US data centers tripled water use to 17 billion gallons in 2023, CRS report finds

Water use tripled in under a decade

US data centers consumed an estimated 17 billion gallons of water in 2023, roughly three times what they used in 2014, according to a Congressional Research Service (CRS) report. The finding, reported by ForGeeks and picked up on the Hacker News front page, covers a buildout period that accelerated as generative AI demand took off.

The number is an estimate, not a census. According to the report, the federal government does not systematically track water consumption across the data-center industry, and much of the available information is gathered by state and local agencies. Some municipal agreements also restrict public disclosure of what individual operators pay and how much they draw. The 17-billion-gallon figure therefore covers more than water piped directly into server campuses, and it should be read as a national estimate rather than a facility-by-facility accounting.

Electricity is the bigger water cost

The CRS separates direct water use, such as on-site cooling, from the indirect use embedded in generating the electricity a facility consumes. Direct consumption is a relatively small slice of overall US water use — about 2% — while the report attributes more than 80% of a data center's total water footprint to power generation.

AI is pushing operators toward denser hardware deployments. New AI halls generally draw more electricity than older server infrastructure, which raises both their cooling requirements and the water consumed upstream by electricity production. Because the CRS data ends in 2023, before the AI buildout hit full stride, the report cautions that consumption may have climbed further since.

This framing also complicates claims that a facility is "waterless." A campus can avoid evaporative cooling on site, but if the replacement design is more power-hungry, part of the water burden shifts to the electricity supplier rather than disappearing.

Cooling choices trade water for power

Operators choose among several cooling approaches depending on a facility's size, location, climate and thermal requirements. Evaporation-based systems typically use less energy than air-cooled chillers and other waterless designs, but the water they lose to evaporation must be continually replaced. Air-cooled systems cut that direct demand while generally requiring more power. Liquid cooling can be more efficient than air cooling for high-density equipment, though the CRS notes it may not be cost-effective for smaller campuses.

Water can come from municipal drinking-water systems, treated wastewater, surface water or groundwater. Municipal supplies accounted for 97% of the water used by US data centers in the CRS estimate, placing data-center expansion in direct competition with other municipal and industrial demands, especially in regions with constrained supplies.

The tension has already reached the courts. A proposed 330 MW California data center is seeking 287 million gallons of water from fallowed farmland, a dispute now in litigation.

Fragmented data, slow legislation

Water provision is primarily a state-level responsibility in the US, and reporting requirements differ by jurisdiction. A federally supported effort led by Virginia Tech researchers, the United States Water Withdrawals Database, compiles reported and estimated withdrawals across 42 states, but its coverage depends on each state's reporting obligations, so it stops short of a uniform national registry.

Water-service agreements add another layer of opacity, since contracts between operators and municipalities can include provisions limiting public release of usage details. Without facility-level figures, the report argues, communities struggle to compare a proposed campus's water needs with its promised economic or infrastructure benefits.

Legislation is moving slowly. Members of Congress have introduced bills that would improve water-use reporting, encourage reuse and address other environmental effects of data-center construction, but most remain at the introduction stage, the CRS says. According to the campaign site Data Center Water Leaks, cited in the coverage, water-related data-center bills have appeared in 36 of 52 state legislatures, California and Arkansas vetoed local bills, and 20 federal bills — 14 in the House and six in the Senate — were active, with only three progressing beyond referral.

The European Union is further along: recent EU legislation requires operators to report annual freshwater consumption alongside other facility metrics. Industry group CISPE has warned that strict water rules could push infrastructure outside the bloc, and the European Commission has faced lobbying over a proposed environmental rating system covering energy and water efficiency.

Why it matters

Water is becoming a hard constraint on cloud and AI infrastructure, alongside electricity. The CRS numbers show the industry's footprint is dominated not by cooling towers but by power generation, so efficiency gains on site can simply relocate the problem rather than shrink it. For cloud customers and AI developers, this matters twice over: sustainability claims rest on data that does not exist in consistent form, and the communities weighing new campuses lack the facility-level figures needed to negotiate. Until the US adopts uniform reporting rules, as the EU has begun to do, the sector's true consumption will remain a national estimate stitched together from incomplete state data, while local conflicts over it multiply.