The best solution for preventing muskrats from burrowing into dams is to properly construct the dam. Good dam construction should include the following:

1. A dam with an inner face having a slope of 3:1, outer face 2:1, eight feet wide at the top, three feet of freeboard and good grass cover with no grazing by livestock. 

2. A spillway to prevent water from rising more than six inches on the dam.

3. Bank stabilization using riprap (large rocks), a 6 -to 12-inch layer of sand or pea gravel or 1 x 2 inch mesh wire laid against the bank. Banks should be stabilized at least two feet above and three feet under the normal surface water level.

Earthen dams can be protected by cutting a narrow trench down the center of the dam and filling it with concrete. The trench should extend three feet below the water and should be filled with concrete to one foot above the normal high-water level. This barrier will prevent muskrats from burrowing completely through the dam and causing a leak.

Contact your local Soil Conservation Service, fish and wildlife district biologist or Extension aquaculture or wildlife specialist for more information on proper pond construction.

Another method of reducing muskrat problems is to remove their habitat or food supply (cattail, burreed, rushes, sedges and arrowhead). Unfortunately, this also decreases cover for a variety of desirable fish and wildlife species.