- Areas of trees, brush, and open water provide ideal habitat for burrowing animals.
- An overabundance of rodents increases the chance of animal burrowing, which creates holes, tunnels, and caverns.
- Tunnels may reduce the required length of the seepage path, which could cause internal erosion of the dam.
- Tunnels can lead to the collapse of the dam crest and may cause dam failure.
- Rodent holes make earthen spillways more susceptible to erosion when flow passes through the spillway.
- Remove trees and brush from the dam and surrounding areas to reduce attractive habitat.
- Start a rodent control program to reduce the population and prevent future damage to the dam.
- Backfill existing rodent holes with mud-pack. Mud-pack is made by adding water to a 90 percent earth and 10 percent cement mixture until a slurry of thin cement consistency is attained.
- Large holes may need to be excavated and backfilled with compacted soil.