As Part Of EPA Agreement, Manchester To Alert Residents When Sewage Discharged Into Merrimack River

Aug 12, 2019

Manchester put 364 million gallons of combined wastewater and stormwater into the Merrimack River in 2018.
Credit Army Corps of Engineers, New England District

The Environmental Protection Agency is requiring the city of Manchester to alert residents when it discharges raw sewage into the Merrimack River. The change is part of a large agreement Manchester is finalizing this year with the EPA to ensure the city's wastewater and stormwater systems comply with the 1994 Clean Water Act. 

By September, the Department of Public Works plans to publish on its website every time its system discharges stormwater and wastewater into the Merrimack. The discharge - called a "combined sewage overflow" or CSO - occurs after heavy rainfall. In 2018, there were 177 CSO events, which put a total of 364 million gallons of dirty water - including untreated sewage - into the Merrimack River. 

Under the new agreement with the EPA, Manchester will not include the volume of discharge nor the prevalence of bacteria. Environmental advocates say it's a first step but not enough.

"Notifying people is more of an indicator that 'Hey, an event happened; you might want to consider not being in the water because of it,' but more important would be testing," says Dan Graovac, director of the Merrimack River Watershed Council in Lawrence, Massachusetts, which occassionally tests bacteria levels in Merrimack after CSO's.

Frederick McNeill, Chief Engineer with the Department of Environmental Protection at Manchester’s Department of Public Works, says the Merrimack river's speed and size typically dilute the discharge to a safe level, and that regular testing for bacteria would be prohibitively expensive.

The city has spent $58 million dollars in the last 10 years to reduce discharge into the Merrimack, but it needs $212 million more to finish up the job.

McNeill say under the pending agreement with the EPA, Manchester will be required to eliminate all discharge into the river in the next 20 years. He says he is "cautiously optimistic" that members of the N.H. Congressional delegation will help Manchester secure federal grants to help with the cost, but that much of the expense will fall to the city and state.