Dd No 4 (Sp-4) is a local government-owned dam located in El Dorado, Kansas, designed by George Schurr and completed in 1994. This earth dam stands at a height of 24 feet and spans a length of 1300 feet, providing flood risk reduction along the Walnut River. With a storage capacity of 857.4 acre-feet and a drainage area of 1.89 square miles, this dam plays a vital role in controlling debris and reducing the risk of flooding in the area.

The dam has a low hazard potential and has not been rated for its condition assessment. While it has not been inspected since July 1995, it is regulated by the Kansas Department of Agriculture and meets state permitting, inspection, and enforcement requirements. The spillway of Dd No 4 (Sp-4) is uncontrolled, with a width of 40 feet, and there are no outlet gates associated with the structure. Despite moderate risk factors, this dam serves as a crucial infrastructure for managing water resources and climate-related challenges in Butler County.

Overall, Dd No 4 (Sp-4) serves as an essential flood risk reduction measure in El Dorado, Kansas, providing protection against potential inundation and ensuring the safety of residents in the area. With its strategic location along the Walnut River and a storage capacity of 857.4 acre-feet, this dam plays a significant role in managing water flow and controlling debris during periods of heavy rainfall. While it may require further assessment and inspection to ensure its continued effectiveness, Dd No 4 (Sp-4) remains a key component of the local water resource infrastructure in Butler County.