Including the North Platte River, South Platte River and the Laramie River Basins 


                Jeff Cowley
                River Basin Coordinator
                122 W. 25th St.
                Herschler Building, 1st Floor West 
                Cheyenne, WY 82002

                Steve Wolff
                Division Administrator 
                122 W. 25th St. 
                Herschler Building, 1st Floor West
                Cheyenne, WY 82002 

Modified North Platte Decree

The U.S. Supreme Court revisited Nebraska v. Wyoming (1945) in 1953, 1993, 1995, and 2001. The 2001 Modified Decree expanded the limitation on irrigation in Wyoming to include both consumptive use and irrigated acreage above Guernsey Reservoir. The Modified Decree added a consumptive use cap for irrigation purposes above Guernsey Reservoir (except Casper/Alcova Irrigation District) and expanded the 1945 Decree's limitation on irrigated acreage above Guernsey Reservoir (with the same exception) to include tributaries between Pathfinder and Guernsey Reservoirs. The Court remained consistent in support of the historic sectionalized administration of the river, where available flows have been equitably apportioned between the states with certain specified limitations on acreage, consumptive use, and reservoir storage. The 2001 Modified Decree and related settlement stipulations also provided for an automatic priority call for the mainstem federal North Platte River reservoirs in Wyoming when forecasted water supplies are less than 1.1 million acre feet.

Platte River Recovery Implementation Program

On January 1, 2007, the State of Wyoming entered into the Platte River Recovery Implementation Program (PRRIP) with the U.S. Department of the Interior and the States of Colorado and Nebraska. The purpose of the PRRIP is to ensure continued use and development of Wyoming’s water in the Platte River basin while maintaining compliance under the Endangered Species Act (ESA). To define the water use covered by the PRRIP, Wyoming’s Depletions Plan was developed. In the plan, water use covered by the PRRIP is based on a depletion baseline that occurred from 1992 through 1996. Under the PRRIP, Wyoming must annually measure and compare its current water use (depletions) against the thresholds for depletions that were quantified for that 1992-1996 period.



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