With two out of three drainage pipes installed, the Town of Rhinebeck is managing to keep water issues at a capped landfill under control.
The 8.5-acre property is located on Stone Church Road near the Olde Rhinebeck Aerodrome. It was opened in the 1950s and closed in 1997.
The problems were detected at least as early as September 2012, when consistent flooding prompted the state’s Department of Environmental Conservation to recommend mitigation.
“Their real concern is that we lower the water level sufficiently so that the closed landfill is not compromised,” Bruce Washburn, the town board liaison for the project, told The Observer. At the time, a water level rise of as much as two to three feet was detected.
One concern is that the runoff from the water may be carrying chemicals away from the landfill and into the water table. “It’s also in the middle of two DEC wetlands. It was that old school 1950s [mindset], ‘Hey, it’s wet, no one’s going to build there, let’s throw all the garbage in there,” Jeff Romano, chair of the Town of Rhinebeck Conservation Advisory Board, said.
A beaver dam is one source of the most recent drainage problem. The two installed pipes run through the existing dam, protected by metal mesh to keep away the beavers—who are notorious for plugging any perceived leaks in their dams—and allow water to flow through to where it can drain away.
“The two pipes that we installed are keeping the water table down so that flooding is less than in September of 2012. We have another pipe to go in the fall, after the growing season. Our hope is that the third pipe will further lower the water level so that monitoring wells for the landfill are not compromised,” Washburn said.
“If you look at the wetland, it looks like a tooth with the roots and we found a way in between the roots, so we could get in without disturbing anything,” Washburn told CAB members at their July 1 meeting. “Our concerns are that if we take the main channel dam out too quickly, we flood the aerodrome. If we take it down just a little bit at a time, the beaver will rebuild every night, so we’ll never make any headway. So, [when we insert the third pipe] we have to do it very quickly: rip it out, stick in the pipe, that kind of an operation.”
In response, Romano praised the town board’s decisions so far. “[CAB] is advocating for a long-term solution to this, rather than raise the level of the road that goes back there or chasing the beavers away, because [the water] is just going to keep coming. To the credit of the town board, rather than just kill the beaver, which was the initial idea, they listened to the advice of the experts and their advice was, ‘No, the beaver are just going to come back, we can’t kill all the beaver in New York state,’” he said.
Washburn and Romano recently inspected the site and found that the water was staying at about 18 inches below what it had been last September, even with all the rain this summer.
According to Washburn, the town’s buildings and grounds department has handled the construction and installation of the pipes, also known as pond levelers, with guidance from town engineer Tom Mannix. The total cost for the project will be close to the $3,000 previously estimated by the board.
Washburn said that analysis by The Chazen Companies, an engineering firm specializing in environmental and land issues, indicated that the landfill works adequately when the water table is low. “The problem is, when it’s a dry year, that landfill performs to spec. When it’s a wet year, it doesn’t, going back to when it was closed,” he said.
However, Romano pointed out at the July 1 meeting that the beaver dam may only be part of the problem and more work will need to be done to find a long-term solution. “The DEC report said that really, the beaver may not be our problem. A hydrology study needs to be done to find out if the water is coming up underneath, or whether it’s because of damming. We don’t know where the water is coming from.”
Washburn said the town board plans to do the hydrology study after the third pipe is installed.