Dd No 1, located in Medora, Kansas, is a local government-owned earth dam designed by Booker & Freund. It serves the primary purpose of flood risk reduction along the Little Arkansas River. With a dam height of 29.3 feet and a storage capacity of 1193.11 acre-feet, it plays a crucial role in managing water resources in the area.

Despite being deemed to have a low hazard potential, Dd No 1 is regulated by the Kansas Department of Agriculture and undergoes regular inspections, permitting, and enforcement. The dam, with a spillway width of 40 feet, has a normal storage capacity of 212.03 acre-feet and covers a surface area of 34.93 acres. Its drainage area spans 2.47 square miles, contributing to its significance in flood risk reduction efforts in McPherson County.

With a moderate risk assessment rating, Dd No 1 is a key infrastructure for water resource management in Kansas. Its strategic location and design make it an essential component in the state's efforts to mitigate flood risks and ensure the safety and security of the surrounding communities.