In the spring of 2024, sonar imaging detected roughly 10,000 American shad gathered below the Brunswick-Topsham Dam on the Androscoggin River. To continue their migration to their spawning grounds, the shad must ascend a fish ladder — a stairway-like structure built to enable fish passage. Of the thousands of fish observed at the base of the dam, just 91 made it through. A year earlier, that number was only 14.

Centuries ago, the Androscoggin River boasted an extraordinary abundance of fish. Atlantic salmon, river herring, shad, sturgeon and several other species migrated each year from the ocean to what was then Brunswick Falls, continuing upriver as far as Lewiston to spawn. By the early 1800s, however, dams built to power industries like grist, lumber, textiles and paper disrupted the river’s natural flow and blocked fish passage.

Today, the Brunswick-Topsham Dam is owned and operated by Brookfield White Pine Hydro, a subsidiary of the multibillion-dollar global energy company Brookfield Renewable. While full information about the economics of the dam is not publicly available, the company has reported that the dam generates as much electricity annually as could be used to power about 13,500 homes. Brookfield sells this energy for profit on the grid.

While the construction of the dam in 1983 included a fish ladder to support the movement of migratory fish, the ladder is alarmingly inadequate, limiting or blocking the passage of hundreds of thousands, if not millions, of fish each year. Scientists estimate that the Androscoggin River can support the annual production of 3.7 million river herring. Yet between 2000 and 2023, the fishway has only passed an average of 71,000 herring each year, just 1.9% of its potential productivity.

The National Oceanic and Atmospheric Administration has echoed concerns over the dam’s negative impacts on fish migration. In a 2020 report, the agency referred to the “upstream and downstream fish passage facilities” at the Brunswick-Topsham Dam as “largely ineffective” when it came to enabling the safe passage of fish like shad, alewives, herring and salmon.

But it’s not too late to address this challenge and restore healthy populations of migratory fish. The dam’s federal license is up for renewal in 2029, and we’re proposing a number of potential solutions to improve fish passage — from major fishway upgrades to redesigning or removing the dam. The Federal Energy Regulatory Commission (FERC) is the independent agency that licenses, regulates and oversees energy industries in the economic, environmental and safety interests of the American public. FERC must consider public input and is key to making changes in how dams operate and fish passage is improved.

The Brunswick-Topsham Dam is the first barrier that migratory fish face on the Androscoggin as they attempt to access their spawning grounds, but it is just one of a complex series of challenges for the 11 species of fish that live in Maine’s second largest river, which includes endangered Atlantic salmon. Improving fish passage at the dam is a key step in a larger effort to restore the health of the river ecosystem and the species that rely on it.

FERC is now evaluating whether or not to issue a new license to Brookfield that will run for another 40 or 50 years. Relicensing is a years-long, complex process, and it’s also our only realistic opportunity to require significant changes to the current design and functions of the dam and fish ladder. The Androscoggin River is a shared public resource, and yet private industry profits are being prioritized over the health of the river. We must balance the need for power generation with the needs of the river and its inhabitants, and return the Androscoggin to its status as a healthy and vital part of the communities that it defines.

Our newly formed coalition, Free the Andro, seeks to provide a voice for migratory fish, and is committed to working with all parties to remove obstacles so native fish can reach their historic spawning grounds. The founding members of this coalition — Maine Rivers, American Rivers and the Merrymeeting Bay Chapter of Trout Unlimited — along with many other groups and individuals, are working to ensure that the next 50 years will be a time of renewal for the river, the wildlife that depend on it and the communities that prosper along its shores.

“Nature Connects” is a monthly column showcasing conservation stories from people and organizations across Maine. To learn more or suggest story ideas, email reply@mcht.org.