Proposals by Heathrow Airport to potentially increase the number of planes over Richmond Park each year could damage the area’s biodiversity, a City Hall politician has said.

Caroline Pidgeon, Lib Dem group leader on the London Assembly, has said that new flight path options suggested by Heathrow would also worsen noise pollution for nearby residents.

Heathrow said that no decisions have yet been taken on which flight path options will be taken forwards.

The proposals have been submitted by Heathrow as part of its ‘airspace modernisation’ plans – a Government initiative which aims to create “quicker, quieter and cleaner journeys, and more capacity for those using and affected by UK airspace”.

An analysis carried out by the Friends of Richmond Park found that under the current proposals – which remain at an early stage – as many as 60,000 arrival flights could pass over the park. As flight options are expected to be adjusted over the course of the airport seeking regulatory approval from the Civil Aviation Authority, that number could rise or fall significantly.

There are currently no arrival flights over the park, though a relatively small number of departure flights pass over the southern part of the park.

A motion put forward by Ms Pidgeon will be debated by the Assembly next week. If passed by members, it will state that the Assembly “notes with concern that Heathrow Airport did not include a Status Quo / Do Minimum option in its submission”.

It will also call on the CAA to reject the latest version of Heathrow’s plans, and will call on Heathrow “to go back to the drawing board and bring forward proposals that include a Status Quo / Do Minimum option and that protect Richmond Park and London’s communities from increased flight paths”.

A Heathrow spokesman said: “We have committed to play our part in the Government’s Airspace Modernisation Strategy and at this early stage of the process we have been required to explore all possible flight path options.

“No decisions have been made on which flight path options could be adopted or discarded from the recently published shortlist. These decisions will not be made until we have had a chance to undertake detailed environmental assessments and fully consult local communities.

“We encourage everyone with a view to submit their feedback when we reach that stage.”

The airport’s plans for a third runway are separate from the airspace modernisation proposals. The third runway plan has been paused since the pandemic, but Javier Echave, Heathrow’s chief financial officer, recently suggested that it could soon be looked at afresh.