Phoenix-area cities and private water companies could soon leave some of their Colorado River water in Lake Mead voluntarily and be repaid with credits from Arizona's underground reserve, under a strategy Central Arizona Project staff described to the CAP board on Thursday, Oct. 1, according to KJZZ.
The reserve belongs to the Arizona Water Banking Authority, a state agency that since the late 1990s has stored surplus river water in aquifers as a hedge against shortages. Instead of the cash payments that fund most conservation deals, participating utilities would get access to some of that stored supply, KJZZ reported.
A small piece of a larger target
Arizona, California and Nevada are working to conserve a combined 700,000 acre-feet or more through 2028, beyond the reductions the federal government requires. Greg Adams, a senior attorney for CAP, said Arizona's goal is about 300,000 acre-feet, according to KJZZ.
Tentative figures Adams presented show the water-bank approach could yield as much as 12,308 acre-feet in 2026, while the 2027 total could reach 56,179 acre-feet. An acre-foot serves roughly three Phoenix-area homes for a year.
Adams acknowledged the savings may be modest. "We're looking at the couch cushions here," he told the board, while saying the offers reflect "broad commitment from water users within the state."
The amounts on the table range widely. Surprise could offer as much as 12,081 acre-feet in 2027, while a Cave Creek water improvement district with a couple hundred customers could offer 25 acre-feet, according to the figures. Adams said the approach would sit alongside paid conservation programs and savings from water users along the river in western Arizona.
Separate from relief for mandatory cuts
The voluntary plan differs from a one-year policy the Water Bank settled on in July, after cities pressed it for clarity. Under that policy, the bank said it would use stored water to replace what utilities lose to required Colorado River reductions, KJZZ reported at the time.
Not every provider wanted the credits handed out that quickly: Terri Sue Rossi of the Arizona Water Company told KJZZ she sees the credits as "an insurance policy against shortages" to be released over time.
