One day before Senators Hawley and Warren sent their joint letter to the Energy Information Administration demanding mandatory energy reporting for data centers, Senator Dick Durbin introduced his own bill. The Data Center Water and Energy Transparency Act, filed March 25, goes further than the Hawley-Warren ask in two directions: it adds water consumption to the disclosure requirement, and it mandates reporting to state governments rather than a single federal agency.
The legislative calendar matters here. Hawley and Warren asked the EIA to respond by April 9. Durbin's bill is moving through the Senate on a separate track. Together, they represent the most concentrated legislative pressure the industry has faced on transparency, and they arrived within 24 hours of each other.
The Durbin bill has three operative requirements. First, existing data center operators must report both energy and water consumption quantities to the states where they operate. The reporting cadence is not specified in Durbin's press release as annual or monthly, but the bill requires actual consumption figures, not estimates derived from nameplate capacity or utilization assumptions.
Second, operators proposing new facilities must disclose five-year projected energy and water consumption before construction. Local governments and utilities considering new data center siting would have access to those projections. This is the part of the bill that will generate the most friction: requiring operators to commit to five-year consumption forecasts creates a disclosure they may be held to by local planning boards, environmental groups, and utility regulators.
Third, the EPA, Department of Energy, and USDA would jointly receive aggregated data from across all reporting facilities and publish regional reports. Those agencies would be authorized to impose fines on noncompliant operators. The fine authority is the mechanism that distinguishes this from voluntary disclosure programs the industry already runs through groups like the Green Grid.
Durbin's office cited that a 100 MW data center consumes as much water as approximately 2,600 households. At current build rates, with 550 planned projects representing 125 GW of total global capacity in the pipeline, that figure compounds. US data centers could require 697 million to 1.45 billion gallons of additional peak water capacity per day by 2030 — bracketing New York City's entire daily water supply on the high end.
The Hawley-Warren letter asks for electricity data, which is metered at every facility already. Water is different. WUE calculations depend on facility boundary definitions, what counts as consumptive use versus water that returns to the watershed, and how supplemental evaporative cooling during peak summer conditions gets accounted for. A facility running closed-loop direct-to-chip cooling for 11 months of the year but cycling on evaporative cooling towers during a two-week heat event has to decide what its annual water figure actually is.
The industry has not converged on a methodology. The Green Grid's WUE specification exists, but uptake across the full operator population is uneven and the annualization methods vary. A federal or multi-state reporting mandate would impose a single definition. That is useful for regulators and a compliance problem for operators who have been calculating WUE however their internal teams chose to do it.
The operators who will navigate this most cleanly are running liquid cooling architectures with closed-loop designs that produce minimal evaporative loss. A facility running direct-to-chip cooling with a closed-loop CDU and dry coolers for heat rejection has a low and auditable WUE. A facility running hybrid air-cooling with open evaporative towers has a number that varies by season, climate, and utilization. When that number goes into a state database, it will be visible to every local government, water utility, and environmental group in the jurisdiction.
Durbin's framing of state-level reporting is politically shrewd and practically significant. The Hawley-Warren letter is directed at a federal agency. Durbin's bill routes data to the states where data centers actually operate. That puts the reported numbers directly in front of the planning boards, legislators, and water utilities who are already dealing with the consequences of rapid data center growth in their regions.
Virginia has already passed legislation requiring water utilities to report monthly volumes delivered to data centers. California's AB 1577 would require monthly reporting to the State Energy Commission. Pennsylvania's H.B. 1834 passed mandatory energy reporting. The state-level momentum is moving in the same direction as Durbin's federal bill. The operators who assume state reporting requirements will stay fragmented and inconsistent are likely to be wrong within 24 months.
The question the Durbin bill raises is whether the federal framework preempts the state patchwork or adds to it. If both pass in some form, an operator with facilities in Virginia, California, and Texas faces three separate reporting frameworks plus a federal one. That is the outcome nobody in the industry wants and nobody in Congress seems to be coordinating to prevent.
Mandatory water reporting changes the calculus on cooling architecture in a specific and immediate way: it makes low-WUE designs more defensible in regulatory and community relations contexts, independent of their operating economics.
An operator choosing between evaporative cooling, closed-loop liquid cooling, and zero-water approaches in a new facility already has an energy cost argument for liquid cooling. Under a mandatory reporting regime, they also have a reporting risk argument. Evaporative cooling at scale in a water-stressed region, disclosed publicly to state regulators every year, creates a regulatory surface area that closed-loop or zero-water designs do not.
Zero-water cooling pilots in Phoenix and Mt. Pleasant were motivated in part by exactly this dynamic. Phoenix operates under strict water restrictions. Mt. Pleasant is watching what Arizona is doing. The pilots that started as operational experiments are becoming the reference architecture for operators who expect to be reporting their water draw to state governments within two to three years.
Three bills, three Senate offices, one week. Hawley and Warren at the EIA. Durbin at the state level with EPA, DOE, and USDA backing. The Sanders-Ocasio-Cortez moratorium sitting as the most aggressive framing in the mix, unlikely to pass but useful as a ceiling for what "not passing" looks like.
The data center industry's standard response to regulatory pressure has been to argue for voluntary frameworks, note the economic contributions of the sector, and wait for legislative momentum to stall. That strategy worked through most of the 2010s and early 2020s. The grid load numbers from 2025 forward — 4.4% of US electricity today, EPRI projecting 9-17% by 2030, Bloom Energy projecting national demand nearly doubling from 80 GW to 150 GW by 2028 — have changed the political environment in a durable way.
The operators who shape what mandatory reporting looks like will have a better outcome than the ones who fight it. Durbin's bill has teeth: fine authority for noncompliance and state-level visibility into facility-specific consumption. The industry has until the first committee markup to propose a methodology that is rigorous, auditable, and operationally feasible. After that, the methodology gets set by staff who have never been inside a mechanical room.