Arizona v. California

2 Analyses of this case by attorneys

  1. U.S. Bureau of Reclamation Releases Updated Operation Plan for Colorado River System Reservoirs

    Snell & Wilmer L.L.P.Cynthia ChandleyAugust 15, 2014

    As such, if Reclamation’s 24-month study prediction holds true, there will be a shortage declared for the 2016 water year. The impact of a shortage declaration would be felt most significantly in Arizona – but the overall impacts are likely to reverberate throughout the Colorado River Basin.Under the decree in Arizona v. California, 373 U.S. 546 (1963), most recently revised at 531 U.S. 1 (2000), Arizona is entitled to 2.8 million acre-feet of Colorado River water each year.Nevada is allocated 300,000 acre-feet and California is allocated 4.4 million acre-feet.However, under the Shortage Sharing Criteria set forth in the Interim Guidelines, if a shortage is declared, Arizona’s allocation would be reduced by 320,000 acre-feet and Nevada’s allocation would be reduced by 13,000 acre-feet.In contrast, a shortage declaration in 2016 will not reduce California’s Colorado River supply.California will continue to receive its full allocation of 4.4 million acre-feet per year as specified in the Arizona v. California decree.A reduction to Arizona’s allocation in 2016 would directly affect deliveries of water through the Central Arizona Project (CAP) canal.Reductions would come out of the “non-Indian Agricultural” portion of the CAP water supply.

  2. Winters Water Rights Revived After Navajo Nation Case

    Schwabe, Williamson & Wyatt PCApril 12, 2022

    The Law of the River’s origin traces to 1922, when states throughout the Colorado River Basin signed a compact to apportion the River’s water equally between the “Upper Basin” states (Colorado, New Mexico, Utah, and Wyoming) and “Lower Basin” states (California, Arizona, and Nevada), with each group receiving 7.5 million acre-feet per year (“mafy”).The United States conditionally approved that interstate compact in 1928 through the Boulder Canyon Project Act, which became effective by presidential decree on June 25, 1929, and was adjudicated in Arizona v. California, 373 U.S. 546 (1963). The BCPA apportioned Colorado River water between the Upper Basin and Lower Basin states, but it did not allocate water within each group.