DERRY — “Significant undermining” of Beaver Meadow dam forced emergency repairs to the structure off Sabra Circle and Martha Drive.
American Excavating crews began preliminary work yesterday after a resident called the town reporting an unusually high flow of water at the dam.
Beaver Meadow dam is at the southern end of Beaver Lake.
Public Works director Michael Fowler said town crews and state Department of Environmental Safety dam officials inspected the structure earlier this week for possible damage.
Residents living in the area are being advised to stay away from the dam. Buoys were placed on the pond to warn canoeists and kayakers not to approach.
With water flowing fast, Fowler said, sandbags were being deployed to ease some of the stress on the dam temporarily.
“We will then come up with a game plan,” he said.
A notice issued to residents yesterday said “the Beaver Meadow dam requires an immediate repair due to significant undermining of the dam structure.” The notice said the work would take about a week.
Fowler said it was unknown what caused the problem — It could have been something as simple as soil erosion producing a gap or more intense structural damage.
This dam dates back to the early 1900s and helps control water coming through town from Beaver Lake. Fowler said the dam’s style is referred to as “low structure and low hazard.”
“It’s definitely an older structure,” he said.
The town has several dams, many privately owned, that are inspected by the state periodically.
Although the structure appears to be safe, Fowler said, water was flowing under the dam at high velocity so people should play it safe and steer clear. It posed a particular hazard to children trying to cross the dam, he said.
“We want to get to this as soon as possible,” he said.
Fowler said dam repairs could cost $15,000 to $20,000 depending on the extent of the problem.
“By jumping on this as an emergency situation, hopefully it will keep the dam issue to a minimum,” he said. “This is the reason we need to be equipped for all emergencies.”