Environmental groups wanted to remove a dam in R.I. They hit a wall of opposition.

The Potter Hill dam is the last remaining barrier on the main stem of the Pawcatuck River.

The old site of the Potter Hill dam and mill on the Westerly-Hopkinton border. Federal officials and environmental groups wanted to get rid of the dam, which one powered the mill, but locals balked and now the project is stalled.Courtesy of NOAA

WESTERLY, R.I. — The Potter Hill dam is not that big as far as dams go, but it has an outsize influence on the Pawcatuck River, which in turn has an outsize influence on southern New England’s ecosystem.

Some people want to see the dam removed, and have been working for two years to do it. But the town of Westerly is balking. On Monday night, the Town Council put up an obstacle by unanimously voting against the renewal of an engineering contract. The removal project is now, as the Westerly Sun put it, dead in the water.

The dam blockage has opened a rift between environmental advocates, who are concerned about climate resiliency, flood control and fish species like the river herring, and residents of Westerly and bordering Hopkinton, who worry about losing well water and waterfront real estate where they can launch kayaks or pontoon boats.

They do agree on one thing: Removing the dam would have brought significant changes to the Pawcatuck River.

“It’s just a huge missed opportunity,” said Tim Mooney, spokesman for the Nature Conservancy in Rhode Island, which had pledged funds to support the project.

Not so, said Sharon Ahern, the Westerly Town Council president. It is simply a pause to figure out the best way forward.

“I think it’s only a missed opportunity if you’re only interested in vastly increasing fish passage,” Ahern said.

Ahern also quibbles with the idea that the project was beneficial because it would bring the river back to its natural state.

“This is its natural state,” Ahern said. “We’re not going to go back to the days of dinosaurs and say, ‘Geez, this is the natural state.’”

There has, indeed, been a dam there for a long time — longer than there’s been a United States of America. It started as a grist mill in the mid-1700s, and over the years transitioned to a textile mill for wool and cashmere. In more recent years, it has had no practical use at all, and the mill that the Pawcatuck’s churning waters used to power is now falling into the river. The property itself is now under the control of a court-appointed special master.

Collapsing equipment on the site of the Potter Hill dam and mill on the Westerly-Hopkinton border. Federal officials and environmental groups wanted to get rid of the dam, which one powered the mill, but locals balked and now the project is stalled.Courtesy of NOAA

In 2020 the town of Westerly got a grant through the U.S. National Oceanic and Atmospheric Administration, with support from the Nature Conservancy and other partners, to explore removing it. It probably would have cost around $1.7 million. Five other dams on the Pawcatuck, which flows from inland headwaters to the Atlantic Ocean, have either been removed or repaired to allow fish to flow more freely.

The Potter Hill dam is the last remaining barrier on the main stem of the Pawcatuck. That’s why Monday night’s vote to do nothing about it is all the more discouraging, supporters of removal said.

“A dammed river is like a person having a bad heart problem, where the doctor has taken out five blood clots, and you have one blood clot left,” said Jim Turek, a restoration ecologist with NOAA. “You remove it, and you restore the person’s health. It’s the same condition with the Pawcatuck.”

Dam removals aren’t uncommon, although New England in general and Rhode Island in particular are behind other parts of the country in getting rid of these vestiges of a bygone industrial era.

This project, Turek said, would help the people in the area by allowing floodplains and wetlands to be restored. It would also help migratory fish like the river herring get from the ocean to fresh water upstream. Those fish play a major role in the ecosystem, and threats to their population would have consequences up and down the aquatic food chain.

The dam has a fish ladder now, but it doesn’t work nearly as well as a naturally flowing river would.

The old Potter Hill dam and mill on the Westerly-Hopkinton border. Federal officials and environmental groups wanted to get rid of the dam, which one powered the mill, but locals balked and now the project is stalled.Courtesy of NOAA

The town of Westerly’s administration was initially on board with the removal plan. But opposition started to rise at public hearings. Last year the Westerly town manager left his job, and members of the council said they learned more about the project when he left. They were baffled. And as neighbors took reporters and council members out on pontoon boat tours to illustrate their concerns, support for the plan eroded.

By removing the dam, the river leading to the dam would narrow. Residents worried the areas that were once pristine places to paddle a kayak or power a pontoon would transform into a mire of stinky mud.

They also raised concerns about shallow wells drying up.

“I think everybody would like to see better access for the migratory fish in the river,” Peter Ogle, a Westerly resident who came to oppose the dam removal, said in an interview. “But there are a lot of ways to upgrade the fish access without totally disrupting the local neighborhood and their wells and their boating access to the river.”

Environmental groups say those concerns are inflated or simply baseless. Yes, the river would narrow if the dam was removed, but the sides would not turn into desolate mud flats. They would turn into a lush, flood-resilient natural buffer. No, property values would not decline: removing dams helps property values. Anybody whose wells were affected would get government help to drill new, deeper ones. And the real safety risk is the dam itself, not removing the dam.

Wildlife experts were “gnawing their knuckles” at recent public meetings as opponents said the project would harm the environment, said Chris Fox, the executive director of the Wood Pawcatuck Watershed Association.

“The wildlife wants you to put the river back in its original condition,” Fox said. “That’s what they thrive in, not the manmade pond that was made a couple hundred years ago.”

The risk of dam failure is yet another contentious topic: The Rhode Island Department of Environmental Management lists the dam is low-risk, but that doesn’t mean it’s no-risk, supporters of removing it say.

“That raceway is ultimately going to fail,” said Turek, the NOAA official. “It’s wicked leaky right now and needs to be assessed.”

The Town Council came around to supporting an alternative proposal to removal: replacing it with what amounts to a system of smaller, more gradual impediments. That would help fish flow more freely. (Not freely enough; in fact, it could make migratory fish vulnerable to predators, the anti-dammers say.) This option would also not drastically change water levels upstream.

But the town backed away from that option, too. They might not have been able to get permits for it without support from NOAA and other partners. More to the point, they might not have been able to get the money for this more-expensive option if it wouldn’t actually help fish species and flood resiliency.

Ahern, the Town Council president, says it’s not the end of the story of the Potter Hill dam: They are simply going back to the well to figure out what to do next, including the old mill building. But it now won’t involve the removal of the dam.

“A lot of the residents have been physically sick over this,” Ahern said.