Comment

EIA and data centres: current practice and emerging trends

Demand for data centres across the UK continues to grow, and with it comes increasing interest in associated environmental impacts by decision makers, stakeholders and the general public. Below, we outline how expectations around Environmental Impact Assessment (EIA) are evolving - both in determining the need for EIA and in ensuring impacts and mitigation are robustly considered for emerging data centre proposals. Recent experience shows a shift towards expecting these impacts to be more clearly articulated and evidenced.

In January 2026, a planning application by Greystoke Land and Altrad UK for a 90MW data centre (and supporting uses) in Iver, Buckinghamshire was successfully challenged and it is anticipated that the planning consent will be quashed at a full hearing later this year. The challenge succeeded because the council unlawfully screened out EIA by relying on unsecured mitigation. However, the case also highlights wider concerns, including the failure to consider the scale and intensity of operational uses, cumulative effects, and the provision of adequate reasons. The extent to which these additional grounds influenced the outcome can only be understood once the High Court Judgment is available. This case is likely to influence both the need for EIA and the level of assessment that is required for EIA development.

The requirement for EIA will always depend upon:

• The sensitivities of the site and its surrounds;
• The scale of the data centre proposed (including consideration of supporting infrastructure, where justified); and
• Whether there are likely significant effects, including cumulative effects (especially with any existing and committed industrial uses in the local area).  

Careful definition of what constitutes the project, and clarity on the specific environmental impacts (as further discussed below) is essential and must be informed by sufficient information about the proposals.

Establishing sufficient information regarding proposed data centres can be challenging, either:

• At a time to ensure that the need for EIA can be robustly discounted, well ahead of planning submission; or
• When a data centre is proposed as part of a wider outline application (for example a general industrial, storage and distribution project).

We have identified some of the key considerations when navigating EIA for data centres:

• Power requirements – data centres have a large power demand and securing such power may not be known. There should be an understanding of total power demand (and likely ancillary infrastructure), responsibility for its implementation and any future consenting regime/s.
• Carbon emissions – the reduction of carbon emissions associated with the large power demand will be reliant upon the decarbonisation of the grid, currently aimed for by 2030. Some projects are facing delays and restrictions in electricity supply, and alternative, short-term sources may require consideration.
• Water demand – data centres can require a large volume of water for cooling to remove heat from servers. There are alternatives such as air cooling, but these have a greater energy demand. Maximum water demand and mitigation should be estimated and considered, enabling the Environment Agency and water companies to consider cumulative effects.
• Plant noise – cooling plant (alongside backup generation) is likely to create noise which can create far more complaints from local residents than typical general industrial, storage and distribution noise. Where sensitive receptors are present, it is becoming increasingly challenging to identify impacts without consideration of data centre buildings and infrastructure layout.
• Air quality – the backup generation, usually diesel and their scale should be fully understood, alongside any requirement for flues. The backup generation will also require an environmental permit and potential testing.
• Traffic and Employment – both are likely to be far lower than traditional general industrial, storage and distribution. This is especially important to note where provided as part of options for a wider application.
• Outline Applications – where data centres are proposed in outline, careful consideration is required during the preparation of parameter plans to ensure that flexibility is achieved but not to an extent where a more intense operational use could be implemented without having been duly tested and reported in the Environmental Statement.

There are of course other impacts to landscape character, views and biodiversity - but these are generally well understood and less specific to data centre operation.

Summary

The likelihood that an EIA will be required for data centre projects will be dependent upon existing constraints, surrounding industrial uses and what actually constitutes the data centre project. The decision-maker has an important role in such conclusions.

There will be a requirement to understand a reasonable level of detail about the operation of the data centre in order to properly identify or assess likely significant effects. This is likely to include: energy demand and infrastructure; backup generation; cooling systems and water demand; and 24/7 operations. Where this is not known, assumptions can be defined.

All of this needs careful consideration and documentation as part of the project strategy stage. This should inform discussions and agreement with the decision-maker, supporting a more predictable and defensible EIA process.

We regularly support the delivery of EIA for data centres, with extensive experience supporting both standalone projects and schemes forming part of a wider development. Find out more about our Data Centres experience here.

For any project strategy advice on navigating EIA for data centres please contact Andy Ricketts or Andrew Malcomson.

11 June 2026