Data centers have been in California for a long time, and the number and size of facilities are growing to support the rapid boom of artificial intelligence. Oversight, though, has not kept pace with development. In particular, from a water supply perspective, we do not know how much water data centers are using to cool their operations.
The Problem: Growing Water Usage & Location Concerns
While data centers’ water consumption may currently represent a small portion of the state’s water demand as a whole, it is growing rapidly – nearly doubling from 2019 to 2023 – with near-future demand expected to rise up to 4.6 times greater than 2019 levels.[1] Unlike other industries, data centers also primarily rely on potable water for on-site use.
The total volume of a facility’s water use is far from the only relevant factor in determining its water-related impact. “Hyperscale” facilities in California are disproportionately sited in low-income communities and areas with greater water scarcity, compounding existing risks to vulnerable California residents.[2] Meaningfully assessing the impact of a data center’s water use requires viewing that use in a local context.
A Lack of Transparency
California currently does not require data centers to report on their water use. The total amount of water used, proportion of direct to indirect use, and water source(s) remain opaque for many facilities. Often, data centers do not undergo full environmental review, and what environmental data may be available is voluntarily reported by project operators in corporate sustainability reports. Globally, less than half of companies that own or operate data centers collect data on water usage for corporate sustainability purposes.[3]
The amount of water used by data centers varies greatly based on a number of factors, including the site’s climate, the source of energy generation, the type of cooling technology employed, and whether the facility recycles water. Several legislative proposals have been introduced to help local governmental entities and the public better understand how much water data centers use and for what purposes.
Last year, Governor Newsom vetoed Assembly Bill 93, authored by Diane Papan, which would have required data centers to report their expected water use prior to applying for business licenses, and to certify their actual annual water use when renewing business licenses.