Located in Ottumwa, Iowa, Jefferson Park Watershed Site 5 is a flood risk reduction structure along the TR-Des Moines River. Built in 1985, this earth dam stands at 43 feet high with a length of 930 feet, providing a storage capacity of 228 acre-feet. The dam serves the primary purpose of flood risk reduction, with additional benefits for recreation in the area.

Managed by the Iowa Department of Natural Resources, Jefferson Park Watershed Site 5 is regulated, inspected, and enforced by state authorities to ensure its safety and functionality. With a high hazard potential but a satisfactory condition assessment as of June 2019, the dam is monitored regularly to mitigate risks and ensure public safety. The structure's design by SCS and critical role in protecting the surrounding Wapello County highlight its importance in managing water resources and climate impacts in the region.