Data center water and energy reporting laws in the US
Three states now make data centers report water use. New Jersey wants total and peak daily water input with energy use, with first reports due 27 November 2026 for established sites. California ties water reporting to business licenses, and Virginia adds disclosure from 1 January 2027. Each asks for metered numbers, which Aqueduct supplies per source and per cooling system.
Who it applies to
New Jersey covers any facility whose main business is storing and processing digital data, with no size threshold. Hospital data rooms are excluded unless they host unaffiliated customers.
California works by stage: a water use estimate before a business license, actual use at each renewal, and from 1 January 2028 a water supply assessment and scarcity plan for new projects. Virginia's HB 496 follows on 1 January 2027.
What each law asks for, and the data behind it
Summaries from the sources below. Check the statute and agency guidance before filing.
| State and law | What it requires | When | Data Aqueduct supplies |
|---|---|---|---|
| New Jersey, P.L. 2026, c. 75 | Annual energy in kWh, IT energy at the UPS, total and peak daily water input in cubic meters, and each water source. | 27 November 2026 for sites operating a year by 27 August 2026, 27 February 2027 for the rest, then every six months. | Interval water meters per source, so the peak day is measured, plus UPS output meters. |
| New Jersey, sites with state incentives | Also PUE, WUE, energy reuse factor, renewable energy factor, average IT inlet air temperature and waste heat temperature. | With each report. | Ratios computed from the same meters on one clock, inlet temperature from rack sensors. |
| California AB 2619 | Expected water use, source and volumes given to the water supplier before a business license, then actual total and direct water use at each renewal. | At licensing and every renewal. | Annual totals split between cooling makeup, process and domestic lines. |
| California AB 2469 | A water supply assessment and a water scarcity plan with phased withdrawal cuts and reuse. | From 1 January 2028. | Measured demand by system, so each phase of cuts is planned against real use. |
| California AB 1577 | Annual reporting to the Energy Commission, including PUE, fuel burned by on-site generators and cooling system data. | Annually. | Energy balance by source and load, with generator run hours. |
| Virginia HB 496 | Disclosure of water used by data centers, and potable and reclaimed supply shown separately by water providers. | From 1 January 2027. | Potable and reclaimed inlets metered as separate lines. |
Why peak day and source split are the hard part
A monthly bill gives one total per account. It cannot show the largest single day or split a site fed by a main, a well and a reclaimed line. Cooling tower makeup swings with wet bulb temperature, so the peak day usually lands in a heat event.
Aqueduct models the site as a water balance: main supply equals cooling makeup, process, domestic use and unaccounted loss. Each source and major use has its own meter, and the peak day is reported with the weather and IT load behind it.
Why states are asking now
Electricity used by data centers worldwide in 2024, about 1.5% of global demand.
Source: IEA, Energy and AI (2025)Projected data center electricity use by 2030, more than double the 2024 level.
Source: IEA, Energy and AI (2025)Signed in California on 21 September 2026 covering data center water, electricity and land use.
Source: Office of the Governor of CaliforniaWhere this is going
New Jersey's Board of Public Utilities must publish each facility's water and energy figures within 30 days of a report, and the duty runs three years before the board decides whether to keep it. From late 2026, a site's water numbers will be public.
In Europe, a Commission draft seen by Bloomberg in May 2025 said minimum water performance standards for data centers would be proposed by the end of 2026.
Sources6 references cited on this page
- Day Pitney: New Jersey enacts energy and water reporting requirements for data centers
- Office of the Governor of California: data center laws signed 21 September 2026
- Mayer Brown: California's governor signs the nation's most comprehensive data center laws
- Association of Water Technologies: legislative update, 7 July 2026 (Virginia HB 496)
- IEA: Energy and AI, executive summary
- Data Center Knowledge: EU will work on setting water use caps for data centers
sites in 21 countries run on Aqueduct.
and 9 clinics in one of India’s top hospital chains.
US airport running water intelligence on Aqueduct.
of commercial real estate under Aqueduct.
FMCG manufacturing campus.
operations run on Aqueduct.
Related
Common questions
27 November 2026 for data centers that had operated for at least a year by 27 August 2026. Other covered facilities file by 27 February 2027, then every six months. Aqueduct keeps the daily water and energy figures each report draws on, separated by source through a live water balance.
Yes. Aqueduct divides metered site water by IT energy read at the UPS output for the same hours, giving liters per kWh. New Jersey asks incentive recipients for WUE next to PUE, and both ratios come from meters on one clock rather than from bills. More on data center operations.
Peak daily water input is the largest single day of water drawn into the site during the reporting period. A monthly bill cannot show it. Aqueduct totals every day from interval meter data and marks the peak, then checks it against weather and cooling load so a hidden leak is not reported as demand, using leak detection.
No. Aqueduct supplies the measured water and energy figures and exports them for the filing, and the operator submits to the Board of Public Utilities, the water supplier or the Energy Commission. Every figure stays traceable to a named meter. See the compliance library for other reporting rules.
See Aqueduct on your own facility.
Bring a site, a utility bill or a question. We will show you where the loss is.