Beavers dam it, affected humans tear it out

by Bob Hansen

If only beavers would keep their dams away from places where people live and work, it’d be easy to ignore them. But the large furry rodents with flat tails are getting attention because they don’t know that.

The town of Hagerstown has removed two dams this year. A third will probably stay just outside of town. The county isn’t very worried about it.

Wayne County gets involved in two ways. At the Hagerstown site, next to the Steve Swoveland Nature Preserve, the Wayne County Highway Department is keeping an eye on the dam in case it starts damaging a nearby bridge. But if the dam was in a legal drain, the Wayne County Surveyor’s office could become involved, as it is north of Centerville.

Hagerstown’s Town Manager, Chris LaMar, says seven beavers are responsible for building the two dams torn out by the town. They have built a third where a county bridge carries Teetor Road across a channel of the Whitewater River, LaMar told the Town Council on March 6.

Wayne County Highway Supervisor Mike Sharp said the town told him of the dam since it is outside of town. But the beavers built the dam where county equipment can’t get to it.

Currently the dam isn’t hurting anything. Because it’s north of the bridge, the dam will only slow water flowing under the bridge. Had beavers dammed south of the bridge, the water would have ponded under it, possibly undermining the structure and the roadway, Sharp said.

“I get more concerned if it’s going to undermine a structure, causing hundreds of thousands of dollars in damage,” Sharp said. “We’ll keep an eye on that one and figure out what to do if it starts causing problems.”

Beavers build dams as a part of constructing their homes and to protect themselves from predators. In some cases the dams can help the surrounding ecosystem by reducing erosion and filtering water, but in others they can cause issues.

The county surveyor’s office gets involved when legal drains, often called ditches, become blocked. That includes removing beaver dams, said Rob Clark, the surveyor’s chief of party. Landowners along a legal drain pay a yearly assessment to keep the ditches clear of obstructions. Allowing water to back up can block farm drainage tiles and damage crops.

Both the Highway Department and the surveyor’s office are involved in clearing beaver dams that are affecting residents of an area north of Centerville. Clark said three or four beaver dams are in the Russell Ditch, a legal drain between the Warm Glow Candle shop and Gaar-Jackson Road.

The dams back the water into Dogtown, a low-lying area with several residences. It gets into septic systems and drinking water, sometimes flooding the houses. The surveyor’s office clears the dams from Russell Ditch.

The highway department tries to remove dams in or near highway rights of way, Sharp said. They’ve been removing dams at Dogtown for at least 20 years.

Clark said the surveyor’s office had cleared trees and brush from the O’Brien Ditch one year, giving beavers nothing to build with. The drain flows from Gaar-Jackson to Industrial road. The following year, a farmer planted corn. Beavers used corn stalks for construction, making more dams for the surveyor to remove.

The two county offices and the town of Hagerstown all said they don’t kill or harm the beavers.

But “when it causes problems, we try to do the right thing,” Sharp said. “But the beaver is doing it for their reasons too.”