Maine has removed a 60-year-old river barrier on the Narraguagus River where only about 25 wild adult Atlantic salmon return each year, replacing it with a nature-like fishway designed to reopen migration routes for endangered fish.
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salmon → remove → fish
The old ice-control dam in Cherryfield, built by the US Army Corps of Engineers in 1961, long blocked salmon, shad and river herring from reaching upstream spawning grounds.
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dam → build → grounds
With construction underway since June and completion expected by November, the new stepped channel aims to restore connectivity while still protecting the town from ice jams and flooding, according to reporting by The Maine Monitor.
uncertain
channel → expect → Monitor
A river built for salmon, but short on fish
The Narraguagus runs about 40 miles from its source in the downeast lakes to its head-of-tide in Cherryfield.
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Narraguagus → build → Cherryfield
Along much of its length, the river and its tributaries are wild and largely undeveloped, with shaded stretches and rocky bottoms that biologists describe as prime Atlantic salmon habitat.
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biologists → shade → habitat
Yet for decades, the salmon have been missing.
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salmon → miss → decades
In recent years, only around 25 wild adult salmon have returned to the Narraguagus annually to spawn, a tiny fraction of the hundreds of thousands that once migrated through Maine’s rivers each spring.
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that → return → rivers
Gulf of Maine Atlantic salmon are listed as endangered under the federal Endangered Species Act.
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salmon → list → Act
Across the state, only about 1,000 adults come back from the sea each year.
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adults → come → sea
To move the population from endangered to threatened, Maine would need at least 1,500 wild adults returning each year for multiple years.
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Maine → move → years
Full delisting would require around 6,000 wild adults spread across different watersheds, with enough suitable habitat and a growing population.
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delisting → require → habitat
The US Army Corps of Engineers built it in 1961 to hold back ice jams that used to flood the town.
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that → build → town
It had a fish ladder on one side that alewives navigated relatively well, but many salmon and shad struggled to find or use it.
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salmon → have → it
Fisheries officials often saw adult salmon gathering below the dam, unable to pass.
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salmon → see → dam
Over time, inspections showed the structure was aging.
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structure → show → time
The town could not afford to repair or replace it on its own.
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town → afford → own
That opened the door for a coalition of conservation groups, including the Maine Coast Heritage Trust, the Downeast Salmon Federation, the Atlantic Salmon Federation and The Nature Conservancy, to propose a different solution.
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coalition → open → solution
They suggested replacing the dam with a nature-like fishway that would maintain ice and flood control while allowing fish to move more freely.
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fish → suggest → ice
From federal dam to community project
Before the replacement could begin, Cherryfield had to take ownership of the dam from the Army Corps.
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Cherryfield → begin → Corps
That required a town vote and an act of Congress.
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That → require → Congress
In a special meeting in 2023, residents voted unanimously to take over and then take down the dam.
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residents → vote → dam
Shortly afterward, Congress de
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Congress → de → ?
The project received $9.1 million from NOAA’s Restoration Center as part of the Bipartisan Infrastructure Law, and construction started in June 2026.
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construction → receive → June
The new design uses a series of stair-stepping pools that mimic a natural stream channel.
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that → use → channel
This nature-like fishway is intended to slow ice and reduce flood risk without creating the sharp drop and turbulence that blocked fish at the old dam.
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that → intend → dam
Alongside the river work, the project is also revamping a nearby park that was rarely used, adding bathrooms, an amphitheater, electricity and a floating dock requested by local children.
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that → revamp → children
Measuring success with shad DNA
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Measuring → measure → DNA
Scientists plan to measure the impact of the new fishway using shad as a proxy for salmon and other sea-run fish.
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Scientists → plan → salmon
Shad are more numerous than salmon in the Narraguagus but are also more sensitive to barriers, so their movement can signal how well the passage is working.
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passage → signal → barriers
Researchers are collecting water samples above and below the dam site and sending them to the University of Maine in Orono to test for shad DNA.
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Researchers → collect → DNA
Baseline samples taken in spring 2026, before the dam was removed, showed more shad DNA below the Cherryfield dam than above it.
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dam → take → it
The team will repeat the sampling next summer and hopes to see similar concentrations of shad DNA on both sides of the new fishway.
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team → repeat → fishway
If shad begin moving freely, it is a strong sign that salmon, river herring and other species will also benefit.
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salmon → begin → ?
Climate change and the limits of restoration
Even with the barrier gone, the future of Atlantic salmon in the Narraguagus is uncertain.
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future → go → Narraguagus
Maine sits at the southern edge of the species’ range, and the Narraguagus runs warm compared with more northern rivers.
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Narraguagus → sit → rivers
Atlantic salmon begin to experience stress when water temperatures rise above 68 degrees Fahrenheit, a threshold the river often exceeds in summer.
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river → begin → summer
As summers grow longer and hotter, that thermal stress is expected to increase.
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stress → grow → ?
Scientists have flown infrared cameras over the river to map temperature variations and identify the coolest stretches and tributaries.
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Scientists → fly → stretches
Early results suggest that while much of the main stem is warm, some tributaries remain cold enough to support salmon.
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tributaries → suggest → salmon
The new fishway should give more fish access to those refuges, but long-term survival will depend on how quickly the climate changes and whether the population remains large enough to adapt.
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population → give → refuges
…and 25 more, not listed.
The Aporia
