Residents near Dublin airport take  legal challenge over scrapping of 32 million passenger cap

Legal challenge — taken by the St Margaret’s/The Ward residents was brought before Justice Richard Humphreys on Monday at the High Court.

Dublin Airport administrator Daa faces legal proceedings calling for its 32 million person passenger cap to be enforced, one day before a bill aimed at scrapping the cap is to be brought before the Oireachtas.

The legal challenge — taken by the St Margaret’s/The Ward residents’ (SMTW) grouping under Section 160 of the Planning and Development Act 2024 — was brought before Justice Richard Humphreys on Monday at the High Court.

The case calls for the 32 million passenger cap — a provision inserted by the then An Bord Pleanála in 2007 as part of Dublin Airport’s planning application for its north runway — to be enforced immediately by Daa, a move which would see traffic at the airport dramatically curtailed.

Before Justice Humphreys, several interested parties, including Ryanair, Aer Lingus, and the Irish Aviation Authority (IAA) among others, declared their interest in being joined as notice parties to the case, applications to which SMTW have declared themselves not in favour.

Fingal County Council, which has been processing its own enforcement of the 32 million cap for just under two years while various other legal challenges involving Daa worked their way through the courts, also appeared, but declined to apply for notice party status, describing itself as “neutral” in the matter.

Justice Humphreys gave the parties two weeks to come to an arrangement regarding what entities, if any, should be allowed to be joined as notice parties before any trial proceeds.

Allowing other parties to join a legal action would likely increase legal costs for all involved precipitously, unless a judge were to protect any of the parties from such costs.

The action comes at a crucial time for the Government, which is set to introduce its own bill aimed at quashing the 32 million cap on Tuesday.

That bill, if enacted, would give transport minister Darragh O’Brien the power to remove or amend any planning conditions which, in the Government’s opinion, jeopardise the flow of international transport traffic in and out of Ireland.

Assuming the bill passes into law via the Oireachtas, the passenger cap would be unlikely to be removed before 2027 at the earliest. Various procedural steps, such as environmental assessments, would need to be taken by An Coimisiun Pleanála before any final action could be taken.

The timing is particularly relevant for the legislation being introduced, given it would effectively be in opposition to a live legal action which has yet to be decided.

Addressing the judge, barrister for Daa and former attorney general Paul Gallagher SC described “the seriousness of the relief” being sought, and said the action had been taken in a “casual” manner, allegedly “without setting out the full facts”, behaviour which he described as “very concerning”.

SMTW declined to comment on the case or whether or not it would be willing for notice parties to be joined to the case as respondents.

Daa had for some time insisted the airport had not been in breach of the 32 million cap, with critics, including SMTW, likewise insisting it had been.

However, more recently, the administrator has acknowledged the cap had been breached, noting  a record 36.4 million people had passed through Dublin Airport in 2025.