Heathrow third runway plans face growing opposition

Proposals for a third runway at Heathrow Airport, a project that has been under consideration for years, are encountering substantial opposition. The expansion would require the demolition of villages including Harmondsworth, Sipson, and Longford, and would see the M25 motorway tunnelled beneath the new runway. A new terminal and rail link are also part of the airport's vision.

Political and Environmental Opposition

Read Next in London Travel News5 min read

Heathrow third runway opposed by London mayor over £9bn transport costs

Sadiq Khan and TfL warn expansion would add 60,000 daily car trips and halve noise respite for residents

Mayor of London Sadiq Khan and Transport for London have formally declared their opposition to the Heathrow expansion. This stance is reflected in the Draft London Plan (2026), which states that proposals for airport expansion should be refused unless unacceptable environmental, transport, and congestion impacts can be demonstrated. This contrasts with earlier indications of support from the Labour government, with former Chancellor Rachel Reeves having previously suggested a favourable view towards a third runway.

Impact on Local Villages and Environment

The planned third runway would occupy land north and west of the current airport footprint. This would lead to the complete destruction of the village of Longford, which contains seven listed buildings. Approximately half of Harmondsworth would also be demolished, though its Great Barn and ancient church would be preserved but situated close to the airport's perimeter fence. Much of Sipson would be destroyed, with the remainder located at the end of the runway. The village of Colnbrook, while not demolished, would be at the other end of the runway, facing noise and pollution concerns. The expansion would also involve covering five rivers and compromising the Colne Valley Regional Park. Harmondsworth Moor, a nature refuge containing fragments of the Old Waterloo Bridge, would also be lost.

Related Borough Coverage3 min read

Heathrow expansion could revive Elizabeth line to Staines

London Assembly committee raises concerns over Piccadilly line crowding and Elizabeth line demand.

Arguments for and Against Expansion

Airport bosses and business groups argue that a larger Heathrow would boost economic growth through increased connectivity, trade, and job creation, with Heathrow Airport stating the project could create over 100,000 jobs nationally and be privately funded. They also contend that expansion is necessary for London to remain competitive with other major European cities. Conversely, opponents cite significant increases in noise and greenhouse gas pollution, as well as environmental damage during construction. Some airlines have also expressed concerns about the project's viability due to its cost.

Alternative Proposals

Various alternatives to the current expansion plans have been suggested. These include expanding Heathrow's existing runways to the west, developing other airports like Gatwick, increasing capacity through larger aircraft or more efficient operations, or building a new airport in the Thames Estuary. Opponents advocate for not expanding at all, arguing that the environmental and social costs outweigh potential economic benefits and suggesting a focus on encouraging reduced flying.

Next Steps

The Draft London Plan (2026) provides a clear indication of the current policy direction regarding airport expansion. Future decisions will likely depend on the demonstration of managed environmental impacts, as stipulated in the plan. The formal opposition from the Mayor of London and Transport for London signals continued political challenges for Heathrow Airport's expansion ambitions.