McCollough Dam, located in Denison, Iowa, was completed in 2000 by the USDA NRCS with a primary purpose of grade stabilization along the Tr- East Boyer River. This private-owned earth dam stands at a height of 28 feet and spans 458 feet in length, providing a storage capacity of 62 acre-feet for the surrounding area. The dam's spillway is uncontrolled with a width of 1 foot, and it has a low hazard potential according to the data.

With its location in Crawford County, Iowa, McCollough Dam plays a crucial role in managing water resources and protecting against potential flooding in the region. Operated by the Natural Resources Conservation Service, the dam is regulated by the Iowa DNR and undergoes regular inspections to ensure its structural integrity and functionality. Despite being rated as not assessed in terms of condition, the dam's risk assessment is moderate, highlighting the importance of ongoing risk management measures to mitigate any potential threats to the surrounding community and environment.