Big Creek Terminal Dam, also known as Big Creek Lake, is a federal-owned structure located in Polk, Iowa, managed by the US Army Corps of Engineers. Completed in 1972, this gravity-type dam stands at a height of 70 feet and has a storage capacity of 27,500 acre-feet. Its primary purpose is flood risk reduction along the Big Creek Diversion Channel, with a normal storage capacity of 15,600 acre-feet and a maximum discharge of 33,000 cubic feet per second.

Although categorized as having a low hazard potential, the dam is continually monitored and managed by the USACE to address flood risks associated with its operation. Regular inspections, maintenance, and emergency action plans are in place to ensure the structural integrity of the dam and mitigate potential risks. The USACE collaborates with local emergency managers and the public to raise awareness and readiness in the event of a dam-related emergency, emphasizing the importance of preparedness and response measures. Overall, the Big Creek Terminal Dam serves as a vital component in managing water levels and protecting downstream areas from flooding, showcasing the commitment to effective risk management and safety by the US Army Corps of Engineers.