New England Power presents transmission‑line refurbishment in Charlton; commission requests replication plan and site inspection

New England Power Company’s consultant told the Charlton Conservation Commission that a proposed asset‑condition project will replace aging wooden transmission structures with steel in order to maintain reliability, but the work will require temporary matting and some permanent wetland and riverfront impacts.

Kip Callahan of VHB presented the project for line U173 and W123 and said the Charlton portion spans roughly 2.4 miles. He described construction methods — reflagging wetlands, vegetation maintenance, installing large timber construction mats for access and work pads, drilling foundations and installing steel structures, transferring conductors, and then removing old structures and restoring the site.

Callahan gave quantified impacts in Charlton: about 282 square feet of permanent impact in bordering vegetated wetlands (BVW) and about 4,821 square feet of permanent impact in riverfront area associated with concrete caisson foundations and widened access for cranes and drill rigs. He said some structures will be direct‑embed steel and others will require steel encased in concrete in higher‑stress or wetland locations.

The project is being reviewed as a limited utility project under 310 CMR 10.353; Callahan said the team has coordinated with Natural Heritage on priority habitat areas and is preparing a conservation management plan. He told the commission that DEP provided three substantive comments: it asked that the replication plan and monitoring plan be provided to the commission before approval, questioned whether some access‑road work qualifies as routine maintenance, and requested clarification where access roads coincide with delineated streams. Callahan said the replication and monitoring plan was in preparation and expected by month’s end.

Commission action: members agreed to a site inspection to verify wetland mapping and construction access and voted to continue the discussion to the next meeting so the commission can review the replication and monitoring plan and DEP’s file comments.

Quote: Callahan summarized the scope simply: “This project proposes to replace 60 existing structures with 62 steel structures.”

Next step: the commission will review the replication plan and conduct a site visit; approval will be contingent on DEP comments, the replication/monitoring documentation, and on-site verification.