CMP has applied to the Maine Public Utilities Commission for a Certificate of Public Convenience and Necessity to build Phase 1 of the "Greater Portland Transmission Upgrades" — new and rebuilt high-voltage lines and two new or expanded substations running through Cumberland, Falmouth, Portland, Westbrook, and Yarmouth. In several of these neighborhoods, this would be the first time high-voltage transmission infrastructure has been sited there at all, rather than an upgrade of an existing corridor residents already live alongside.
Intervenors have also filed formal data requests asking CMP to state, in plain language, exactly how close energized 115kV wires will come to homes — including any home located near or under the line — and whether CMP has assessed places where the standard clearance can't be met, including near school bus stops where children wait outdoors.
Landowner intervenors in the case — represented informally as the Falmouth Corridor Intervenors — have formally challenged whether this project is needed at the scale CMP proposes. This isn't an abstract dispute over kilowatts: if the load forecast behind a $547 million, multi-town transmission project is wrong, our neighborhoods absorb permanent clear-cutting, 90–120-foot towers, and property value loss for infrastructure that didn't need to be built this way. Their motion argues the forecast relies on the same 2024 ISO New England methodology that Maine's own Office of the Public Advocate has already flagged for overestimating electric-vehicle and heat-pump adoption. The Commission's July 15, 2026 order expressly left that question open for this case.
Even if some upgrade is warranted, CMP has not shown it seriously evaluated less destructive ways to deliver it — undergrounding, battery storage, demand response, or other alternative transmission technologies. State law requires a genuine non-wires-alternatives review before new overhead lines go through residential neighborhoods; we don't think CMP has done one.