The Mill Picayune Watershed Site M-22-13 in Shelby County, Iowa, is a local government-owned earth dam completed in 1978 by the USDA NRCS. This dam serves multiple purposes, including fire protection, stock and small fish pond, and flood risk reduction. With a height of 38 feet and a length of 550 feet, the dam has a storage capacity of 59 acre-feet and covers a drainage area of 0.2 square miles along the TR-Mill Creek.

Managed by the Iowa DNR, this dam has a low hazard potential and a moderate risk assessment rating. The spillway type is uncontrolled, and the dam's condition is currently not rated. While the dam is primarily used for water resource management, it also plays a crucial role in protecting the surrounding area from potential flood risks. With its strategic location and design, the Mill Picayune Watershed Site M-22-13 stands as an essential infrastructure for water resource and climate enthusiasts in the region.

Overall, this dam represents a significant investment in water resource management and flood risk reduction in the Manteno area. With its long history of service and strategic importance, the Mill Picayune Watershed Site M-22-13 serves as a testament to the importance of sustainable water resource infrastructure for local communities. Moving forward, continued monitoring and maintenance of this dam will be essential to ensure its continued effectiveness in managing water resources and protecting the surrounding area from potential flooding events.