Gatwick expansion under judicial review this week
Cornerstone climate, Public law & judicial review, Planning & environment
The Government’s decision to grant a Development Consent Order (‘DCO’) for the expansion of Gatwick Airport will be under scrutiny in the High Court this week in a four-day rolled-up judicial review hearing, beginning on Tuesday 20 January 2026.
Two Claimants – Communities Against Gatwick Noise Emissions (‘CAGNE’) and Peter Barclay – challenge the decision on a range of grounds relating to climate, noise, and economic impacts, the treatment of wastewater, and the interpretation of national aviation policy.
The proposed expansion would see Gatwick’s existing northern standby runway replaced with a new operational second runway and deliver additional infrastructure to increase passenger capacity to 80.2 million passengers per annum (‘mppa’) by 2047, an increase of approximately 13 mppa.
The CAGNE claim
The CAGNE claim involves six grounds, with the first four relating to the climate change impacts of the proposed development. They concern:
- Whether the Secretary of State reached an irrational conclusion on the effects of the proposed expansion on the climate, applying guidance from the Institute of Environmental Management and Assessment and the government’s own Airports National Policy Statement (‘ANPS’).
- Whether she breached her obligations under the Environmental Impact Regulations 2017 by failing to assess the significance of the CO2 emissions from inbound international flights.
- Whether she breached her obligations under the EIA Regulations by failing to assess the significance of the non-CO2 effects of the project on the climate.
- Her treatment of the delivery risks associated with the Government’s Jet Zero Strategy for decarbonising aviation by 2050 and her approach to updated modelling on proposed future mitigation measures.
CAGNE also argues that the decision by the Secretary of State to give likely significant noise effects of the project neutral weight in the planning balance was in breach of her obligation under the EIA Regulations to integrate information on significant environmental effects into her decision on whether to grant development consent. Finally, it argues that Requirement 31 of the DCO, concerning the treatment of wastewater from the expanded airport facilities, is unlawful because it does not properly control against the potential overloading of nearby public sewer infrastructure.
Mr Barclay’s claim also includes grounds on the interpretation of the ANPS and the assessment of the economic benefits of the proposed development.
Representation
CAGNE is represented by Estelle Dehon KC, Ruchi Parekh, and Lois Lane, together with Odette Chalaby of Landmark Chambers, instructed by Rowan Smith and Julia Eriksen at Leigh Day.
