Located in Winfield, Kansas, Frd No 21, also known as Timber Creek Watershed Dam No 21, is a crucial structure designed by the USDA NRCS for flood risk reduction. Built in 1975, this earth dam stands at 39.7 feet high with a hydraulic height of 42 feet and a structural height of 48 feet. Its primary purpose is flood risk reduction, serving the Richland Creek area with a normal storage capacity of 294 acre-feet and a maximum discharge of 4092 cubic feet per second.

The dam covers a drainage area of 6.96 square miles and has a storage capacity of 3882 acre-feet. With a surface area of 54 acres and a length of 2438 feet, Frd No 21 plays a vital role in managing water resources in Cowley County, Kansas. Despite being assessed as in fair condition with a high hazard potential, the dam is regularly inspected by the Kansas Department of Agriculture to ensure its structural integrity and public safety.

In the event of emergencies, the dam has a hazard potential rating of 3, indicating a moderate risk level. With its uncontrolled spillway type and a spillway width of 80 feet, Frd No 21 is a critical infrastructure for flood control in the region. Its location in the Timber Creek Watershed highlights its significance in safeguarding the local community and environment from the impacts of extreme weather events and flooding.