CHESTER — After this week’s flooding caused significant erosion to earth around the Chester Reservoir dam, town officials expressed concern that more rain this week could prompt the dam to fail, leading to even more significant flooding.
“It’s a concern, but it’s not a high-level concern where we would evacuate people at this time,” Julie Hance, Chester town manager, said Wednesday afternoon. “It’s something that we’re watching, and we’re watching closely.”
Torrential rains this week caused the Chester Reservoir to overflow, eroding earth around the dam as spillover water flowed toward the Williams River, Hance said. If rain in the forecast causes the dam to again overflow, it could destroy the structure, she suggested.
Around 4 p.m. on Wednesday, the water level of the dam was about 6 to 8 inches below maximum capacity, Hance said, though runoff from the mountains continued to enter the reservoir. Chester had contacted the State Emergency Operations Center to request pumps that would transfer water in a controlled fashion from the reservoir into the spillway, according to the town manager.
If the dam failed, Hance said, the water would take out Reservoir Road and parts of Route 11 West. But she stressed that the dam is currently stable.
At the dam on Thursday around 4 p.m., the extent of the damage was apparent. Craters of flood-moved earth were still wet to the touch behind the dam’s concrete. Brown water continued to flow out of the reservoir into a spillway.
No special equipment was being used to more quickly remove water, and at that time, no one was on the scene.
According to the state Agency of Natural Resource’s dams inventory, the Upper Chester Reservoir Dam has been labeled in “poor” condition since at least 2006. The state lists the dam’s hazard potential as “significant.”
This week’s storm caused significant flooding and damage in Chester, where multiple bridges along Route 103 over the Williams River had become impassable and roads suffered major damage. The town also had two water main breaks, which, like elsewhere in the state, had spurred boil water orders, according to Hance, though that order ended Thursday.
According to Stephanie Brackin, a spokesperson for the state Agency of Natural Resources, the town of Chester owns two dams at its reservoirs.
The state agency “plays an ownership role” at about 100 dams in Vermont, and there are about 1,000 dams total in the state, Brackin said.
As of Thursday, Brackin said dam staff “hope to go out and take a peek” at the Chester dam. But, she said, “The Wrightsville and the Waterbury dams are our primary focus.”
In the meantime, “The town can work with their local emergency management officials,” Brackin said.
At a press conference with Gov. Phil Scott on Thursday, Maggie Gendron, deputy secretary of the Agency of Natural Resources, said, “It’s the responsibility of private dam owners to monitor their dams and report out to emergency management if there are any issues.”
Gendron also said the state had “completed outreach” to owners of municipal and private dams across the state, and wasn’t aware of any problems.
Chester, like the rest of Vermont, was under a severe thunderstorm watch on Thursday. The town manager did not return an email and phone message with further questions about the dam.
