Modifying Sites to Discourage Beaver
Whenever possible, include beaver damage prevention, control techniques, or structures in the initial engineering plans. For instance, where it is feasible, trees and shrubs on the banks of streams and ditches should be removed. This eliminates material beavers might use to construct dams and/or use as a food source. This can be particularly effective along agricultural drainage ditches and immediately upstream and downstream of road culverts.
To make mowing easier, the banks of drainage ditches and man-made ponds should be gently sloped. This discourages beaver from burrowing and minimizes the probability of dam construction. (Note: Without an Article 24/15 Permit, it is a violation of The Environmental Conservation Law to disturb the bed or banks of any protected stream).
Beaver activity can also be discouraged by eliminating pools and creating riffle areas leading into road culverts. This can be accomplished through mechanical grading and placement of coarse stone or rubble in the stream bed.
This prevents beavers from obtaining mud and/or from moving material to a site which they have previously dammed. Beaver are also less likely to construct dams in high gradient areas. Again, this is most effective when all vegetation is removed from the immediate area.
Beaver control technology should be incorporated into engineering designs for pond and marsh construction. In shallow water impoundments, dikes should be constructed with wide bases, gentle slopes, and be no higher than the top of the water control box. The control should be an in-line water control structure placed in the center of the dike or as far away from the intake as possible. The top of the box should be protected with a locked cover. Water levels should be maintained so that the intake remains completely under water. The intake should also be protected with a deep water cage or fence to prevent beaver or flood debris from plugging it. To facilitate mowing of the dike, the control box can be set at grade on the top of the dike.
The objectives of this design are two-fold. One is to construct a wide, low level dike which minimizes the washout potential. The other objective is to disguise the flow of water at the intake and protect the water control box from beaver activity.