HAVERHILL — The sanitary sewer overflow into the Merrimack River has stopped after crews installed a temporary bypass system at Haverhill’s South Mill Street Pumping Station, city officials announced Wednesday, July 1.
According to an update from Haverhill Mayor Melinda Barrett’s Office, the emergency discharge ended after contractors completed the first 24-inch temporary bypass pipeline, allowing wastewater to again be conveyed from the South Mill Street Pumping Station to the Haverhill Wastewater Treatment Plant.
Mayor Barrett said the discharge began after a 42-inch sewer force main failed during a torrential rainstorm on the evening of June 27. The force main carries most of Haverhill’s wastewater from the South Mill Street Pumping Station to the city’s wastewater treatment plant.
“During the emergency response, crews discovered a second break in the force main, requiring a more extensive repair effort,” Mayor Barrett said.
Current dry-weather wastewater flows are now being fully conveyed to, and treated at, the wastewater treatment plant.
“Stopping the discharge into the Merrimack River has been our highest priority since this incident began,” Mayor Barrett said in the update. “Contractors and engineers have worked around the clock over the past several days to make this happen.”
Mayor Barrett said that construction is continuing on a second temporary 24-inch bypass pipeline, which will increase the city’s temporary bypass capacity to approximately 30 million gallons per day.
Once completed, Barrett said, the second bypass line is expected to allow the city to convey much of the wet-weather flow while permanent repairs are made to the damaged force main.
“With the first bypass line now operational, crews will continue preparing for permanent repairs to the damaged 42-inch force main,” Mayor Barrett said. “Additional work includes continued bypass construction, excavation at the break locations, engineering evaluation of the damaged pipeline, and a comprehensive inspection of the force main before permanent repairs are finalized.”
Although the discharge has ended, residents and recreational users are still advised to avoid contact with the Merrimack River near Haverhill and downstream for at least 48 hours, or until public health officials recommend otherwise, due to the potential presence of elevated bacteria and other pollutants from the recent sanitary sewer overflow, Mayor Barrett added.
Mayor Barrett said sewer service to residents and businesses remained fully operational throughout the emergency response, and Haverhill’s drinking water system was not affected.
Mayor Barrett said the city coordinated with the Massachusetts Department of Environmental Protection, the U.S. Environmental Protection Agency, local health officials, and conservation officials throughout the response.
