Datacenter water use? California governor says don't ask, don't tell

California Governor Gavin Newsom has vetoed legislation requiring data centers to disclose their water consumption, even as he champions efforts to address the state's water scarcity challenges.

Assembly Bill 93 would have mandated that data center operators provide water suppliers with estimates of expected usage before obtaining business licenses, followed by annual reports of actual consumption when renewing permits. However, in an October 11 letter [PDF] to the California State Assembly, Newsom declined to sign the bill.

"While I appreciate the author's intent, I am reluctant to impose rigid reporting requirements about operational details on this sector without understanding the full impact on businesses and the consumers of their technology," Newsom wrote.

Newsom also noted AI-driven demand for datacenter capacity throughout the nation, and as "the global epicenter of the technology sector," California is strategically positioned to support infrastructure development within the state - and he doesn't want to do anything that may discourage this.

According to the bill's sponsor, assembly member Diane Papan, the legislation would have enabled the Department of Water Resources to categorize datacenters into tiers based on factors affecting water consumption, and apply appropriate standards for each tier.

The proposal comes as California faces ongoing water challenges. The latest US Drought Monitor (USDM) map for the state shows large areas currently abnormally dry or even in extreme drought.

The governor announced a new reservoir infrastructure project in August, saying at the time: "We can't wait to protect our state from water shortages - there are 40 million Californians depending on us. I am pleased to see the Sites Reservoir project move forward with additional funding, and urge the Legislature to continue to make our state's water future a priority."

The topic of datacenter water consumption remains contentious, with some sources claiming that massive bit barns chug through up to 5 million gallons per day, equivalent to the water use of a town populated by 10,000 to 50,000 people. Some players in the industry like to claim that it isn't really that big a problem, however.

It isn't just California where this debate is raging. An unusually hot and dry summer in Europe has raised concerns about the availability of water and the impact of high-density, heat-intensive infrastructure used for AI training.

The European Commission unveiled a water resilience strategy for the region earlier this year, and this was met with suggestions from Cloud Infrastructure Service Providers in Europe (CISPE), a trade body representing cloud operators.

It called for measures to support Europe-wide schemes for the treatment and reuse of municipal wastewater for uses such as datacenter cooling, but also warned about imposing new water regulations, saying these risk "shifting infrastructure outside the EU" - in other words, they might take their bit barns and play elsewhere. ®