A watchdog group has warned that proposed expansion of Luton Airport, lined up for approval, could pave the way for 23.5 million passengers being flown annually.

Campaigners throughout St Albans have, along with neighbouring areas, been fighting against the airport’s controversial scheme to double passenger numbers to 18 million a year.

And there are now fears that figure could end up being much higher.

The airport has asked Luton borough council (LBC), its owner, for approval to expand and allow an extra 160 flights a day.

LBC has received 455 objections to the scheme, and 43 in support.

Despite opposition, LBC’s development control committee has been recommended by officers to approve the scheme.

Although permission was expected to be granted at a meeting today (Thursday), on Tuesday the council announced the decision was being deferred while consultees’ comments were explored further.

But London Luton Airport Town and Villages Communities Committee (LLATVCC) has spoken out against the plan.

In a recent newsletter the group said members had read consultants’ reports to the council – one estimating the airport’s current capacity, and the second estimating what it might be should the scheme be approved.

The newsletter warned: “Our reading of the second report is that the likely capacity of the airport could be well in excess of 23.5 million passengers per year.”

The committee said that with the council’s independent consultant’s report showing a considerable increase in passenger numbers, the scheme should be treated as a “nationally significant infrastructure project” (NSIP).

The watchdog group has pointed out that, under the Planning Act 2008, a NSIP should be determined independently, by the Planning Inspectorate, rather than the council.

The newsletter added: “The text in the Planning Act is crystal clear: ‘is the proposal capable of increasing the capacity of the airport by more than 10 million passengers a year?’”

n The evaluation of a trial initiated by the airport to stop planes straying out of an official flight path and flying over homes in St Albans is still underway.

The trial was conducted in two phases earlier this year, and affects western departures flying routes via Clacton and Dover – a track designed over 20 years ago.