Frd No 11, also known as Upper Walnut WS Joint District No 33, is a crucial water resource infrastructure located in El Dorado, Kansas. Owned by the local government and regulated by the Kansas Department of Agriculture, this dam serves the primary purpose of flood risk reduction along the West Branch Walnut River. Built in 1976 by the USDA NRCS, this earth dam stands at a height of 30 feet and has a storage capacity of over 1000 acre-feet.

With a low hazard potential and a moderate risk assessment rating, Frd No 11 plays a key role in managing water flow and reducing flood risks in the area. The dam has not been inspected recently, but it remains in a condition that is not rated. Despite its age, this structure continues to provide essential flood protection and water management services to the community. As a part of the larger water infrastructure network in Butler County, Kansas, Frd No 11 contributes to the overall resilience of the region against flooding events and water resource challenges.