South Magnolia Watershed Site 4, located in Harrison County, Iowa, is a significant water resource managed by the local government. This site, designed by the USDA NRCS, serves multiple purposes including fire protection, stock, and small fish pond. The dam, completed in 1958, is an earth structure standing at 34 feet tall and 515 feet long, with a storage capacity of 106 acre-feet and a surface area of 5.3 acres. The watershed site is regulated by the Iowa DNR and has state permitting, inspection, and enforcement in place to ensure its safety and functionality.

The South Magnolia Watershed Site 4 sits along the TR-WILLOW CREEK and is part of the Rock Island District, with a low hazard potential and a moderate risk assessment rating. Though last inspected in 1965, the dam remains in a not rated condition, indicating a need for further assessment. Despite its age, the dam continues to serve its intended purposes effectively, contributing to fire protection and water storage in the area. Enthusiasts of water resources and climate will find this site fascinating for its historical significance and the role it plays in local water management.

As a key feature in the region's water infrastructure, South Magnolia Watershed Site 4 offers a glimpse into the intersection of human intervention and natural resources. With its earth dam structure and regulated state jurisdiction, this site showcases the efforts to balance water resource management with environmental protection. Its location in Missouri Valley, Iowa, and association with the Natural Resources Conservation Service make it a valuable case study for those interested in sustainable water practices and climate resilience.