The Wall Street Journal published an investigation on July 3, 2026, reporting that AI data centers consume far more water than most major technology companies publicly acknowledge. The reporting targets the gap between the industry’s sustainability disclosures and the actual water draw of the facilities powering the AI boom — a gap with direct consequences for the communities, utilities, and regulators hosting these sites.
Executive Summary
According to the Journal’s headline finding, the water consumed by AI data centers substantially exceeds the figures most tech giants report. That claim lands at a sensitive moment: hyperscale operators are racing to build AI capacity at unprecedented scale, and many of the fastest-growing markets for that capacity are in water-stressed regions where every megawatt of cooling has a hydrological cost.
The significance is less about any single number and more about trust in the measurement system itself. Data center operators have spent a decade building sustainability reporting frameworks — water usage effectiveness metrics, replenishment pledges, “water positive” targets. An investigation asserting that disclosed figures materially understate real consumption challenges the credibility of that entire apparatus, and will sharpen scrutiny from permitting authorities, investors, and enterprise customers alike. It is worth noting up front that the material available at publication is the Journal’s headline claim; the underlying methodology and company-by-company figures sit behind the investigation itself, so our analysis focuses on how such a gap can exist and what it would mean if borne out.
Why Water Is the AI Boom’s Quiet Constraint
Data centers use water primarily for cooling. Evaporative systems — the most energy-efficient way to reject heat in many climates — work by evaporating water to carry heat out of the building, which means the water is genuinely consumed rather than borrowed and returned. AI workloads intensify this: training and inference clusters pack far more power into each rack than traditional enterprise computing, and every kilowatt of electricity ultimately becomes heat that must go somewhere.
Power availability has dominated the AI infrastructure conversation, but water is the constraint that most directly touches neighbors. A community can rarely see the grid strain a campus causes; it can see reservoir levels, well permits, and municipal supply contracts. That visibility is why water — more than carbon — has become the flashpoint in local data center opposition, and why a disclosure gap, if substantiated, matters commercially and not just reputationally.
How a Disclosure Gap Can Exist Without Anyone Lying
Water accounting has honest ambiguities that reporting can exploit or obscure. “Withdrawal” (water taken in) and “consumption” (water evaporated and lost) are different numbers. On-site cooling water is different from the much larger volumes evaporated at the power plants generating a facility’s electricity — a burden that rarely appears in corporate water figures. Companies may report global averages that dilute stress in specific basins, disclose only company-owned sites while leasing heavily from colocation providers, or treat site-level data as a trade secret in agreements with local utilities.
Each choice can be individually defensible and collectively misleading. If the Journal’s investigation shows real draw far above disclosed figures, the likeliest mechanism is not fabrication but selective scope: what gets counted, where, and at what level of aggregation. That is precisely why the methodology on both sides deserves scrutiny — an investigation comparing utility records of total withdrawal against corporate disclosures of net consumption would find a large gap even where reporting is technically accurate. Neither the companies’ frameworks nor the investigation’s comparisons should be taken on trust without seeing definitions aligned.
Winners, Losers, and the Coming Transparency Squeeze
If disclosure practices tighten — voluntarily or by mandate — the advantage shifts to operators who engineered for water frugality before it was scrutinized: closed-loop liquid cooling, dry coolers, air-side economization in suitable climates, and treated wastewater sourcing. Vendors of direct-to-chip and immersion cooling gain a stronger sales narrative, since liquid cooling at the rack can pair with water-free heat rejection outside. Operators dependent on open evaporative cooling in arid, fast-growing markets face the hardest repricing, because retrofits are costly and permitting timelines are long.
Enterprise buyers and investors are the other lever. Cloud and colocation contracts increasingly carry sustainability reporting clauses, and a credible investigation gives procurement teams grounds to demand site-level water data rather than glossy aggregates. For host communities, the practical effect is likely to be harder-edged development agreements: metered disclosure requirements, drought curtailment provisions, and consumption caps as conditions of approval. The industry can resist that trend or get ahead of it; the second option is cheaper.
Background
Water has trailed energy as the second axis of data center sustainability for over a decade. Major operators publish water metrics alongside “water positive” replenishment pledges — commitments to restore more water to stressed basins than their operations consume. Those frameworks were designed in the era of conventional cloud computing; the AI buildout that accelerated from 2023 onward brought far denser facilities, faster construction, and expansion into hot, dry regions where land and power are cheap but water is contested.
Local friction has grown in step. Communities from the American Southwest to Europe and Latin America have challenged data center water allocations, and operators have responded with a mix of reclaimed-water sourcing, liquid cooling adoption, and — critics argue — selective disclosure. The Journal’s investigation lands squarely on that last point, testing whether the industry’s reported numbers describe the facilities actually being built.
Amazon says the buildings that run its websites, apps and artificial intelligence services use about one-seventh the water of a typical facility of their kind.
The main trick is letting the computers run warmer. Outside air cools the buildings about 90% of the time. Water is used only when it is hotter than about 85 degrees Fahrenheit outside.
This matters because these buildings are multiplying, and their neighbors want to know how much local water they take. The open question is whether the newest artificial intelligence chips, which Amazon says needed a new kind of liquid cooling, will let that approach last.
Amazon said in a June 11, 2026 post on its About Amazon site that its global data center operations used 0.12 liters of water per kilowatt-hour (L/kWh) in 2025. The company puts that at more than seven times better than an industry average of 0.84 L/kWh and says it is a 52% improvement since 2021. It withdrew about 2.5 billion gallons of water across its global data center footprint in 2025.
Amazon credits two things for the result. The first is free-air cooling, which it uses about 90% of the time. The second is higher server temperature limits, so that evaporative cooling runs only when outside air is above roughly 85°F. The company also said it is 75% of the way to its 2030 water-positive goal and that it runs 26 facilities on 100% reclaimed water, with 130 more contracted.
Executive Summary
Amazon has published a headline water-efficiency figure for its data centers: 0.12 liters of water for every kilowatt-hour of energy in 2025. It set that against an industry average of 0.84. The company explains how it got there. It relies on outside air for most cooling, uses evaporative cooling only in the hottest hours, and has spent several years raising the temperatures its servers are allowed to run at. It says this cut water use without raising hardware failure rates.
The figure matters because water has become one of the main local questions asked of new data center campuses. Amazon’s explanation also shows that water efficiency is a set of engineering trade-offs, not a fixed property of a building. The company chose to use some water on hot days rather than run chillers, which it says need 25% to 35% more electricity at the moments the grid is most stressed.
Two things are harder to assess. One is the comparison itself: Amazon did not publish how the 0.84 average was built or on what basis each peer’s figure is measured. The other is the future. Amazon says denser AI chips already required a custom liquid cooling system, so the air-first approach behind the 7x figure now has to hold up as AI capacity grows.
The Water Number Is Really a Temperature Number
Amazon’s 0.12 liters per kilowatt-hour did not come from a new water technology. It came from deciding how rarely to use water at all. About 90% of the time, Amazon says, its data centers use free-air cooling. Outside air is drawn past the servers and pushed back out, with no water involved. Water comes into play only through evaporative cooling. In that process, hot air passes through a water-soaked medium and cools by five to 10 degrees as the water evaporates. Amazon now switches that on only when outside air exceeds roughly 85°F.
That threshold is the lever. Every degree of heat the servers can tolerate removes hours from the evaporative season, so raising operating temperatures cuts water use directly. Amazon’s own evidence is specific:
Two identical data centers on the same campus, one running hotter, differed by about 50% in water use.
Northern Virginia, its largest region by IT load (the power drawn by the computing equipment itself), cut water use 42% year over year while demand grew.
Thousands of hours of campus data showed no increase in failure rates at the higher temperatures.
Those results fit the 52% efficiency improvement Amazon reports since 2021.
The same logic is why this is a test for AI-era cooling. The approach depends on air being able to carry heat away from the servers. Amazon itself says denser, more powerful AI chips required a completely custom liquid cooling system. It has not said how much of its fleet now runs that way, whether those systems rely on evaporative water on hot days, or how a growing share of AI capacity will move the 0.12 figure. The air-first playbook behind the 7x gap was proven on the fleet Amazon has run since 2021. Whether it carries over to high-density AI halls is the next data point to watch.
Water or Watts: The Trade Behind the Ratio
Amazon is explicit that a low water number is partly a choice about electricity. The alternative it names is chillers, which work like giant air conditioners and, by Amazon’s figures, typically need 25% to 35% more electricity. The timing of that extra load is the problem. It arrives in the hottest hours, when household air conditioning is already straining the grid. Amazon concluded it is better to spend some water on those days than to add power demand at the peak.
That is a defensible engineering position, and it cuts against a simple reading of water metrics. An operator could report a lower water ratio by running chillers, which shifts the burden onto the grid and, depending on how that electricity is generated, onto water used off site. Conversely, a site that uses more water may be sparing a stressed grid. For utilities and local planners, the useful question is how much water and how much power a campus uses together at the peak hour, not either one in isolation.
Amazon did not quantify the grid side of its trade. It has not said how much peak demand evaporative cooling avoids across its fleet, or how many hours a year its sites in hot regions exceed 85°F. Without those figures, the argument rests on the chiller penalty range alone.
Why 0.12 and 0.84 Are Hard to Line Up
Liters per kilowatt-hour is the industry’s standard water-efficiency ratio, often called water usage effectiveness. It divides the water used for cooling by the energy consumed by the IT equipment. Amazon describes it as water per unit of compute, but the denominator is energy, not work done. A fleet running more efficient chips gets more computing out of each kilowatt-hour, and the metric does not capture that in either direction.
The 7x claim depends entirely on the 0.84 industry average. Amazon’s chart cites sustainability reports and blogs from Microsoft, Google and Meta alongside its own report. The company did not publish how 0.84 was derived: which operators it covers, how they were weighted, or whether each figure measures water withdrawn (taken from a source) or water consumed (evaporated and not returned). Large operators do not all report water the same way, so a like-for-like reading requires knowing which basis each number uses.
Scope matters too. Amazon’s absolute figure, about 2.5 billion gallons in 2025, is a withdrawal number for its global data center footprint. The 2% year-over-year decline it cites applies only to sites it owns and operates directly. The company did not say whether the 0.12 ratio is based on withdrawal or consumption, or whether leased facilities are included. None of that makes the claim wrong. It does mean the 7x multiple is Amazon’s own calculation rather than a figure a reader can reproduce from peers’ reports.
Replenishment and Reclaimed Water Carry the Local Story
Efficiency is only half of Amazon’s water case. The company has committed to being water positive by 2030, meaning it returns more water to communities than its data center operations use. It says it is 75% of the way there, returning 3 gallons for every 4 used in 2025. It has announced more than 50 projects that are expected to return over 5.8 billion gallons a year once fully implemented, which is more than twice its 2025 withdrawals. Examples include:
storing Columbia River winter flows in an aquifer in Hermiston, Oregon;
a runoff pipeline in Pina del Ebro, Spain;
watershed restoration near Guadalajara, Mexico.
Replenishment is an accounting balance. Its value to a given town depends on whether the returned water lands in the same basin the data center draws from. Reclaimed water addresses the local question more directly, because it replaces drinking water with treated wastewater at the site itself. Amazon says 26 facilities already run on 100% reclaimed water, more than any other cloud provider, and 130 more are contracted. It has also funded infrastructure and helped with permitting for programs in Mississippi, Hong Kong and Indonesia. If those 130 facilities come online, reclaimed supply may matter as much to neighbors as the headline efficiency ratio.
Background
Amazon operates one of the world’s largest data center fleets, mostly to run Amazon Web Services (AWS), its cloud computing business. Data centers convert nearly all the electricity they use into heat, and removing that heat is where most of their water goes. The industry commonly measures water efficiency as liters of water per kilowatt-hour of IT energy, a ratio known as water usage effectiveness, or WUE.
Amazon has committed to being water positive by 2030 and has expanded its use of reclaimed water from wastewater treatment plants. Amazon says data centers account for less than 0.5% of global industrial water use. Still, where a campus draws its water matters to the surrounding community, and Amazon says its water team is particularly focused on water-scarce areas.
