California lawmakers seek more transparency on data center water use
As artificial intelligence fuels a new wave of data center development across California, lawmakers are grappling with how to support the growing industry while protecting the state’s limited water supplies.
Two bills moving through the Legislature would give state and local officials a more complete picture of data centers’ water demands. AB 2469 would require developers to disclose projected water use before local governments approve new facilities, while AB 2619 would require operators to report actual water use annually once the facilities open.
Gov. Gavin Newsom vetoed similar legislation last year, saying he was reluctant to impose new reporting requirements on the fast-growing industry without first understanding their impact on businesses and consumers. Advocates of this year’s bills say the industry’s rapid expansion is precisely why lawmakers should act now to better assess its long-term water demands.
“These bills don’t stop data center growth, but they make sure the public and our local water agencies finally get to see what’s happening and start to evaluate the real impacts before it’s too late,” said Kelly Shannon McNeill, LA Waterkeeper’s managing director.
Data centers, which house thousands of computer servers that store and transmit digital information, often require water-intensive cooling systems to prevent overheating. According to Pew Research, California is home to 330 data centers and counting.
McNeill said that cities and counties are currently being asked to approve some of the largest water users in their jurisdiction areas without knowing how much water they will use, where it will come from and who will pay for it.
Opponents argue existing laws already provide local agencies with the information they need to evaluate proposed data centers. They also contend data centers are not uniquely water-intensive compared with other commercial and industrial facilities, making it unfair to subject them to additional reporting requirements.
Kristopher Anderson is a policy advocate with the California Chamber of Commerce, which opposes the bill. He said the organization agrees local governments need information to evaluate proposed data centers, but believes existing laws already provide it.
“The question is, do they currently not have the information necessary to provide a reliable water supply when a data center is proposed within their service territory?” Anderson said. “What we’re saying is that existing law is already providing that transparency and that information to those water agencies.”
However, researchers dispute that conclusion.
A February report by the UC Berkeley Center for Law, Energy & the Environment found California’s oversight of data center water use relies on a patchwork of policies and regulations with significant gaps. A separate report released in May by Next 10 and Santa Clara University discovered those gaps allow some projects to avoid comprehensive review as data center development increasingly shifts toward water-stressed, vulnerable and rural communities.
“My bills do hope to get at that transparency so that cities can make informed decisions,” said Assemblymember Diane Papan, D-San Mateo, who introduced this year’s legislation after Newsom vetoed the bill she authored last year. “I don’t think transparency ever hurt anybody, quite frankly.”
Papan said she is “tremendously optimistic” about the bills, which recently passed the Assembly. She reintroduced the legislation because public concern over data center development has grown, she said, and she believes California has an opportunity to lead other states in addressing the issue.
Opponents, however, argue the legislation could undermine California’s leadership in the technology industry.
“We believe any requirements for reporting, assessments and classification systems should strike a balance of addressing resource planning needs without imposing unnecessary burdens on the industry,” said spokesperson for the Data Center Coalition in a statement. “This legislation would fail to meet those benchmarks and would instead make the state less competitive for future investment.”
Papan rejected the notion that technological innovation and water conservation are at odds. She said the bills are intended not to regulate data centers, but to give local communities the tools they need to evaluate proposed projects.
Although, some local government organizations have also raised concerns about the legislation, saying it imposes additional state requirements on a process that should remain entirely under local control.
“I support autonomy in decision-making for local governments to the extent that it’s in alignment with state law, but what does autonomy really mean?” said Michael Kiparsky, one of the UC Berkeley study’s authors. “I think to make a decision without full information and understanding is more like an illusion of autonomy.”
This story was originally published July 15, 2026 at 5:00 AM with the headline "California lawmakers seek more transparency on data center water use."
