The Water Resources Authority said the overflow happened around 8:30 p.m. on Nov. 30 after a vicious storm hit the area with heavy rains and high winds. Water upstream of North Washington Street Bridge should be avoided for two days minimum.
"The public is advised to avoid contact with affected water bodies for at least 48 hours after a sewage discharge or overflow, during rainstorms, and for 48 hours after rainstorms end, due to increased health risks from bacteria or other pollutants associated with urban stormwater runoff and discharges of untreated or partially treated wastewater.," the warning said.
The overflow wasn't an accident. It's a design feature to protect people's property. When heavy rains overwhelm the system, the discharge prevents sewage from backing up in homes and businesses, authorities said.
Updates and other warnings are posted on Massachusetts Water Resources Authority's website.
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