US datacenters tripled their water footprint in 10 years

Datacenters in America used about 17 billion gallons of water during 2023, triple the amount they used a decade earlier in 2014, according to an estimate from US Congressional Research Service (CRS). In a recent report published by the Library of Congress, the CRS casts an eye over how server farms use water, looks at potential options to reduce this, and discusses the current federal role in overseeing the use of H2O by operators. The CRS notes the federal government does not systematically assess all water use by the industry - part of the problem is that water usage data is often collected by state-level bodies. Sudden upswing The report says the AI craze has led to a massive surge in datacenter construction since OpenAI released ChatGPT at the end of 2022, which triggered a wave of demand for generative AI and large language models (LLMs). Many new-build data halls are also home to specialized AI hardware, which typically burns much more power (and consequently has greater need of cooling) than older infrastructure. The CRS data says water use in US bit barns had already tripled by 2023, which is the year that the AI-driven infrastructure build boom took off, and it is probable that liquid intake has increased further since then. However, direct use of water - the amount used at the facility itself for thermal regulation, rather than indirect use during off-site power generation - is estimated to make up a relatively small proportion of total US water consumption of about 2 percent. Indirect water consumption via electricity generation made up more than 80 percent of the datacenter's overall water use, the study found. CRS doesn’t go into too much detail about actual cooling systems, noting that datacenters may rely upon different types of technology depending on the size and location of the facility, and the thermal regulation needs of the IT kit. Liquid cooling systems can be more efficient than air-cooled systems, but may not be cost-effective for smaller campuses. Cool runnings As The Register has also previously explained, there are trade-offs between water consumption and power usage. Evaporation-based cooling systems are generally more energy efficient than air-cooled chillers or other waterless systems, but use up much more water. Which system gets chosen may depend on location and climate as much as anything else. Datacenter operators may draw their liquid from various sources, typically municipal drinking water systems, but also treated wastewater or direct withdrawals from surface water or groundwater. The CRS estimates that municipal water systems make up 97 percent of the water supplied to US facilities. The CRS notes that water use charges to operators are often defined in a water service agreement between the municipality and the operator, and these can include provisions that limit the disclosure of this information. The availability of sector-specific or facility-specific data on water usage, such as pertaining to datacenters, is limited. Water utilities may collect water usage data and report it to state or local agencies, if required, however the federal government has not conducted a systematic assessment of water use by the datacenter industry. Partly, this is because water provision is a state-level responsibility. We reported last month how a water resources scientist has filed a lawsuit against Amazon Web Services, alleging it published false and misleading statements about its water use in Northern Virginia, with the evidence drawn from billing and water consumption records obtained using Freedom of Information Act (FOIA) requests sent to water utilities in the region. Pooling the data Federal funding has supported the development of a water use database; researchers from the Virginia Polytechnic Institute and State University have published the United States Water Withdrawals Database, a compilation of water withdrawal data and estimates for 42 states, which includes public supply, industrial, and commercial water use values reported from water users that are required by state law to do so. The CRS report lists a number of bills introduced during this term of Congress that propose to address datacenters and water use through a variety of mechanisms. Some of these bills include provisions to improve the information available about water use by facilities, others seek to incentivize certain practices such as water reuse. Most of these bills have not moved past the introduction stage, CRS says. According to the campaign site Data Center Water Leaks, 36 of 52 state legislatures have introduced some form of water legislation relating to server farms, while California and Arkansas vetoed local bills that were proposed. At the federal level, it says 20 bills are currently active (14 House and 6 Senate), though only three have advanced beyond the referral stage. Outside the US, recent European Union legislation requires datacenter operators to explicitly report annual freshwater consumption, along with other metrics about their facilities. But the European Commission has been facing pushback from the industry about its efforts to enforce greater sustainability. Trade body CISPE warned last year that onerous water regulations could push operators to shift infrastructure outside the EU. More recently, it was reported that the Commission was weakening its proposed environmental rating system for datacenter energy and water efficiency in response to lobbying from the industry. ®