Somerville And Cambridge Working To Stop Charles River Pollution

SOMERVILLE, MA — The city worked with Cambridge and the Massachusetts Water Resources Authority to present potential solutions to mitigate combined sewer overflow in the Charles River.

CSO occurs when heavy rainfall causes the shared pipes containing both stormwater and wastewater to overflow and release into a body of water. According to the Charles River Watershed Association, The main option presented by Somerville, Cambridge, and the MWRA was a CSO storage tunnel, similar to one in South Boston that first opened in 2011. Green stormwater infrastructure was also suggested in addition to the tunnel.

“GSI provides numerous co-benefits, such as reducing flooding and urban heat impacts, improving air and water quality, and beautifying neighborhoods,” the CRWA explained.

In 2023, 72 million gallons of CSO water entered the Charles River. The ultimate goal of the entities is to make it swimmable again in the future.