Mill Creek Lake Dam, located in Paullina, Iowa, is a state-owned earth dam that was completed in 1934 for the primary purpose of recreation. The dam stands at a height of 29 feet and has a length of 622 feet, creating a reservoir with a storage capacity of 500 acre-feet and a surface area of 40 acres. The dam is situated on Cole Creek, within the O'Brien County of Iowa, and is regulated by the Iowa Department of Natural Resources.

Despite its low hazard potential and a satisfactory condition assessment, Mill Creek Lake Dam poses a moderate risk, as indicated by a risk assessment rating of 3. The dam features an uncontrolled spillway with a width of 80 feet, and is subject to regular state inspections, maintenance, and enforcement to ensure its structural integrity and safety. While the dam has not undergone any major modifications over the years, it remains a significant part of the water resource infrastructure in the region.

With its serene surroundings and recreational opportunities, Mill Creek Lake Dam serves as a popular destination for water and climate enthusiasts alike. Whether it's fishing, boating, or simply enjoying the scenic beauty of the reservoir, visitors can appreciate the importance of this earth dam in providing both leisure and flood control benefits to the local community. As efforts continue to manage the dam's risk and ensure its long-term sustainability, it remains a key feature in the water resource management of O'Brien County, Iowa.