Knott Retention Reservoir, also known as the Duane Knott Retention Reservoir, is a private water resource structure located in Redwood County, Minnesota. Built in 1974 by the USDA NRCS, this Earth-type dam serves primarily for irrigation purposes along the Cottonwood River. With a height of 32 feet and a storage capacity of 55 acre-feet, the reservoir provides a vital water source for local agricultural needs.

Managed by the Minnesota Department of Natural Resources, Knott Retention Reservoir has a low hazard potential and is classified as being in satisfactory condition. The dam features uncontrolled spillways and outlet gates, ensuring proper water flow regulation. Despite its moderate risk assessment rating, the reservoir has not undergone any major modifications since its completion, emphasizing its reliability in water retention and flood control.

Situated within the Omaha District and under the jurisdiction of the MNDNR EWR, Knott Retention Reservoir plays a crucial role in supporting the region's water management efforts. With its strategic location and efficient design, this reservoir stands as a testament to effective collaboration between private and governmental entities in safeguarding water resources and adapting to changing climate conditions.