Arizona is set to absorb the largest share of new federal Colorado River cuts beginning in 2027, losing 760,000 acre-feet annually under a two-year plan intended to protect Lake Powell, Lake Mead and critical dam infrastructure.
ABC News reported the U.S. Department of the Interior finalized operating guidelines Friday requiring Arizona, California and Nevada to reduce Lower Basin deliveries by 1.25 million acre-feet each year in 2027 and 2028. If the states implement their May agreement, California would lose 440,000 acre-feet and Nevada 50,000. The guidelines call for another 700,000 acre-feet of voluntary conservation over the two years.
Arizona’s reduction is 48% larger than its current 512,000-acre-foot Tier 1 cut and equals roughly 27% of its Colorado River allocation. Nearly all existing reductions have fallen on Central Arizona Project users. The 336-mile canal delivers water to Maricopa, Pinal and Pima counties, including the Phoenix and Tucson metropolitan areas.
The decision followed the lowest snowpack on record for the basin. Federal documents say combined storage in Lake Powell and Lake Mead is lower than at any point since before Lake Powell began filling in 1963. The guidelines seek to keep Lake Powell at or above 3,510 feet to preserve operations at Glen Canyon Dam, but deeper reductions remain possible after 2028.
Democratic Arizona Gov. Katie Hobbs praised the agreement for providing two years of stability and avoiding a federal scenario that could have cut 77% of Central Arizona Project supplies. She nevertheless criticized Colorado, New Mexico, Utah and Wyoming for avoiding mandatory reductions and said Arizona could defend its rights through litigation.
Arizona Department of Water Resources Director Tom Buschatzke said the guidelines provide short-term stability while negotiations continue. State lawmakers must still approve the three-state sharing agreement.
