Lake Oelwein Dam, located in Fayette County, Iowa, was completed in 1908 and serves as a recreational resource for the local community. The dam stands at 16 feet high and spans 195 feet in length, with a storage capacity of 200 acre-feet. Positioned on Otter Creek, the dam is regulated by the Iowa Department of Natural Resources and undergoes regular inspections to ensure its structural integrity.

Despite being categorized as having a low hazard potential, the dam carries a moderate risk assessment of 3 out of 5. While it has not been rated for its current condition, the dam remains a key feature in Hazleton's landscape and offers opportunities for outdoor activities such as fishing, boating, and picnicking. With its uncontrolled spillway and soil foundation, Lake Oelwein Dam stands as a testament to early 20th-century engineering and continues to provide both recreational enjoyment and essential water resource management for the region.