Released July 31, 2009
STILLWATER, Okla. – Keys to a good pond include keeping aquatic growth controlled, a healthy population of fish and a high quality of water. But landowners need to remember that there is another vital element: pond dams.
“We tend to focus on the water and the fishing but pond dams need our attention too,” said Marley Beem, Oklahoma State University Cooperative Extension aquaculture specialist. “Dams fail because people either don’t understand how they work or they just forget about them.”
A dam failure is at best expensive and at worst disastrous when roads, homes and other structures are in the path of the flood. To avoid these costly events, Beem offered a reminder of the three main enemies of pond dams that require attention. The first is burrowing animals, such as muskrats, beaver or pocket gophers.
“A gopher burrow may look minor but you need to take steps to eliminate the pest and properly fill the burrow as soon as it is noticed,” said Beem. “Even a small burrow is enough to get water flowing through the dam and it is all downhill from there.”
Furthermore, burrows can interconnect or be dug too close to each other, greatly weakening the structure.
The second threat to a dam is one about which many people have a misconception. Often, trees are believed to strengthen a dam, but the roots can become a serious threat.
“Tree roots loosen the compacted soil of the dam and provide pathways along which water can begin to move through the dam,” said Beem. “When a large tree dies or blows over, the roots decay, leaving a network of small tunnels that often lead to dam failure.”
The final of the three dam killers is erosion of the slopes, top or auxillary spillway. These areas should be refilled with compacted soil and re-vegetated. Caution should always be used in dam reconstruction.
“Seek engineering help whenever in doubt about the safety of a dam,” Beem said. “An earthen dam can look massive and solid but there are millions of pounds of water pushing against it looking for any weakness.”
Beem recommends walking the faces of a dam at least once a year to be able to catch problems before they manifest.
“If all of these steps are followed, you will be doing yourself a great favor by protecting the useful life of your dam and pond,” he said.
--30—
Editor: Sean Hubbard, 405-744-4490, sean.hubbard@okstate.edu
