Last checked: October 22, 2026

Data centers and water

Data centers use water in two ways: on site, mostly to cool servers, and indirectly, through the power plants that make their electricity. Most get their on-site water from a city or public water system, though some use recycled wastewater or their own wells. This overview covers how much they use, where it comes from, and the permits and new reporting laws that apply. If you're on a private well near a proposed site, start with Will a nearby data center affect my well? and what to test before it opens.

How much water do data centers use?

Nationally: Lawrence Berkeley National Laboratory's 2024 report to Congress estimates that U.S. data centers consumed about 66 billion liters (about 17 billion gallons) of water on site in 2023, mostly for cooling. Large hyperscale and colocation facilities made up 84% of that. The water consumed generating their electricity was nearly 800 billion liters (about 211 billion gallons), roughly 12 times the on-site figure.¹

One facility: use varies widely with size, cooling design and climate.² Some published reference points:

• The International Energy Agency estimates a 100-megawatt U.S. data center may directly consume about as much water per day as 2,600 households (cited by CRS).³
• MPR News, reporting on Minnesota, put a mid-sized data center at about 300,000 gallons a day, and hyperscale sites can use much more.⁴
• The New York Times reported that a data center like Meta's in Newton County, Georgia, typically uses about 500,000 gallons a day. The county water authority said it accounts for about 10% of the county's daily water use.⁵
• Google reports it consumed 10.9 billion gallons across its data centers and offices in 2025, up 34% from 2024. That includes 469 million gallons at The Dalles, Oregon.⁶

Consumption vs withdrawal: "consumption" is water that evaporates and isn't returned. In evaporative cooling, most of the water drawn is evaporated, and the rest leaves as wastewater ("blowdown").²³

Cooling: evaporative vs air and closed-loop

• Evaporative (water-cooled) systems, such as cooling towers and direct evaporative cooling, remove heat by evaporating water. They use more water but less electricity.²¹
• Air-cooled and closed-loop systems recirculate air or the same water and use little or no water on site, but they generally need more electricity. LBNL notes a real tradeoff: a low on-site water number isn't automatically better, because the extra electricity has its own water footprint at the power plant.¹
• Hybrid designs use outside air most of the year and add evaporative cooling only on hot days. LBNL says many hyperscale facilities use this approach.¹ Water use rises in the hottest hours and months.³

Example: the Project Blue data center near Tucson moved from a water-cooled design to closed-loop air cooling. The developer now estimates about 15,000–20,000 gallons a day once it's operating.⁷

Where the water comes from

• Public (municipal) water. CRS cites an estimate that public water systems supplied 97% of U.S. data centers' on-site water in 2025.³
• Reclaimed (recycled) wastewater. Loudoun Water in Virginia, the biggest data center market, started building reclaimed water lines for data center cooling in 2010 and delivered more than 750 million gallons of reclaimed water in 2025.⁸ In Memphis, Tennessee issued a state operating permit for a plant that will take up to 13.5 million gallons a day of treated city sewage and further treat it as cooling water for xAI, a TVA power plant and a Nucor steel mill. The state says this reduces use of water from the Memphis Sand Aquifer.⁹
• Groundwater from the data center's own wells. This is less common, but there are documented cases in Arizona, Louisiana, Utah and elsewhere. See the private wells page.³⁷
• Surface water. CRS says it hasn't found operating U.S. commercial data centers that draw directly from surface water.³

What water quality does cooling need?

Cooling systems need water that won't leave mineral scale, corrode metal or grow bacteria and biofilm. CRS notes that water from a regulated public water system generally works. Data centers that use groundwater or reclaimed water may need to pretreat it first.³ As water evaporates, minerals concentrate, so some water must be drained (blowdown) and replaced. Operators use chemical and mechanical treatment to recirculate it more times before draining, and cooling towers need a Legionella water management program. Details are in How data centers treat cooling water. How that water is tested (conductivity, corrosion coupons, Legionella) is covered in Data centers and water testing.

Permits and rules

Withdrawals (state and local). Congress has generally left water allocation to the states. A data center that pumps its own water is subject to state groundwater and surface-water law, and that varies widely.³ For example, Georgia requires an EPD permit above 100,000 gallons a day of groundwater.¹⁰ Minnesota requires a DNR permit above 10,000 gallons a day or 1 million a year.¹¹ In Texas, local groundwater conservation districts issue the permits.¹² More examples are on the private wells page, and a 13-state table of thresholds and where to search applications is in who regulates big groundwater pumpers.

Discharges (Clean Water Act). According to CRS, data centers most often send wastewater to a municipal treatment plant, which makes them "indirect dischargers" under EPA's National Pretreatment Program, mostly enforced by the local utility. A data center discharging directly to a river or stream would need its own NPDES permit. Construction can also require stormwater permits and, if wetlands or streams are filled, Section 404 permits.³

Reporting and disclosure laws (new).

• Utah (HB 76, effective July 1, 2026): new data centers over 10,000 sq ft that plan to use 75 acre-feet a year or more must report before construction and every year after. The state publishes each facility's annual withdrawal.¹³
• New Jersey (signed Aug. 27, 2026): operators must report peak daily water use, water sources and energy use to the Board of Public Utilities twice a year. Critics note limits on what can be released publicly.¹⁴
• Virginia (HB 496, approved April 2026): utilities that report water use to the state must list the potable and the reclaimed water they supply each month to data centers holding a state air permit, as separate totals.¹⁵
• Minnesota (2025): data centers planning over 100 million gallons a year of consumptive use go through a DNR pre-application review, and permits must consider water conservation technologies. The pre-application exchanges are nonpublic.¹⁶¹⁷

What isn't known

• Facility-level numbers. CRS says data center water use is hard to quantify comprehensively, and some water service agreements limit disclosure.³
• Future totals. LBNL gives 2028 scenarios, not a single forecast. It projects 60–124 billion liters of on-site use for hyperscale facilities alone.¹
• Local effects. These depend on local supply, other demands and timing (hot days, droughts), and understanding is still evolving.³

Frequently asked questions

Do data centers use drinking water? Most use water from public systems, which is treated to drinking water standards. Some use reclaimed wastewater instead, as in Loudoun County, Virginia, and the planned Memphis plant.³⁸⁹

Is the water used by a data center gone? The part that evaporates leaves the local system as vapor. The rest is usually discharged as wastewater to a treatment plant.²³

Is air cooling always better for water? It uses little water on site, but more electricity, and power plants use water too. LBNL says the tradeoff depends on the site.¹

Where can I see how much a specific data center uses? Check state reporting programs (Utah publishes annual reports; New Jersey reports go to the BPU), company sustainability reports, and local utility or council records.¹³¹⁴⁶

Related guides

• How to document your well before nearby construction or heavy pumping
• Who regulates big groundwater pumpers? Finding permit applications near you
• Will a nearby data center affect my well?
• How data centers treat cooling water
• Data centers and water testing
• Who regulates private wells?
• How a private well works