Water experts say not to blame data centers for Arizona’s Colorado River cuts
Despite Arizona facing deep cuts in Colorado River water, experts currently do not blame data centers for the state's water shortage, though concerns about their growing water and power consumption are high. Arizona's Attorney General called for a pause on new data center construction, which the Governor rejected, but the Governor did enact a three-year moratorium on new tax breaks for data centers. Transparency on water usage remains a challenge as companies are not required to report it publicly.
Water experts assert that data centers are not the primary cause of Arizona's Colorado River water crisis, despite public concern and the state facing significant water cuts. However, researchers like Rhett Larson, a professor of water law at Arizona State University, acknowledge that data centers are growing rapidly and use substantial amounts of water, an issue complicated by the lack of public reporting requirements for their water consumption.
Following a federal plan issued by the Bureau of Reclamation on August 21 to reduce Arizona's Colorado River consumption by 760,000 acre-feet, Arizona Attorney General Kris Mayes called for a pause on new data center construction. Governor Katie Hobbs, while rejecting the construction pause, signed a budget bill in June that includes a three-year moratorium on new tax breaks for data centers. A previous proposal by Gov. Hobbs in January for a 1 cent per gallon water fee for data centers, estimated to generate $6 million annually, did not advance.
Details on exact water usage by data centers remain elusive, as the Arizona Department of Water Resources does not track usage for most facilities, and water utilities cite privacy policies. Nell Green Nylen, a senior research fellow at the University of California at Berkeley's Wheeler Water Institute, highlighted the difficulty in assessing the scale of data center water use. While some companies like Iron Mountain use closed-loop cooling to conserve water at their Phoenix and Scottsdale facilities, the total usage depends on various factors including power source and cooling systems. Agriculture remains the largest water consumer in the state, accounting for 72% of usage, prompting discussions on whether Arizona values data centers enough to reallocate water from farms.
In California, a similar bill authored by Assemblymember Diane Papan, requiring data centers to report projected water usage before applying for licenses, awaits Governor Gavin Newsom's signature. This reflects a broader trend of increased scrutiny on data center resource consumption across the western U.S., with pending proposals also in Congress.