved workplan requires the Cambridge Department of Public Works (DPW) to notify local health agents, DEP, EPA and MRWA within 24 hours of when a CSO event occurs.   This notification does not reflect the absence of any activation at other sites.  Rather, the notice is intended to be confirmation to users of the resource that untreated sewage discharges to the Brook/River have occurred. 

The water quality in Alewife Brook is often impaired due to bacterial and other pollutants from a number of sources, including stormwater runoff, CSOs and cross connections between sanitary sewers and stormwater drains. Water quality in the brook during both wet and dry weather generally fails to meet state bacteria standards for fishing and swimming. Contaminant sources originate in the watershed communities of Belmont, Arlington, Cambridge and Somerville, all of which are undertaking programs to identify and control the sources of pollution to the brook. 

Portions of Cambridge and Somerville are served by combined stormwater and sanitary sewer systems, common in older cities. There are six CSO outfalls on Alewife Brook (see the attached map for locations) which discharge untreated CSO (a mixture of wastewater and stormwater) during moderate and heavy rainfall to relieve the system and prevent sewer backups into homes, businesses, and streets. In addition, bordering communities also have separate drainage pipes that collect stormwater runoff and carry it to the brook. Discharges from CSOs and from separate stormwater pipes include bacteria and other pathogens, oxygen-demanding pollutants, solids and other contaminants. Public health officials recommend avoiding contact with the brook during and for 48 hours following rain storms, as there may be increased health risks during these periods. Contact with floodwaters should also be avoided as they may contain similar contaminants and pose associated health risks. Clean up information following a flood is available on the MA Department of Environmental Protection web site at:  For real-time water data at Fresh Pond Reservoir, you can view the United States Geological Survey National Water System website at: Please contact Catherine Daly Woodbury at 617-349-4818 or James Wilcox at 617-349-6426 if you have any questions. 

CSO Outfalls along the Little River/Alewife Brook 


Page was posted on 12/1/2020 2:21 PM
Page was last modified on 12/1/2020 2:23 PM
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