Hopp Dam (Upper Site) in Mills County, Iowa, is a privately owned earth dam designed by USDA NRCS and completed in 2005 for grade stabilization purposes. The dam stands at a height of 36 feet and spans a length of 655 feet, with a storage capacity of 87 acre-feet. Situated on a tributary to Silver Creek, the dam serves multiple purposes including fire protection, stock watering, and recreational activities for the local community.

Managed by the Iowa Department of Natural Resources, Hopp Dam is regulated and inspected regularly to ensure its safety and compliance with state guidelines. The dam has a low hazard potential and has not been rated for its condition assessment. Despite its relatively small drainage area of 0.38 square miles, the dam plays a crucial role in managing water resources in the region and provides a valuable habitat for small fish populations.

With its strategic location in Malvern, Iowa, Hopp Dam (Upper Site) offers a unique opportunity for water resource and climate enthusiasts to study the impact of earth dams on local ecosystems. Its association with the Omaha District of the US Army Corps of Engineers further highlights its importance in flood control and water management efforts in the area. As a key infrastructure for grade stabilization, the dam contributes to the preservation of water quality and the enhancement of recreational opportunities for residents and visitors alike.