Credit: Photo: K.D. Lawson / Black Star
Standing in front of the beaver dam they worked so hard to keep, Ellen Smith (left), Josh Collins, and Gary Cinder (front), agree that this project has added to the community. For example, Boy Scouts have built a nature trail to the dam from an accessible area of the park.
Oak Ridge, Tenn., was faced with a rather unusual problem. Beavers had built a dam in a designated wetland area adjacent to a city-owned park, and residents had some concerns over the standing water and the beavers. The beaver dam was environmentally useful because it retained the water level in the wetland area, but citizens were still troubled by the pond.
“Several Oak Ridgers voiced concern over the presence of a beaver pond adjacent to a heavily used soccer field and a major roadway,” said Josh Collins, director of recreation and parks with the city of Oak Ridge. “The community was divided over how to deal with the beavers.”
So the city council-appointed Environmental Quality Advisory Board (EQAB) was assigned responsibility for resolving the issue. The diverse board—an unbiased community resource—works together to research a topic and make recommendations. “Oak Ridge has an unusual concentration of scientists and engineers, so our membership sometimes includes a person with specialized technical expertise that can help the city solve unusual technical problems,” said Ellen Smith, chairperson of the EQAB in Oak Ridge.
The Oak Ridge EQAB deals with a host of city problems, from beaver dams to U.S. Environmental Protection Agency regulations to solid waste programs. “The city's EQAB serves as a resource to the city council, the planning commission, and the [public works] staff to review topics of environmental interest,” said Gary Cinder, P.E., public works director of Oak Ridge. “When we have a matter arise in our department that we believe needs further input, we bring it to EQAB for their assistance.”
The beaver dam became a big issue about 10 years ago, and the board was called in to help resolve it. “One of our members works as a wetlands scientist,” said Smith. “He found out that before the beavers arrived, the site of the pond had been surveyed and determined to be a wetland. Thus, placement of fill to discourage the beavers would violate Section 404 of the Clean Water Act unless a permit was obtained from the Army Corps of Engineers. We shared this information with the city staff.”
Since the dam was constructed in a wetland area adjacent to a city-owned park, the EQAB worked with the Recreation and Parks Department to help solve the problem. Collins and his crew had to consult with the Army Corps of Engineers to determine what could be done to the dam, what regulations governed these activities, and what permits were required. Additional information from the Tennessee Valley Authority, the Tennessee Department of Environment and Conservation, and the U.S. Department of Agriculture (USDA) allowed the city to formulate a plan of action.
Community concerns were always an issue for the department. “We had to find a solution that would address the fears expressed by one segment of the population while retaining a natural attraction—the beavers and their dam— for the remaining residents,” said Collins. The USDA/Soil Conservation Service provided a solution for dealing with the beavers that brought a win-win solution to the table. “The idea of installing the Clemson Beaver Pond Leveler (developed at Clemson University in South Carolina) in the pond was well received by all the agencies involved,” he said.
The beaver dam was constructed at the base of a bank along a stream channel. The leveler was constructed using polyvinyl chloride pipe, wire, and welded fence fabric. “The Clemson Beaver Pond Leveler actually regulates the depth of the water in the pond and allows excess water to run through the dam to a standpipe on the downstream side of the dam,” said Collins. “Since beavers are attracted to the sound of running water, the piping system moves excess water quietly through the dam into the channel below. When the beavers no longer hear running water, they feel their dam is complete and they move on to other areas.”
“The public works department provided the heavy construction labor and equipment to install the leveler in the dam,” said Cinder. “Our challenges were doing such heavy construction in a protected wetland area with the project having a very high visibility within the community. The terrain was quite steep, making simply getting to the site challenging.”
The beavers remain in residence, although the leveler has been successful in keeping them from enlarging the pond. However, citizen concerns continue to arise, and city personnel and EQAB continue to work together to resolve those concerns. “Last year, we heard from citizens concerned about the risk of contracting disease from the mosquitoes,” said Collins. “We don't think that this pond provides the habitat needed by the mosquitoes that carry West Nile virus, and EQAB is helping gather information to confirm that.”
For information about the EQAB in Oak Ridge, Tenn., visit www.ci.oak-ridge.tn.us/eqab.