Eastern Wildlife Damage Control Conferences


Date of this Version

October 1987


Since 1978 there has been a continual effort by Region 9 of the New York State Department of Environmental Conservation to develop devices capable of protecting road culverts from plugging damage by beavers (Castor canadensis). Various protective devices were developed. The most successful was the T-culvert guard. Trial installations of T-culvert guards were made at 4 sites experiencing beaver damage. T-culverts consisted of a 4 ft. or larger diameter culvert and a smaller diameter culvert which connected it to the road culvert . Directions for construction, installation and maintenance of T-culverts are given. Costs for a typical 4 ft. diameter T–culvert at 1985 prices were $226.00 for materials, $160.00 for backhoe rental and 3 worker days for labor. Average annual maintenance cost was estimated to be .27 worker days and .27 hrs. of backhoe time. T-culverts alleviated beaver damage by concealing flows which were considered detectable to beavers. It is believed that these devices may prove useful in protecting water level control structures such as are used in ponds and marshes.