Keep dams mowed to help maintain an effective grass cover. Don't allow trees and brush to grow on the dam or in the emergency spillway. Tall, heavy weeds and brush invite undesirable rodent habitation and burrowing. Burrowing animals can cause seepage through a dam, which may lead to dam failure. Fill burrows with compacted soil.
Eliminate animal burrows in the dam to prevent failure.
Rock riprapping to well below the waterline will discourage muskrat burrowing. Unless special drainage features are constructed in the dam, water should not pass through, under or around it. Remove debris from the pipe spillway inlet area. Be sure pipe spillways are sound and properly aligned. Use a small hammer to determine if the pipe wall is weak.