The owner of the Penobscot River dam that shut down in July after a transmission crossarm broke and likely killed thousands of fish said it is replacing faulty poles along the 30-mile power line.
Brookfield Renewable N.A. said the new poles are part of an annual maintenance program it has run for 10 years. In that time, failures on the line have twice caused automatic shutdowns of the Ripogenus Dam that left thousands of fish dead from a lack of water, according to the Maine Council of Trout Unlimited.
The work comes as federal regulators near a decision on renewing the dam’s license. The July fish kill brought a new round of complaints from conservation groups and nearby landowners who say Brookfield has let maintenance slide. The Federal Energy Regulatory Commission has asked the company to account for every repair on the line since 2016.
The July crossarm failure sparked a small fire that shut down the dam, which is roughly 30 miles west of Millinocket. The earlier shutdown came in 2023, after lightning struck poles and other equipment at McKay Station, the hydroelectric plant tied to the dam.
Great Lakes Hydro America, the Brookfield subsidiary that operates the dam, is the license applicant. Trout Unlimited is among the many groups and landowners that have filed comments with the commission, much of it about maintenance and irregular water flows. Trout Unlimited and dam neighbors told regulators the crossarm failures show Brookfield is not keeping up.
Brookfield has told federal regulators it spent $3 million on maintenance to improve reliability. Trout Unlimited questioned that figure in its filing, pointing to the two recent failures.
In an Aug. 27 letter, the commission asked Brookfield for an itemized accounting, by location and date, of all inspections, maintenance and rehabilitation work on the transmission line since 2016. The company has 60 days to respond.
Brookfield spokesperson David Heidrich told the Bangor Daily News that the annual maintenance is meant to reduce risk and improve reliability, but it cannot rule out an unexpected failure. He compared it to a car owner who keeps up with inspections and service and still has a mechanical problem.
The crossarm failures “should not be viewed as evidence that the program was inadequate, but rather as recognition that even well-maintained infrastructure can experience unexpected failures,” Heidrich said.
In a July 31 filing with federal regulators, Brookfield said the crossarm broke because of “age-related internal deterioration” that could not be seen from the outside.
McKay Station is shut down in the evenings through Oct. 10 for seasonal maintenance, including work on the transmission lines, and will be shut again in December, Heidrich said. During those outages, water will be released through deep gates at the dam and routed through the upper gorge.
Lori Valigra reports on the environment for the BDN’s Maine Focus investigative team. Email her at lvaligra@bangordailynews.com. Support for this reporting is provided by the Unity Foundation, a fund at the Maine Community Foundation and donations by BDN readers.