Located in the Scott Creek Watershed in Union, South Dakota, Dam #3 stands as a crucial water resource managed by the local government. Built in 1955 by the USDA NRCS, this Earth dam has a height of 28 feet and a length of 300 feet, with a storage capacity of 59 acre-feet. The dam serves the primary purpose of flood control, with a maximum discharge capacity of 900 cubic feet per second.

Despite being classified as low hazard potential, Dam #3 has not been rated for its current condition as it was last inspected in April 1981. The dam is regulated by the South Dakota Department of Agriculture and Natural Resources, with state permitting, inspection, and enforcement in place. The surrounding area is at risk of inundation in case of a dam failure, highlighting the importance of regular maintenance and updates to the emergency action plan.

Water resource and climate enthusiasts will find Scott Creek Watershed Dam #3 to be a significant structure in managing water flow and preventing flooding in the region. With its strategic location in the Scott Creek watershed and the involvement of various agencies in its regulation and maintenance, this dam serves as a vital asset in safeguarding the local community from potential water-related risks.