The fish die-off that followed a Penobscot River dam shutdown in July rallied calls for stiffer regulations on the dam’s owner, which has been accused of repeatedly disrupting the water levels at a nationally renowned fishing and whitewater rafting destination.
Brookfield Renewable, an offshoot of a multibillion-dollar conglomerate, is in the final stages of relicensing the Ripogenus Dam, about 30 miles west of Millinocket. The July 27 turbine shutdown, triggered by a broken transmission line cross-arm at McKay Station, followed a similar incident in 2023, and was catastrophic for juvenile landlocked salmon, the state fish.
Brookfield would like to stick with the terms of its current license. But the successive malfunctions have led to accusations of poor maintenance and calls for greater oversight, according to a Bangor Daily News review of complaints filed with federal regulators by local property owners and conservation groups.
The 30-year-old license that Brookfield inherited from the dam’s previous owner is weak on protecting wildlife and needs additional provisions for a backup system that would reduce dramatic water flow changes, many argued. The company has never received license violations despite the ongoing concerns about the dam’s impact on the surrounding environment.
“An event happening this close to the end of the [licensing] process shows there’s a need to set some higher standards to prevent this from happening,” said Chris Howe, a local whitewater raft guide.
The Ripogenus Dam was a key part of Brookfield’s hydropower expansion in Maine when it bought the dam and transmission station in 2010 from the now-shuttered Great Northern Paper Company. The conglomerate, which also runs solar, wind and distributed energy operations worldwide, now owns about 90% of the power-generating capacity from dams in the state.
A coalition of environmental groups tried in 2023 to sue Brookfield over die-offs of Atlantic salmon in the Kennebec River, but it withdrew the lawsuit after federal regulators ruled the fish could coexist with the hydroelectric dams on the river. Last fall, the company struck a historic deal to sell the dams to The Nature Conservancy, which plans to eventually remove them.
Ripogenus Dam is located on the West Branch of the Penobscot River, an area valued for recreation and breathtaking views. The area contributed nearly $2 million in economic impact to the state in 2025, according to the Maine Council of Trout Unlimited’s angler survey.
Shutdowns and fish kills were not common when it was owned by Great Northern because the paper mill ran an even flow of water all day, Kathy Houston, a member of the nearby Caribou and Chesuncook Camp Owners Association, said.
But turning the dam into an electricity-generating business changed that, because Brookfield controls flows so they correspond with the most income at a given time, said Houston, who has been following the dam’s re-licensing process since it began in 2021. When a dam’s water flow is high, it can significantly reduce the downstream flow of a river.
Her home on nearby Chesuncook Lake has been so affected by water flow at the Ripogenous Dam that in recent years, there have been times when she and her neighbors couldn’t use their boat ramps to get to the lake, she said.
The July shutdown lasted two hours. An early eyewitness on the scene, Howe wrote to federal regulators that dam system failures have been an annual event during his 18 years as a river guide. He asked regulators to add provisions to the new license to limit low water events caused by malfunctions to 30 minutes to minimize fish die-offs. He also asked for quarterly inspections and maintenance of powerline systems using unaffiliated, local contractors.
Brookfield must report shutdowns such as the two so-called “trip” events that caused water levels to drop below normal levels to the Federal Energy Regulatory Commission and the Maine Department of Environmental Protection. But it does not have to report fish kills suspected to have been caused by the disruptions, the agencies said.
Brookfield’s report after the July event noted that it was continuing a multi-year project to proactively replace poles and cross arms around McKay Station. The company has invested nearly $3 million over the past decade in inspecting, maintaining and rehabilitating the station’s transmission lines, with plans to invest millions more in the coming years, Brookfield spokesperson David Heidrich said.
In the filing, Brookfield said it did not survey the area downstream of McKay Station after the shutdown, but acknowledged that “it is likely that impacts to aquatic life occurred.”
Several thousand juvenile landlocked salmon and other fish may have been killed when the shutdown caused water levels to plummet in a short timeframe, Neal Hagstrom, a former fish biologist who is a member of the conservation group Maine Council of Trout Unlimited, said. He said the fish kill cost $50,000 in lodging, guide services and angler-related activities.
The group wants to see actions to stop future fish kills, which are “totally preventable,” said Steve Heinz, the state group’s FERC action coordinator.
In comments to federal regulators, the group said it wants to see a dam keeper return for a faster response to problems, to see a consistent flow and redundant transmission lines installed between McKay Station and Millinocket. It also would like to see a system added that can automatically restore water flows from a backup source when the generators fail.
“The old license is so lax,” Heinz said.
Although no fines have been issued yet, FERC has the option of fining Brookfield for unplanned outages or other operational issues that may not conform to the license. It can also recommend license amendments. In cases of “egregious non-compliance” it can also stop dams from operation, an agency spokesperson noted.
Brookfield’s license, issued in 1996, expires in September, but state and federal reviews still need to occur before it can be renewed. The deadline to submit public comments to federal regulators is Aug. 28. The Maine Department of Environmental Protection will then start a water quality assessment. It will allow public comments and could take up to a year to complete.
Howe, the rafting guide, said changes to the license are necessary because it will dictate how the dam and the power station will operate for the next 30 years.
“Nobody wants to say they can’t generate power,” Hagstrom, the former fish biologist, said. “All we want them to do is take a few steps to protect what’s there. There’s some easy things they can do.”
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.