North, South Village wastewater plans proposed for Londonderry

By Cynthia Prairie
©2024 Telegraph Publishing LLC

The Dufresne Group of Springfield has recommended two community wastewater disposal systems for the North and South Villages of the town of Londonderry.

Christina Haskins, a vice president and engineer with Dufresne, presented the engineering company’s findings and recommendations last Wednesday before a group of residents and business owners at the Town Office Building.

Haskins told the audience that the plan is currently at 60 percent toward completion. Town administrator Shane O’Keefe told The Telegraph that 90 percent of the plan is expected to be finished in the next few weeks. Haskins emphasized thay, “The alternatives and costs are still evolving.”

The town has been looking at ways to use two allotments of funding totaling $7.9 million, through the American Rescue Plan, designated for affordable and safe wastewater services to residential and commercial property owners.

The site that Dufresne identified in the North Village is a privately owned parcel that could handle 6,490 gallons of wastewater a day, with the possibility of expansion to 8,000 gallons. At its base level, it would handle 23 residential or residential and commercial properties, with a cost estimate is $2.9 million.

She said that not all “priority parcels” would be able to connect and suggested cluster systems, which group together nearby buildings and their septic tanks into a single drainage field, to fill in the gaps.  Priority parcels are within a flood plain or flood way or provide “critical services to the town.”

The project would be a liquid-only sewer with smaller pump stations and drip disposal and would service many Main Street businesses and homes that have been subjected to recent flooding. The drip system is considered highly effective and moves wastewater slowly through drips. Each property would still have a septic tank for solids.

In the South Village, Dufresne has identified the town-owned Prouty property on Route 100, which could handle 6,200 gallons of wastewater a day, with the possibility of 12,000 a day. At its base level it could serve 22 residential or residential and commercial properties. The total cost of the Prouty project is estimated at $4.33 million — about $690 per gallon —  with liquid only sewer with drip disposal.

Haskins said recommendations were made according to cost per gallon and not necessarily the cost for each project overall.

For any expansion to occur at either site, a pre-treatment system would have to be added. An analysis of the properties is currently under way to see if expansion is possible. But adding capacity will allow for additional connections to each.

Haskins said Dufrense discarded the idea of a centralized wastewater treatment plant, which for 1,500 connections could cost of $14,000 per household. She said it would be more than is needed for Londonderry, adding that a downsized facility to accommodate 140 connections would require a $12.5 million facility that would cost $90,000 per connection. She further explained that the smaller the facility, the higher the per-household cost.

There are deadlines the projects must meet: The money for the work has to be obligated by Dec. 31, 2024 and spent by the end of 2026.

Londonderry’s Select Board will ultimately make the decision on the how the user fees are structured and that will depend on the final costs. The local share will have to be covered by other grant funding or a bond vote, which the board is currently planning to vote on on Monday, Jan. 22. Residents will vote on the bond vote, currently planned for Town Meeting Day, Tuesday, March 5. If the bond is approved, the Select Board will then set up an administrative structure for the system.

The North and South Villages are two separate projects with separate fundings that cannot be used one for the other. They can move forward separately.

Haskins told the audience that the state is concerned that a single town may not be able to construct two separate projects of this magnitude. But O’Keefe told The Telegraph that both projects were funded, and “I think we should move forward on both projects.”

O’Keefe added that in villages such as Londonderry’s “there is limited space for what you can do with septic. However, this will enable a business to locate or expand without worrying about septic.”

Attempts to reach Haskins for further comment on Tuesday were unsuccessful.