Sustainable Arlington

An Envision Arlington committee & a Mass. Climate Action Network (MCAN) chapter

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pdf MWRA Final CSO Performance Assessment Report

Task 6: Final CSO Post Construction Monitoring Program and Performance Assessment Report.

December 30, 2021  [231 pg]  Mass. Water Resources Authority (MWRA)

default MWRA's CSO (Combined Sewer Overflow) Reporting: Alewife Brook

Tagged in AlewifeBrook, CSOs, pollution, stormwater

A combined sewer overflow (CSO) occurs when a large storm overwhelms the sewage system causing rainwater to mix with wastewater and discharge to a nearby water body. This relief measure prevents sewage backups into homes and businesses. MWRA owns combined sewer outfalls that discharge to the Charles and Mystic Rivers, Alewife Brook, and Boston Harbor. When a CSO occurs at an MWRA-owned outfall, there is a notification displayed on the map below.

The cities of BostonCambridgeChelsea and Somerville manage their own combined sewer outfalls, including CSO reporting. These communities must be contacted directly for information regarding their CSO discharges. To see where all CSO outfalls are located, download this map of MWRA and community CSO sites.

Public health officials recommend avoiding contact with water bodies during rainstorms and for 48 hours afterwards, as there may be increased health risks due to bacteria or other pollutants associated with urban stormwater runoff and CSO discharges.

Subscribe to MWRA CSO discharge notifications

default Assesses MWRA's Final CSO Performance Assessment Report

Tagged in AlewifeBrookCSOs

The MWRA (MA Water Resources Authority) has published its Final CSO Performance Assessment Report, using modeled data, rather than real numbers. The true data is EIGHT TIMES WORSE than the MWRA's modeled data, meaning that the MWRA's CSO report for the Alewife is off by 43 million gallons of sewage water.

Read more:

Please sign the Petition to End Sewage Pollution and Flooding in the Alewife and sign up for their newsletter here: