Five towns in southern New Hampshire will start getting drinking water from Manchester by the end of 2020.
That's according to an agreement finalized this month among members of the new Southern New Hampshire Regional Water Project.
The SNHRW members are: Manchester Water Works, Derry, Plaistow, Windham, Salem, and utility companies in Hampstead and Merrimack.
The agreement spells out the timeline for building a network of water mains, pumps, and tanks that will route water from Manchester's Lake Massabesic and the Merrimack River through Derry to Salem and surrounding towns.
Erin Holmes, an administrator with the New Hampshire Department of Environmental Services overseeing the project, says it will be the state's largest water distribution system to date.
"Some municipalities have an emergency connection with their neighbor, but never is something daisy-chained like this where you're linking everybody together with the goal of providing safe reliable drinking water down the line," she explained.
Towns say they need the additional water because of the region's growing population and contaminants found in local wells.
Towns will receive a total of up to 1 million gallons of water per day from 2020-2023, and 3 million per day after 2023.
Towns will pay for construction with $27 million from a settlement between New Hampshire and polluters responsible for the chemical additive MtBE, which has been found in groundwater throughout southern New Hampshire.
"That's the selling point," Holmes said. "You're getting all this infrastructure for free."
Metering stations in each town will measure how much water residents are using, and towns will be charged at a rate spelled out in the agreement.