Just east of downtown Machias, Route 1 passes over the structure known as the dike-bridge. It's a scenic spot, with the Machias River estuary to the south, and the Middle River to the north. For the last 150 years the dike has prevented tides from flowing up into the Middle River. But the structure has deteriorated, and locals are divided over the plan to replace it with a new bridge.
The key components of the dike-bridge are four culverts that allow water to flow south from the Middle River, into the estuary, and gates, or clapper valves, that prevent tidal water from rushing in.
This story is part of our series "Climate Driven: A deep dive into Maine's response, one county at a time."
The design allows the land above the dike to be used for pasture and hay production. And as he stands on the dike and looks upstream, Charlie Foster of the Downeast Salmon Federation sees meadow where there was once salt marsh, and fish habitat.
“It’s become great habitat for deer and other animals," Foster says, "but the Atlantic salmon, who are critically endangered, and other fish species that use this river can no longer make it into the system, for the most part.”
The Maine Department of Transportation had been leaning toward a plan to repair the dike and enlarge the culverts. But under pressure from federal fisheries regulators, the department announced in June that its preferred alternative is to replace the dike with a bridge
That, Foster says, would allow alewives, smelt, striped bass and Atlantic salmon to swim freely into the Middle River. And it would create a rare opportunity to restore natural salt marsh habitat — and sequester carbon.
"In the Middle River, we estimated over a meter of peat loss over the past century, which would translate into a very large source of carbon into the atmosphere that didn't exist before," he says. "So now, with the conversion back to a salt marsh, you could turn that carbon source into an actual carbon sink."
But not everyone wants to see the salt marsh return. From here on the dike-bridge, you can see a tall pole erected in the riverside mud, topped with a flag that reads "Don’t Tread on Me."
“I was upset," says Chris Sprague. "And so what I put up was a Liberty Pole.”
Sprague says the Liberty Pole is a symbol that Machias settlers used to defy the British. Now he's opposing the bridge plan with the same fervor.
Sprague’s house sits on 90 acres just upstream of the dike. He says the original impetus for the structure was to create better farm land.
“And they figured it would be easier to hay this if they did that main dike system across.”
Walking along a path he maintains through a meadow, Sprague says it would look quite different if DOT builds a bridge.
“High tide, we’d be about waist-deep right here,” he says.
Sprague thinks it would make sense to repair the dike and the tide gates, which are starting to fail and no longer keep all of the tidal water out. He also fears that reopening the marsh will release contamination from an upstream dump.
But most agree that something has to be done.
“That dike will be removed by a storm if we don’t remove it soon, or change it drastically,” says Tora Johnson.
Johnson chairs the Division of Environmental and Biological sciences at the University of Maine at Machias.
She has been watching the dike for years, and mapping local sea-level rise. And she witnessed firsthand the effects of a major storm in April of 2020.
“I went down there in the middle of the night to see it," she says. "The Department of Transportation actually had folks on the dike, because they were concerned that the dike itself would be destroyed. And what I witnessed was water flowing over the dike into the Middle River above it, and waves crashing on it.”
The next day, Johnson saw that the dike had nearly been breached. She says such extreme events are becoming more common with climate change.
“Floods that are supposed to happen on average once every 100 years — we’ve had four of those in six years," Johnson says.
Advocates of the bridge option say it would protect Route 1 from the impacts of climate change.
But doubters, including Chris Sprague, say they don’t see an imminent threat in the area.
“To me, the theory behind the sea level rising, I don't really buy that," Sprague says. "To me, if that’s true, people wouldn’t be buying shorefront property in Florida and things, they would be selling it. To me, if it’s true that the sea level is rising, well, here’s a dike system, let’s help hold it back much like the dikes in Holland.”
And in the middle of the debate are local officials like Machias town manager Bill Kitchen.
“My job as town manager is to make sure that all of our people are heard," Kitchen says. "That if there are going to be affected landowners, that they are going to be compensated."
But Kitchen says whatever plan is chosen, he hopes the design will create a vibrant hub, perhaps incorporating a fishing pier, and even an amphitheater.
“It has the opportunity to be far more than a 1,000-foot-long two-lane piece of infrastructure to get you from point A to point B," he says. "It has the opportunity to have tremendous impact on both the cultural and economic development of a rural hub in Washington County.”
Whatever the final design, It will be expensive. DOT estimates that fixing the dike and culverts would cost up to $22 million, and building a bridge as much as $30 million.
Just a short walk from the town office, water is flushing from the Middle River under Route 1, and out through the clapper valves into the low tide of the Machias River estuary, as they have since the Civil War era. But this will soon change. DOT hopes to begin building the bridge by 2026.