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Cambridge Public Health Department Issues Public Health Warning: Avoid Contact with the Alewife Brook in Cambridge due to Potential Harmful Bacteria and Other Pollutants

Avoid Contact with the Alewife Brook in Cambridge Due to Potential Harmful Bacteria and Other Pollutants


Warning in effect until 5 AM, January 28, 2023

People and pets should avoid contact with the Alewife Brook and parts of the Mystic River from January 26-28 due to the release of stormwater mixed with sewage into the brook.

The release of mixed stormwater and sewage—known as a “combined sewer overflow (CSO)”—is needed to prevent contaminated water from backing up into homes, businesses and city streets.  

The CSO release occurred in Alewife Brook Reservation in North Cambridge. It began at 2:05 a.m. and ended at 4:15 a.m. on Thursday, January 26.  This warning is in effect until 5 a.m., Saturday, January 28, 2023.   

Impacted areas may include the Alewife Brook and Little River in Cambridge, Somerville, and Arlington, as well as the Mystic River from the intersection of Alewife Brook Parkway and Mystic Valley Parkway in Somerville to the Fellsway/Route 28 bridge in Medford (near the Mystic River State Reservation).

The public should avoid contact with impacted areas of the Alewife Brook and Mystic River for 48 hours from the time the overflow ends because of increased health risks due to bacteria or other pollutants carried by the stormwater, such as fertilizers or pesticides.  Contact with this water can make you and your pet's sick.  Avoid paddle boarding, boating, fishing, or other activities that can bring you in close contact with this water. 

Information about Cambridge CSO events are posted on the Cambridge Department of Public Works (www.cambridgema.gov/CSOReport) website.  Additional information is available on the Massachusetts Water Resources Authority (https://bit.ly/MWRA-CSO-Notifications) and City of Somerville’s websites (https://www.somervillema.gov/cso). Translations of the web pages are available using the translate box along the top of the websites. 

The City of Cambridge continues to make major improvements to the city’s sewer and stormwater systems.  As a result, there are fewer CSO events than in the past, but they still occur after heavy rain.  To learn more, please visit:www.cambridgema.gov/csoPlanning  

If you have questions about potential health risks from contaminated water, contact Sam Lipson at the Cambridge Public Health Department at slipson@challiance.org or 617-665-3838.

This article is available online on the Cambridge Public Health Department website.

Translated Information

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ለበለጠ መረጃ፣ እባክዎን ድህረ ገጾቹን ይጎብኙ። በቀኝ በኩል በላይኛው ጥግ ላይ ያለውን “Translate” የሚለውን ሳጥን ይፈልጉ እና ቋንቋዎን ይምረጡ




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Page was posted on 1/26/2023 10:23 PM
Page was last modified on 1/26/2023 10:31 PM
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