Frd No 4, also known as the Little Walnut Hickory Watershed Dam, is a local government-owned structure located in Leon, Butler County, Kansas. Constructed in 1966 by the USDA NRCS, the primary purpose of this Earth-type dam is flood risk reduction in the NO BR Little Walnut River-TR watershed. With a height of 34 feet and a storage capacity of 1753.86 acre-feet, it plays a crucial role in protecting the surrounding area from potential flood events.

Operated and regulated by the Kansas Department of Agriculture, Frd No 4 is considered to have a low hazard potential and a moderate risk assessment rating. Despite its age, the dam has not been rated for its condition, and no recent inspections have been recorded. While it lacks certain features like outlet gates and spillway width information, this structure continues to serve its purpose effectively as part of the flood risk reduction infrastructure in the region.

Given its location and importance in the local water resource management system, Frd No 4 is an essential asset for climate and water resource enthusiasts to study and monitor. As climate change continues to impact the frequency and intensity of extreme weather events, understanding and maintaining the integrity of structures like this dam are vital for ensuring the safety and resilience of the surrounding communities and ecosystems in the face of future challenges.