Dd No 121, located in Jackson County, Kansas, is a local government-owned Earth dam designed by Miles Engineering & Surve for flood risk reduction along the Cross Creek-TR river. Standing at 30 feet tall and 100 feet long, this dam has a storage capacity of 296 acre-feet, with a normal storage level of 39.8 acre-feet and a drainage area of 0.99 square miles. The dam's spillway, which is uncontrolled, is 40 feet wide and can handle a maximum discharge of 1128 cubic feet per second.

Despite being classified as having a low hazard potential and not having a condition assessment rating, Dd No 121 presents a moderate risk level according to the data. The dam has not been inspected since April 2010, and it is not equipped with outlet gates or locks. The emergency action plan (EAP) status, risk management measures, and inundation maps for the dam are currently unknown, highlighting the need for updated assessments and preparations to ensure the safety and efficiency of this vital flood risk reduction structure in Kansas.