De Geus Dam, located in Marion, Iowa, near the Red Rock Reservoir, was completed in 1999 by the USDA NRCS and serves multiple purposes including fire protection, stock, and small fish pond. This privately owned earth dam stands at a height of 26 feet and a length of 300 feet, with a storage capacity of 25 acre-feet. The dam is situated on Wildcat Creek and is designed to have a low hazard potential, with a moderate risk assessment score of 3.

Despite being privately owned, De Geus Dam is not regulated or inspected by the state, and there are no state permits or enforcement measures in place. The dam's spillway is uncontrolled, and there are no outlet gates or associated structures. While the condition assessment is listed as "not rated," the risk management measures and emergency action plan status are not specified. Overall, De Geus Dam presents an intriguing case study for water resource and climate enthusiasts, as it highlights the importance of private ownership and maintenance in ensuring the safety and sustainability of water infrastructure.