Arnold, located in Goshen, Wyoming, is a vital structure on the North Platte Offstream, designed by JOHN R LONG in 1968 for flood risk reduction. This Earth-type dam stands at 33 feet tall with a hydraulic height of 28 feet and a length of 300 feet, providing a maximum storage capacity of 2639 acre-feet and a normal storage of 1134 acre-feet. Despite its low hazard potential and fair condition assessment, Arnold has been deemed to have a moderate risk level.

Managed by a private owner, Arnold is under state jurisdiction and regulation, with permitting, inspection, and enforcement overseen by the State Engineer's Office in Wyoming. The dam features an uncontrolled spillway, one outlet gate, and a spillway width of 50 feet. Its primary purpose remains flood risk reduction, serving as a crucial infrastructure component in protecting the surrounding area from potential water-related disasters.

With its strategic location in Morrill, Nebraska, Arnold plays a significant role in mitigating flood risks and ensuring the safety of nearby communities. As a point of interest for water resource and climate enthusiasts, Arnold stands as a testament to the importance of effective dam infrastructure in managing water resources and enhancing resilience in the face of changing environmental conditions.