Arizona data centers drive up water demand, but not the way you might think
Data centers in the Phoenix area use relatively little water directly for cooling, but their substantial electricity demand can drive significant water consumption at power plants. Phoenix and other Arizona municipalities have adopted large-water-user rules, while limited utility reporting makes the full water impact difficult to measure.
Data centers in the Phoenix area generally have modest on-site water needs, with some facilities using closed-loop or zero-water cooling systems. Researchers Sarah Porter and Kathryn Sorensen of Arizona State University’s Kyl Center for Water Policy said municipal review of large water users provides a safeguard, and Phoenix requires projects seeking to use at least 250,000 gallons per day to submit conservation plans.
The larger concern may be indirect water use from electricity generation. Arizona Public Service is expanding its Redhawk natural gas plant near Arlington to add 397 megawatts as power demand rises, and researchers say gas, nuclear and coal plants can consume substantial water. The Arizona Corporation Commission does not require utilities to report water use at generating facilities, prompting criticism from utility researchers and environmental advocates who say the lack of data prevents a clear assessment of data centers’ impact on the state’s constrained water supplies.