For years, local officials have sought to remove the Hands Mill Dam, a decades-old concrete structure on the Jail Branch, a tributary of the Winooski River, in the town of Washington.
The structure was in poor condition and was classified as a “significant” hazard, meaning it could cause “major or extensive” property losses if it failed, according to state officials. Conservationists also wanted to restore the river’s natural ecosystem.
After years of work to secure funding, find a contractor and design a deconstruction strategy, officials planned to remove the dam next summer.
Earlier this month, historic flooding beat them to it.
On July 10, floodwaters smashed through the concrete dam. The deluge downed trees, destroyed a shed and camper and washed massive quantities of sediment into the Winooski — until, some officials believe, it ended up coating the streets of downtown Barre.
“Unfortunately, what happened with it was exactly what we were trying to prevent,” said Sheila Duranleau, the chair of the Washington Selectboard.
The massive flooding that struck Vermont earlier this month put a spotlight on the state’s network of dams, hundreds of which block rivers and hold back reservoirs.
As rain fell and rivers rose earlier this month, Vermonters watched anxiously as water filled up large reservoirs and strained dams. Officials said most dams functioned exactly as designed. But many are known to be in poor condition, and some sustained damage from the flooding — with at least a handful of small structures failing completely amid the deluge.
“This event has definitely called into question our dams, and what state they’re in, and the safety of them,” said Karina Dailey, a restoration ecologist with the Vermont Natural Resources Council who heads the organization’s dam removal efforts.
‘Vermont has been lucky’
As Europeans settled across the northeast, towns and homes sprung up largely along waterways. Damming rivers allowed residents to store water, power mills, and harvest ice.
It’s not clear exactly how many dams are in Vermont, but experts believe the number is over 1,000. They range from large flood control dams to hydroelectric plants to small, antiquated structures on private property. The oldest is about 230 years old, and the average age is roughly 80 years.
In Vermont, dam oversight is a patchwork system. The state Department of Environmental Conservation’s Dam Safety Program oversees just over 400 dams in the state. Dozens more are administered by federal agencies, and about 20 hydroelectric dams are overseen by Vermont’s Public Utility Commission.
In February, the state’s chapter of the American Society of Civil Engineers gave Vermont’s network of dams a “C” grade. Roughly a third of the dams overseen by the Dam Safety Program are classified in “poor condition,” according to the group’s report. Many are now abandoned and deteriorating.
“With many dams in poor condition and the recent increase in larger and more intense floods, the risk of dam failure is increasing,” the report reads. “Vermont has been lucky to not have had a recent complete dam failure leading to loss of life and damages.”
Last year, a report by the state auditor’s office found holes in the state’s oversight process. The Dam Safety Program was understaffed, failed to provide dam owners with inspection reports, and was unable to force owners to make repairs to dams in poor condition, auditors found.
“As a result, some of the dams we reviewed have lingered in poor condition for at least 18 years,” the auditors’ report reads.
Lawmakers granted Dam Safety officials more oversight powers in 2018, and the program is currently in the process of strengthening its requirements for dam inspections, said Neil Kamman, the director of the Department of Environmental Conservation’s Water Investment Division. Those new rules will allow officials to compel landowners to make improvements, as opposed to simply recommending them.
Auditors also pointed out discrepancies in state oversight: two state entities — the Dam Safety Program and the Public Utility Commission — had different inspection schedules and guidelines: while the Dam Safety Program inspects some dams every other year, the Public Utilities Commission only does so at most once every five years.
Officials at both the Dam Safety Program and the Public Utility Commission said that discussions about consolidation are ongoing, and they expressed no opposition to such a reorganization.
But such a move would require action from lawmakers, Kamman said.
“That’s not a short conversation,” he said. “And that’s not, kind of, a thing that can be simply one and done.”
‘They truly did their job’
Vermont’s large, crucial dams held strong during this month’s storm, officials said.
The state’s large Winooski River flood control dams in Waterbury, Wrightsville and East Barre “functioned magnificently to protect central Vermont — to protect Barre, Montpelier and Waterbury — from what would have been much, much worse flooding,” said Kamman. “They truly did their job.”
Kristin Carlson, a spokesperson for Green Mountain Power, which owns 40 dams in Vermont, said that the utility took steps to prepare prior to the floods, such as lowering water levels in reservoirs.
“All of the dams that we own and operate worked exactly as designed during this historic event,” she said.
But for many Vermonters, rising water levels made for a nail-bitingly anxious time. In the Wrightsville Reservoir, water rose to within a foot of its spillway, threatening to exacerbate the damage in already-flooded Montpelier. Ultimately, the reservoir did not reach the spillway, but state officials said that between three and four more inches of rainfall could have brought water pouring over the top.
“In the context of what had happened over Sunday night to Monday, you know, that’s not a lot,” Kamman said. He said the state plans to study ways to improve the dam’s drainage to avoid danger during another heavy rainstorm.
In Chester, water overflowed the Chester Reservoir dam and eroded its sides, raising fears — ultimately unrealized — that it would fail. After the flooding, officials in Williamstown also expressed anxiety that a privately owned dam could breach, sending floodwaters into town, according to the Times Argus.
After water receded, state inspectors fanned out to examine the conditions of more than 350 dams in Vermont. Inspectors found defects in at least 60 dams, which “one could presume” occurred amid the floods, according to Kamman.
Five of those dams were classified as “high” hazard, which means a “probable or certain” loss of life downstream in case of failure. Twenty-two were “significant” hazards — like the Hands Mill Dam — meaning failure could cause “major or extensive” property loss.
John Schmeltzer, the deputy commissioner of the Department of Environmental Conservation, said in an email that none of those 27 dams are “at risk of imminent failure.”
But at least three small dams failed completely during the flooding: the Hands Mill Dam, the Clark Sawmill Dam in Cabot, and the Lyons Dam in Peru, according to state officials. No injuries were reported, and it’s not clear how much damage, if any, the failure of those dams caused downstream.
‘Tons of permits’
Removing small dams is one strategy to mitigate the threat of floods, but the process is long and complicated. Dam removal requires the landowner’s permission, which can be tricky: Most small dams are owned by private landowners, and many are under uncertain ownership or abandoned.
Once a landowner consents to the removal, the process requires multiple rounds of funding — for feasibility studies, designs, and the actual excavation.
“They have to get tons of permits,” said Michele Braun, the executive director of the Friends of the Winooski River. “You need a stream alteration permit, or if it’s a bigger dam, you need a dam order from the dam safety division. We have to go through historic preservation review. Lots, lots of regulatory review.”
State and conservation officials said that dams are removed at the pace of roughly five a year. At that rate, it will take decades to free up Vermont’s rivers — decades in which decrepit dams continue to deteriorate, or fall apart on their own.
In Cabot, as well as in Washington, local officials hoped to remove the dams that were destroyed. In Washington, town officials recently purchased property just downstream of the Hands Mill Dam, which held an uninhabited, dilapidated house and sheds and campers. The town planned to demolish them as part of the dam removal.
The floods got there first: A video circulating on social media shows floodwaters from the broken dam picking up a shed and camper from the property and ramming them against the underside of a low bridge just downstream. A neighboring property owner has been finding pieces in his fields, said Harry Roush, Washington’s assistant town clerk and moderator.
On Tuesday, roughly two weeks after the flooding, Roush showed a reporter the state of the Jail Branch. The water had carved the tributary into a canyon and hurled chunks of concrete from the dam downstream, toppling trees and rerouting the flow of the water.
Prior to the flooding, the Jail Branch was relatively calm in Washington. “In the summertime, in a normal year, you might get your ankles wet,” Roush said. “There’s enough water there to support a little brook trout life.”
Engineers estimated that the dam was holding back roughly 14,000 cubic yards of sediment before it was breached. Both Roush and Casey Spencer, a district manager at the Winooski Natural Resources Conservation District who, until this month, was overseeing the dam’s removal, believe that much of that sediment was carried all the way into downtown Barre, likely contributing to the thick, noxious mud that made that city’s flooding so devastating.
“The logic is — yeah, that’s how it flows,” Spencer said. “So this is upstream of Barre.”
So now what? Officials said they are still waiting for information from engineers about what will happen next to what remains of the dam. Some pieces of the structure remain standing, but plans for removal, if still necessary, will need to be completely redesigned.
“There were plans to alter the stream,” said Spencer. “It did it for us. It picked its own path.”
