Summary

• Sien Real plans four datacentre buildings on a 45,305-square-metre site between Piaseczno and Józefosław.
• Budimex says expected water use would be comparable with a housing development for up to 3,000 people, while the project’s compute capacity remains undisclosed.
• Water scrutiny around datacentres predates the AI infrastructure boom, but denser compute is making local utilities a larger part of European site planning.

A four-building datacentre proposed outside Warsaw is facing local opposition over water demand, placing the physical requirements of digital infrastructure inside a municipal network that residents already regard as constrained.

The scheme is being developed by Sien Real, a joint venture formed by Polish construction group Budimex and Spain’s Ferrovial, on a 45,305-square-metre site between Piaseczno and Józefosław. Construction is expected to begin in 2027, although no public figure has been provided for the computing capacity of the proposed facility.

Budimex has said the site’s expected water use would be comparable with a housing estate serving as many as 3,000 people. Residents have raised concerns that the additional load could exacerbate existing pressure in Józefosław, where complaints about low water pressure have already accompanied continuing residential development.

Budimex spokesperson Marcin Graczyk said: “We are paying particular attention to minimizing the investment’s impact on local residents.” The developer says technical systems will be designed to reduce water consumption, noise and dust, although the detailed operating profile will be needed before those measures can be assessed against actual demand.

Cooling design changes the water calculation

Datacentres do not have a single water-use profile because cooling technology, climate and workload density can produce substantially different requirements. Some designs rely heavily on evaporative cooling, while others use closed-loop or predominantly air-based systems, and water can also be consumed indirectly through the electricity generation supporting a facility.

The Warsaw proposal therefore cannot be judged reliably by importing consumption figures from unrelated campuses. Its own design needs to show how much potable water would be required during normal operation, how demand changes during hot periods and whether the facility can reduce consumption when the municipal network is under stress.

Planning material from 2024 shows the site would also contain four 320-cubic-metre diesel tanks and 49 backup generators rated at up to 2,420kW each, while a 1,102-cubic-metre retention reservoir is planned for rainwater and snowmelt. Those figures describe resilience and site infrastructure rather than the undisclosed IT load, so they should not be treated as a proxy for the amount of compute the project will eventually contain.

Residents are consequently debating an industrial development whose resource footprint is partly visible but whose commercial scale remains unclear. Greater disclosure of the proposed IT capacity and cooling architecture would make it easier to judge the relationship between economic activity, utility consumption and the mitigation measures being promised.

Water pressure is an established planning risk

Concerns around datacentre water consumption are not a consequence invented by the current AI cycle. Large facilities have faced similar scrutiny in several markets for years, and operators have responded with air cooling, reclaimed water, closed-loop systems and designs intended to reduce potable-water demand.

AI can add pressure because higher-density hardware produces greater quantities of heat, although the effect on local water use depends on how a particular facility removes that heat. The more immediate planning issue around Warsaw is that any new industrial consumer has to operate within the capabilities of an existing municipal network rather than within an abstract national calculation of available water.

Local consent has consequently become part of datacentre development alongside electricity connections and fibre. Construction jobs and taxes can strengthen a proposal, but residents are more likely to scrutinise large resource users when utility limitations already affect ordinary homes and businesses.

Warsaw remains Poland’s largest datacentre market, and expansion around the capital is likely to continue as cloud and enterprise infrastructure spreads through central Europe. The Piaseczno project shows how that growth can become constrained at a much smaller scale: not by whether customers want more compute, but by whether a local network can supply the resources a particular building needs without degrading services around it.