Mccoy is a private dam in Iowa, Wisconsin, designed by the USDA NRCS and regulated by the WIDNR. Completed in 1974, this earth dam serves multiple purposes including fire protection, stock, and small fish pond management. With a height of 19 feet and a length of 335 feet, Mccoy has a storage capacity of 60 acre-feet and a normal storage capacity of 21.5 acre-feet. The dam has a low hazard potential and is considered to be in fair condition as of the last assessment in March 2021.

Situated on the TR Blue Mounds Branch, Mccoy has a drainage area of 0.5 square miles and a surface area of 5 acres. The dam has a maximum discharge capacity of 60 cubic feet per second and an uncontrolled spillway type. While the risk assessment for Mccoy is moderate, the dam meets inspection and enforcement standards set by the state regulatory agency. With its strategic location in Blanchardville and contribution to water resource management, Mccoy stands as a valuable asset for the community and the environment.