A colossal white elephant: Government selects most disruptive and costly option for Heathrow expansion

26th November, 2025

On Tuesday 25th of November, the Government announced its selection of Heathrow Airport Limited’s (HAL) proposal as the basis for progressing plans for the third runway project. If approved, this scheme will require thousands of homes to be either demolished or left uninhabitable, as well as the complex re-routing of the M25 motorway through a new tunnel system.

AEF opposes any expansion at Heathrow Airport on grounds of negative community impact, increased noise for people living in London and Berkshire, unsubstantiated economic claims, and incompatibility with climate budgets and targets. The Government’s choice of the most expensive and disruptive option raises serious questions about its strategy and priorities. This expansion plan – requiring the purchase and destruction of thousands of homes and extensive M25 infrastructure work – risks becoming mired in the same delays and cost overruns that plagued HS2, while simultaneously failing to deliver the claimed economic growth. It is likely to lead to years of delay and congestion on key junctions of the country’s busiest motorway, and there’s likely to be industry pressure from the outset for the Government to commit billions in public money on improving transport links.

Departures versus arrivals: a key economic distinction 

Recent studies have challenged the economic claims made by airports regarding growth and job creation. The UK currently experiences a net tourism deficit of over £41bn, with more British residents flying abroad for holidays than international tourists arriving. With business travel demand in 2023 down by nearly a third compared with pre-pandemic levels as corporations embrace remote working and reduce air travel, the claimed economic benefits appear increasingly questionable. It seems likely that the expansion will facilitate an increase in outbound leisure travel, rather than generate meaningful business investment.

Even the Government’s own statement inadvertently acknowledges this flow out of the UK, emphasising that London’s airspace redesign will “ensure the capital’s skies are ready for more departures from a third runway from 2035.”

Time and time again, the Government seems determined to prioritise dubious claims of economic benefits over nature and communities. With these economic arguments increasingly showing cracks, it is impossible to justify this poorly-judged expansion,” says AEF.

Community health costs ignored

This expansion imposes significant economic costs on local communities through increased air and noise pollution. The negative health impacts of air pollution are well known and are estimated to represent millions of pounds in healthcare each year and can be linked to serious health impacts. Recent research has shown exposure to early morning and night-time noise – something communities under the Heathrow flightpath experience daily with flights arriving from 4.30am – has been linked to an increased risk of major cardiac events, such as a heart attack.

Cost-benefit assessments have consistently undervalued community health and environmental costs. Back in 2018 when Heathrow expansion was last on the table, inclusion of climate costs wiped out all the claimed economic benefits of the project,” says AEF. 

The next step of the process will see the Department of Transport review the Airports National Policy Statement, something it hopes to complete by the end of 2026. This is an opportunity to gather and publish important data to help ensure that the serious environmental and economic arguments against expansion are addressed in a transparent way.