Summary
- A Virginia groundwater study modelled withdrawals of three million gallons a day in each groundwater-budget region.
- A modelled 100MW hyperscale facility could use about 300,000 gallons daily, depending on cooling design.
- State senators are seeking further scrutiny, with some supporting a temporary moratorium on new development.
Virginia lawmakers are seeking urgent action on groundwater demand after a state study examined the potential effect of new industries, including data centres, on the Commonwealth’s water resources.
Republican state senator Richard Stuart and Democratic senator Russet Perry have asked the governor to call a special legislative session, arguing that groundwater supplies are under immediate pressure and that lawmakers did not have an opportunity to consider the report before the annual session ended.
The study by the Virginia Department of Environmental Quality modelled a withdrawal of three million gallons a day at the centre of each groundwater-budget region. That figure was a planning scenario rather than a measurement of every existing data centre.
The report estimated that a typical 100MW hyperscale facility could require about 300,000 gallons of water a day. At approximately 1GW of IT load and 31.6m square feet of floor area, the modelled demand rises to roughly three million gallons a day.
Actual consumption varies widely. Cooling-system design, local climate, operating temperature, workload, water source, and the use of reclaimed water all affect withdrawal and consumption.
Older evaporative systems can use substantial volumes of water to reject heat. Closed-loop designs recirculate water and can reduce routine withdrawals, although they may carry higher electrical demand or require larger dry coolers during hot conditions.
Several Virginia facilities use treated wastewater rather than potable or groundwater supplies. That approach can reduce competition with domestic users but still depends on pipelines, treatment capacity, water quality, and agreements with local utilities.
Water joins power in the planning debate
The groundwater review has widened into a broader argument over the pace of data centre development. Republican senator Glen Sturtevant has separately called for an immediate statewide moratorium on new projects, while Democratic senate president pro tempore Louise Lucas has said the proposal deserves serious consideration.
Virginia contains the world’s largest concentration of data centres. The state has approximately 11GW of operational capacity, while Loudoun County alone contains about 200 facilities.
The scale has made data centres a central part of electricity, land-use, transmission, and tax policy. Groundwater adds another infrastructure system that local authorities must assess before approving further campuses.
Water demand can be less visible than power demand because it changes by season and operating mode. A facility may draw relatively little water during mild periods but require more during hot weather, when public supplies and ecosystems are already under pressure.
Planning based only on annual averages can therefore understate peak stress. Authorities need information on maximum daily withdrawal, source, discharge, cooling technology, drought operation, and the circumstances in which backup water arrangements would be used.
A moratorium would not resolve those technical questions by itself. It could create time to establish statewide standards, but it would also delay projects with low-water designs or access to non-potable supplies unless exemptions were carefully structured.
The Virginia debate provides a comparator for European regions experiencing rapid data centre growth. Water availability is already a planning consideration in parts of Spain, the Netherlands, Ireland, and the UK, even where developers emphasise closed-loop cooling.
AI hardware complicates the calculation. Higher rack densities increase the amount of heat that must be removed from a smaller area, encouraging liquid cooling at the server while leaving a separate decision about how heat is ultimately rejected from the facility.
Direct-to-chip liquid cooling does not automatically eliminate water consumption. The facility may still use evaporative towers, hybrid coolers, or dry cooling at the external heat-rejection stage.
Virginia’s report places those engineering choices inside a public-resource question. The issue is not whether every data centre consumes the same amount of water, but whether planning authorities have enough verified information to distinguish between designs and understand their combined effect.
The proposed special session and moratorium calls indicate that assurances alone are no longer sufficient. Future projects may be required to demonstrate water performance, source resilience, and drought behaviour with the same detail now expected for grid demand and backup generation.
