The Massachusetts Water Resources Authority's multibillion-dollar Metropolitan Tunnel Program will go before the Needham Conservation Commission on Thursday, Aug. 27, for a continued wetlands hearing that marks the program's first local wetlands filing in town.

The commission will also take up proposed revisions to Needham's Wetlands Protection Bylaw at the same meeting, scheduled for 7 p.m. at the Public Services Administration Building, 500 Dedham Ave., according to the town's meeting agenda.

The tunnel filing

The MWRA filed a Notice of Intent under DEP File #234-974, which first appeared on the commission's Aug. 13 agenda and continues Thursday. The filing triggers a formal review of how the tunnel program's construction will affect wetland resource areas in Needham.

The Metropolitan Tunnel Program calls for roughly 15 miles of deep rock tunnels, 10 to 12 feet in diameter and running 200 to 500 feet underground, to provide backup for the aging system that carries about 60% of metro Boston's daily water supply. The existing tunnels, built between 1950 and 1976, have no redundancy. A catastrophic water main break in Weston in May 2010 forced a boil-water order for approximately 2 million people.

Needham is central to the construction plan. Two large launch shafts will be dug in the cloverleaf where Route 128 meets Highland Avenue, requiring controlled blasting through bedrock. The MWRA has estimated about 150 trucks per day will use Route 128 to haul excavated rock during construction, and Eversource will install approximately 1.7 miles of new underground duct banks and cable in Needham to power the tunnel boring machines.

"This is really a once in a generation program that will provide benefits for years and years to come," Kathy Murtagh, the MWRA's director of tunnel redundancy program, said at a February 2025 public meeting in Needham's Powers Hall, as reported by the Needham Observer.

The MWRA's capital improvement plan has estimated the program at $2.1 billion, based on its proposed fiscal year 2025 budget. Construction on the South Tunnel is planned to begin in approximately 2027-2028, with the full project expected to wrap up by 2040.

Bylaw revisions

Separately, the commission will discuss proposed changes to the Needham Wetlands Protection Bylaw, Article 6 of the town's general bylaws. The revisions under consideration include adding riverfront and vernal-pool protections, clarifying a 50-foot no-disturb zone and creating an administrative path for small test pits. Commissioners have also been reviewing draft stormwater rules.

The commission, chaired by Dave Herer and staffed by Director of Conservation Deb Anderson, last discussed the bylaw edits in May.

How to attend

Thursday's hybrid meeting begins at 7 p.m. in the Charles River Room at 500 Dedham Ave. Residents can also join via Zoom using Webinar ID 856 7743 6569. The next scheduled meeting is Sept. 10 at 7 p.m.