Merrimack River

The EPA said Manchester alone accounts for about half of all combined sewer overflows in the Merrimack River.

The wettest summer on record in New Hampshire resulted in historic levels of raw sewage and stormwater runoff flowing into the Merrimack River last year, data obtained by Merrimack River Watershed Council shows.

More than 2 billion gallons of Combined Sewer Overflow (CSO) — raw sewage mixed with runoff from urban street drains — were discharged into the river from five cities along the Merrimack.