Indigenous salmon could make full comeback in iconic Maine lake after dam removal

It came down to finding the balance between a piece of state history and a unique indigenous strain of fish.

Sebago Lake, surrounded by the towns of Casco, Naples, Raymond, Sebago, Standish and Windham, is one of four lakes in Maine that had indigenous wild strains of Atlantic salmon . Now it has the largest and most robust population, and possibly the only nearly self-sustaining one of the four.

The salmon, scientific name Salmo salar sebago, rely on the rivers that run into it for spawning grounds. One of the major tributaries, the Crooked River, until recently had a 200-plus-year-old dam on it, but it also represents more than 80 percent of the Sebago salmon’s spawning grounds. Some of the native brook trout spawn there too.

The Edes Falls dam, built in the late 1700s to power grist and saw mills, has been deteriorating for decades. Several courses of stone in the center of the dam were removed in 1972, allowing salmon to reach their spawning grounds when the water levels were high enough in the Crooked River. At low water, the fish were stuck behind the dam.

Climate change, characterized by lower and warmer water, forced state biologists and other conservationists to look into threats to the native salmon and brook trout’s ability to reach their spawning grounds. A big impediment was the Edes Falls dam.

But the indigenous salmon have evolved from 20 percent to 25 percent wild population in the 1980s to 70 percent to 80 percent in the last 30 years. Scientists believe the state-stocked and wild Sebago salmon strains are, for the most part, remaining separate populations that live and spawn in different areas of the watershed.

The ultimate goal is for the fish to be a self-sustaining,100 percent wild strain of Sebago salmon.

“It’s a big success story. It has taken generations of biologists to get this far,” said James Pellerin, Sebago fisheries biologist for the state. “We had to take a proactive approach to prevent failure [of the fishery].”

How the salmon got into trouble

It was common to catch 30-pound salmon from Sebago Lake in the late 1800s, which attracted the summer sporting crowd. They came year after year and killed what they caught, depleting the fishery, Pellerin said.

The state began stocking the lake by the 1930s with a hatchery-raised strain of the Sebago salmon, he said.

The strain was almost wiped out in the 1960s when spraying the pesticide DDT was popular, but the salmon slowly began to rebuild in the late 1960s and early 1970s, he said. When scientists figured out the salmon’s connection to the Crooked River, the Edes Falls dam was breached in 1972. That meant the salmon could get upriver if the water was high enough at the dam breach.

Most years, the fish were getting through, although the sluiceway often became clogged with stumps and trees that had to be removed, he said. The dam lost three or four more courses of blocks in the 1980s through natural deterioration, making it even easier for the fish to get through.

Scientists netted fish that were stacked below the dam and transported them into the headwaters to reestablish their homing instinct to spawn there. They also put some in small streams that hadn’t seen salmon in 200 years.

The state at one time stocked 12,000 fish and now it’s between 1,500 and 2,000, Pellerin said.

But the Edes Falls dam was in the way of more progress in the state’s efforts to restore the Sebago watershed fishery.

“It was time to finish the job we started in the 1970s,” Pellerin said.

The dam

People from the Maine Department of Inland Fisheries & Wildlife and Sebago Chapter of Trout Unlimited approached the Naples Board of Selectmen in 2019 about taking the crumbling dam out of the river.

The state said the water level would change only two feet and nothing would occur to the area beyond 300 feet upriver from the dam, select board member Colin Brackett said.

The town has owned the dam since the 1930s because the private owner stopped paying taxes, said Jim Wescott of Sebago Chapter of Trout Unlimited.

The board took the proposal through the public hearing process and appointed a committee of 12-15 people made up largely of Crooked River area residents and Brackett to discuss potential issues people had raised.

Some of the issues were fear that dug wells, river water levels and property values of the approximately 30 camps and year-round residences would be too adversely affected. There also were concerns about freer access to the river for invasive species such as pike and bass.

But the biggest issue was the historical significance of the dam.

There are still descendants of Robert Edes, for whom Edes Falls was named, living in Naples who see the dam as a memorial to their ancestors, Wescott said. One family member suggested the dam be rebuilt.

The select board-appointed committee of residents recommended removing two thirds of the dam, leaving the remainder as a nod to its historical significance. The select board agreed on June 14, 2022.

The violent rain and wind storms in May 2023 moved some of the key blocks in the dam, making them unstable and causing town leadership concern over public safety.

By the end of June 2023, the board declared a state of emergency and asked Sebago Chapter of Trout Unlimited and the MDIF&W to remove the remainder of the dam, leaving just the remnant on the west bank. The storms in December 2023 and January 2024 sealed its fate.

Some townspeople were vehemently opposed, but the decision was out of their hands.

Getting it done

With the majority of the funding coming from the federal Natural Resources Conservation Service, Sebago Chapter of Trout Unlimited, Lakes Environmental Association and Sebago Clean Waters, among other sources, the town of Naples did not have to foot the bill to have the dam removed. The total cost of the project could not be obtained Friday.

Other groups involved were Casco Bay Estuary Partnership, Maine Department of Inland Fisheries and Wildlife, Maine Council of Trout Unlimited, Sebago Lake Anglers, Sebago Rotary, The Nature Conservancy and U.S. Fish and Wildlife Service.

Site surveys and tagging trees for removal along the river brought out more interest from residents, said Jason Rogers, who has been town manager for eight months. There wasn’t much time from when the permits were issued to when a couple of the larger trees had to be removed because they were trying to beat nesting long-eared bats, he said.

Construction trucks were on the site just two days after permits were issued, Rogers said. The whole thing was done and cleaned up by June 19.

The speed with which the final process happened really bothered residents, he said.

“As town manager, I probably could have been more persistent with communication to the public after the decision was made,” he said.

The next chapter

Money for the Naples Historical Society to maintain the dam remnant was added to the project’s budget, according to Matt Streeter from Sebago Trout Unlimited. The society may decide how to spend the funds as long as it has to do with the Edes Dam site and provides public access and education.

Displays will include a history of the dam and the park will have walking trails and granite markers, Brackett said.

Some Naples residents are still angry about the removal of such a large portion of the dam, he said. This group doesn’t want the park improvements or any more work done to that area of Crooked River. They just want what remains to be left alone.

“Everyone wants to be heard. No one wants to be dismissed. If we can make reasonable changes, we want to do that,” he said.

Rogers hopes members of the community will play roles in revitalizing the park around the dam’s remains. He is reaching out to a landscape architect to design the park and will hold a meeting with the community in late July.

“It’s really a win-win,” Brackett said. “It didn’t cost the town anything. It would have cost the town a fortune to deal with the dam. And the river is back to its original state for the salmon.”

But the real winners are the fish.

The salmon are doing well in the lake and there are a lot of the fish in the 62-mile-long Crooked River, where it is fly fishing and catch and release only, Wescott said. Scientists are trying to track the fish through their life cycle to figure out where they live — the lake or a stream or river tributary — at each stage.

The salmon have some impressive hurdles yet. Although Crooked River’s faster moving water is not good habitat for invasive pike, that fish is becoming a problem in the Songo River, another Sebago tributary. Scientists are seeing scarring on salmon and trout coming from Songo that indicates injury from pike, Pellerin said.

But he doesn’t expect the same problems with pike in Crooked River. The habitat is wrong, he said.

“The greater mission [we have] is the restoration of the rivers and streams — removing the mechanizations put there by man to restore them to the wild,” Rogers said.