Hagmaier South, located in Marin, California, is a federal-owned dam managed by the National Park Service. Built in 1944 on Olema Creek, this earth dam stands at a height of 24 feet, with a storage capacity of 20 acre-feet. With a significant hazard potential, the dam's condition assessment is currently listed as "Not Available," and its last inspection was conducted in September 2015.

Despite being under federal ownership and regulation, Hagmaier South does not fall under state jurisdiction or permitting. The dam serves primarily to control water flow and storage in the area, with a normal storage capacity of 13 acre-feet. While the dam's risk assessment, emergency action plan, and inundation maps are not readily available, the National Park Service is responsible for its operations, inspections, and emergency preparedness.

Located in the district of San Francisco, Hagmaier South plays a crucial role in water resource management in the region. With its historical significance dating back to World War II, the dam continues to be a key structure in the National Park Service's portfolio. Climate and water resource enthusiasts would find Hagmaier South's unique characteristics and management under federal oversight intriguing in the context of sustainable infrastructure development and climate adaptation efforts.