Maine’s rivers are suffering from the presence of more than 1,000 dams, three-quarters of which produce no power. (Irina Shatilova/iStock photo)

Next time you approach a river, get close to the water. Wade in and lean forward as the current tugs at your legs. Listen carefully and you may hear the river singing a sad song, one we are finally heeding. Maine abuts a vast sea but is also defined by its great rivers. That ocean has been a source of food and wealth, and a means to travel the world for countless voyagers. But our rivers were critical to the settlement of Maine, and they are still incredibly valuable.

Across 400 years we thoughtlessly exploited the rivers. We harvested billions of fish from the waters, thinking the bounty would last forever, but those fish runs disappeared long ago. We reduced rivers to giant log chutes for millions of trees to feed sawmills and shipbuilding. When the Industrial Revolution generated noxious wastes, we dumped them in the rivers. Once we figured out how to build large dams, we were relentless in impeding the natural flow of water in search of cheap power for hundreds of mills. What have we wrought?

Today Maine rivers are choking on more than 1,000 dams, many of them decades old and in poor condition. “Wait,” you say, “those dams generate critical green energy!” Not quite true, according to experts at groups like Trout Unlimited, Maine Rivers, and River Keepers.

Those sources report that only 241 dams in Maine generate power, 75% of that from just 24 dams. In the U.S. we have more than 92,000 dams and only 3% yield power. That is a lot of river blockage, even for the putative benefits like flood control. Most dams are relics from a bygone era, but the damage to rivers and our environment continues unchecked. For instance, scientists estimate that without intervention, the Atlantic salmon that once filled Maine rivers will be extirpated within 10 years. Many freshwater species are in similar straits.

Dams cause thermal and chemical impairment of water that can trigger algal blooms. Rivers are severely impacted by dams, creating major disparities in the habitat above and below the dam. Species that thrived from river source to the sea before the dam are soon disadvantaged, sometimes to the point of extinction.

Riverbeds below dams are irreparably scoured, often accelerating flows at the risk of flood damage. Decomposition of sediments above dams is a major contributor of two greenhouse gases: methane and carbon dioxide. Microbes in impoundments have evolved to convert any mercury to methylmercury, highly toxic to humans and other species.

The general public is starting to realize that the dam era should end and that we must restore our rivers. The turning point occurred in 1999, when the Edwards Dam was removed from the lower Kennebec River. Now, the Maine Department of Marine Resources is partnering with other agencies and organizations to remove more dams on the Kennebec. After billions of dollars have been spent by the Bonneville Power Administration on failed salmon and steelhead recovery plans, several U.S. senators are working to remove power dams along the Columbia and Snake rivers.

The problem is that operating licenses for 1,600 dams are awarded by the Federal Energy Regulatory Commission, and those licenses can run for 30-50 years. Thus, the window for removing a dam is narrow, and the commission has been decidedly unresponsive to concerns of the public.

The Toronto company Brookfield Asset Management owns dozens of dams in Maine and has often resisted proposals to improve or remove outmoded dams. Brookfield has deferred requests to help prevent the loss of migrating fish stocks. The company has sometimes built fish ladders or fish lifts, but the facts show that does not solve the problem. Before 1820, there were upward of 200,000 Atlantic salmon in the Kennebec River. In 2018, a mere 11 salmon were captured and trucked to their native spawning grounds on the Sandy River.

Four hydropower dams on the lower Kennebec have a capacity of 43 megawatts, but they produce about 23 MW, just 1.5% of Maine’s electricity generation. Solar panels on 500 acres or some of the planned offshore wind turbines could easily replace that power.

Fortunately, three small dams will soon be removed from Frost Gully Brook, near the highway in Freeport, a vital step for native brook trout that migrate between the ocean and fresh water. The Brunswick dam on the Androscoggin (and its barely functional fish ladder) comes up for license renewal in 2029. Dams need to come down so the healing can begin.

Ed Robinson’s latest book, “Nature Notes from Maine Vol. II: Puffins, Black Bears, Raccoons & More,” is available from the Harpswell Heritage Land Trust. All profits support HHLT’s conservation and education efforts.