Westerly Town Council Decides Potter Hill Dam to Survive Mill Demolition
February 4, 2022
WESTERLY, R.I. — Members of the partnership planning the removal of the Potter Hill Dam and mill were surprised when Town Council members voted Jan. 31 to demolish the derelict mill but leave the dam alone.
Funded by an initial $100,000 grant from the National Oceanic and Atmospheric Administration (NOAA), the project, which originally included removing the dam as well as the mill, has also received more than $100,000 in in-kind donations.
The goal of the dam removal was to restore the river to its natural flow, which would in turn revive wetlands drowned by the water impoundment and allow migratory fish to swim freely up the river. Partners in the project, in addition to the Town Council, are the Westerly Conservation Commission, The Nature Conservancy, the U.S. Fish & Wildlife Service (USFWS), the U.S. Geological Survey, the Rhode Island Department of Environmental Management (RIDEM), the Southern Rhode Island Conservation District, the Wood-Pawcatuck Watershed Association and the Rhode Island Saltwater Anglers Association.
Built in the 1780s, the Potter Hill Dam is the only remaining dam on the Pawcatuck River. The mill, which was recently the focus of a failed private redevelopment plan, continues to decay and crumble into the river. Both the dam and the mill are currently in receivership.
Less than a year ago, the dam removal seemed a certainty when state and municipal officials and residents attending a public information meeting were presented with several options for its removal.
At that meeting, the town’s director of public services, Lisa Pellegrini, described the site as “a big, expensive problem” which, in addition to posing a public safety hazard, put the town at an increased risk for flooding.
“If the dam fails, there will be a devastating flood that will greatly affect Westerly,” she said.
However, the Town Council had more recently backed away from the dam’s total removal and proposed that rather than remove the dam, another plan, known as “Alternative 3,” would involve the removal of some of the dam and improvements to the fishway.
Then, at a Jan. 31 Town Council workshop, there was another change. Council President Sharon Ahern told members that when she and other town representatives attended a preapplication meeting in December, it was evident that Alternative 3 would not be acceptable to NOAA, the principal funder.
“It just wasn’t going to be possible, because the parameters of the grant are very clear that they want, basically substantially increased, I think it’s fair to say, fish passage, and that is really not what Alternative 3 does,” she said.
Fuss & O’Neill water resources engineer Nils Wiberg proposed a fourth alternative that would involve lowering the water level incrementally to determine the impacts of progressively lower levels, but the council declined to explore that option, instead voting not to renew the Fuss & O’Neill contract, effectively killing the dam removal project.
A major factor contributing to the council’s decision was the belief, shared by all six members, that the dam could safely remain in place.
Council member Karen Cioffi said she did not believe the dam was at risk of failing.
“I’m a lot of things, a skeptic for sure, not an engineer, yet I’m able to read here that RIDEM says that their dam safety committee says that dam is currently characterized as a low hazard,” she said.
Other council members agreed.
“I don’t want to talk about it anymore. I’m done,” Caswell Cooke said. “I want to get the mill down, and then we’ll talk about the dam.”
But the condition of the dam is largely unknown. RIDEM spokesperson Michael Healey said low-hazard dams are given visual inspections only, and the most recent of those visual inspections, which included the Potter Hill Dam, were done in 2005.
“We do not inspect low-hazard dams because by definition, low-hazard dams pose no threat to life and only a minimum threat to property,” he said. “These are visual inspections that do not involve full engineering analyses of the structural integrity of dams. We do not have the staff or financial resources to conduct full engineering analyses of all 669 inventoried dams in the state.”
Wiberg confirmed that there has never been an assessment of the structural integrity of the Potter Hill Dam.
“They have never conducted a hydraulic analysis to confirm that is a low-hazard dam,” he said. “They simply determined in the ’90s or early 2000s that it is a low-hazard dam and they have not determined that a refined analysis is warranted to determine that it remains a low-hazard dam.”
There is an important distinction to be made between the dam’s low-hazard state classification and its actual condition, which, in the case of Potter Hill, is not good.
“There is no functional low level outlet structure,” Wiberg said. “As a result, if an inspection of that dam were to be conducted, my understanding is that it would be classified as an unsafe dam. … The timber gates on the left side of the dam that are leaking right now and are continuing to deteriorate, cannot be operated. There’s no operable valve or gate that can lower the water.”
NOAA restoration ecologist James Turek said it was a mistake to assume that the dam does not pose a hazard.
“It’s a great deficiency, in my opinion, that people are equating low-hazard dam classification to ‘there is no significant potential problems with that dam,’” he said. “It would be foolish. That is not correct. It’s a terrible assumption and I would highly recommend that the town should complete a dam assessment to understand the deficiencies that may exist.”
As much as the dam removal was supported by environmental groups, riverfront property owners hated the proposal and lobbied vociferously against it, because lower water levels would have impacted riverfront properties, including wells, in both Westerly and Hopkinton. Rep. Brian Patrick Kennedy, D-Hopkinton, who represents the district, said residents had told him they felt the dam removal was being “rammed through” by environmental groups without consideration of their concerns.
“These other organizations that were helping to supply the grant money did not want to hear from local people,” he said. “It really is outrageous that these organizations that deal with environmental issues don’t want to hear what anybody has to say.”
Kennedy said residents would oppose any lowering of the water level.
“Trying to maintain it as much as we can so that the water level stays where it’s at and not make a big change because ultimately, and especially in the town of Hopkinton, which doesn’t have a lot of waterfront property, this is waterfront property and those people actually, in their assessment, pay higher taxes to have waterfront property, as opposed to wetlands property where they don’t really get an access to the river,” he said.
Further complicating matters is the issue of whether the town will assume ownership of the mill property, which is in receivership.
Court-appointed special master John Dorsey told the council last month that the demolition of the mill might still necessitate the removal of the dam, because the $400,000 for the demolition will be coming from the federal American Rescue Plan Act.
“Because it’s federal funding, it would trigger something called a Section 106 review which is a historical review,” he said. “That’s usually delegated to the state historic agency on behalf of the federal government. We did have prior site visit with State Historic [the Rhode Island Historical Preservation & Heritage Commission] to the mill building to explain the project, explain the different issues that we’re looking at, trying to get some initial feedback. … The feedback that I got was that State Historic would like to try and do this project as one.”
Turek said federal permits would require addressing the dam, because it would be impacted by the demolition of the mill. “I don’t believe they can possibly say, ‘We’re only going to touch the building and we’re not going to touch the dam or its components associated with it.’”
Westerly will now refund about $100,000 to NOAA and more than $20,000 to USFWS. The disposition of the mill property and the requirements of federal funding, which may include the removal of the dam, are still to be determined. Turek said his agency would have been willing to work with the town to explore Alternative 3.
“The partners were never saying, ‘We’re drawing a line in the sand. If you don’t take the dam out, we’re walking.’ No one ever said that. There’s been interpretations suggesting that and we also never said we wouldn’t do Alternative 3,” he said.
The Nature Conservancy, which has contributed $112,500 to the project for engineering studies, would also have been open to finding a way to continue the project.
“Even though we didn’t agree with the alternative that the council was pursuing, we were still willing to continue and provide technical expertise and figure out is there a way to satisfy upstream interests and achieve the goal of the grant and the project at the same time,” Conservancy communications manager Tim Mooney said. “We all expressed willingness to pursue that.”