Harlan County Reservoir was built to provide flood control and the authorized multipurpose uses of irrigation, recreation, fish and wildlife management and sediment accumulation.
Specific storage capacity was allocated by Congress for both flood control and irrigation. The U.S. Bureau of Reclamation coordinates the irrigation releases from Harlan County Reservoir. The Kansas City District, U.S. Army Corps of Engineers coordinates the flood control releases, as well as operation and maintenance of the dam structure and surrounding land.
The top of the multipurpose pool at Harlan County Reservoir is 1,945.73 feet and has a total storage capacity of about 314,000 acre-feet. Irrigation has a dedicated storage capacity of 150,000 acre-feet within the multipurpose pool. The remaining available 164,000 acre-feet of multipurpose storage is shared between sediment accumulation, recreation and fish and wildlife management.
Daily releases from the multipurpose pool are coordinated by the U.S. Bureau of Reclamation and the irrigation districts in Nebraska and Kansas. Releases to the river are not based on recreation activities like tubing, canoeing or fishing in the stilling basin below the dam.
Inflows this year are the lowest since 2006 and have not been sufficient to fill the multipurpose pool. During drought years, when the lake is unable to fill, the dwindling supply is shared among the authorized operating purposes under the terms of the Consensus Plan for Harlan County Reservoir.
To balance multipurpose pool needs, the Consensus Plan limits irrigation releases. In 2025, the lake is unable to provide irrigators with their maximum allowed volume of water (approximately 100,000 acre-feet is available versus 150,000 acre-feet maximum). Therefore, irrigation releases will shut off if the pool elevation drops to 1,929.3 feet.
Ultimately, as the Water Control Manual states, Harlan County Reservoir was built primarily to provide irrigation water and flood control. It also acknowledges irrigation drawdowns may have an adverse effect on recreation aspects of the reservoir.