No expansion until Heathrow sets out “concrete proposals” for environmental mitigation, warn MPs

House of Commons Environmental Audit Committee warns government not to grant go-ahead for Heathrow expansion until the operator sets out clear commitment to the Airports Commission conditions over noise, air pollution, transport and night flights.

MPs this week warned the government not to approve plans for a £18bn Heathrow Airport third runway expansion until the airport could “demonstrate that it accepts and will comply with the Airports Commission conditions” to mitigate local, environmental and health concerns. 

Failure to do so or to defer the implementation of such measures recommended by the recent Davies Commission would, said MPs on the House of Commons Environmental Audit Committee, increase the project risks through delay and potential “unquantifiable cost” increases.

“In each case - climate change, air quality and noise - it needs to set out concrete proposals for mitigation alongside clear responsibilities and milestones against which performance can be measured,” 

Environmental Audit Committee

Should the government not get sufficient assurances that appropriate mitigation was in place, the report highlights the option to not press forward with project.

“If the Government is minded to go ahead with the Commission’s recommendation, it is likely that this will be followed by a further period of consultation. The Government should use this period to address the recommendations in our report, before making a final decision on whether to go ahead with the scheme.”

Measures highlighted by the Committee’s latest report that should not be overlooked or deferred include a night flight ban, covering the costs of surface transport improvements, demonstrating that it can expand within legal air pollution limits, and that an expanded Heathrow would be less noisy than a two runway Heathrow. 

“In each case - climate change, air quality and noise - it needs to set out concrete proposals for mitigation alongside clear responsibilities and milestones against which performance can be measured,” said the report

“It should report regularly to Parliament, through this Committee and others, on progress.”

The MPs report comes ahead of the government’s long awaited ruling on plans to expand UK airport capacity in the South East. The independent Airports Commission, chaired by Sir Howard Davies, published its conclusion in July this year to recommend expansion at Heathrow.

“The Government must make a binding commitment that Heathrow will fund the infrastructure improvements necessary to accommodate an expanded Heathrow.” 

Environmental Audit Committee

In his report Davies said: “To make expansion possible the Commission recommends a comprehensive package of accompanying measures including a ban on night flights and a new noise levy to fund a far stronger and more generous set of compensation and mitigation schemes.”

The Environmental Audit Committee’s report this week warns government not to “avoid or defer” these issues. 

“To do so would increase the risks of the project: delay through legal challenge, unquantifiable costs resulting from unclear responsibilities, economic risks through constraint of other sectors to meet increased aviation emissions and long-term costs to public health from the impact of air pollution and noise,” said the report.

Before giving the go ahead to Heathrow expansion, MPs also urged government ot set out its assessment of likely infrastructure improvements, agreed responsibilities for funding and milestones for completion. 

“This should be part of a wider transport strategy for West London to minimise the risk of unintended consequences,” it says. “The Government must make a binding commitment that Heathrow will fund the infrastructure improvements necessary to accommodate an expanded Heathrow.”

MPs also urged government to do further work to clarify areas of dispute following the Davies Commisson’s work around forecasts of likely  operational and technological improvements that are still the subject of significant disagreement.

“We urge the Government to produce and publish its own thorough evaluation of the forecasts, including its assessment of whether take-up is likely to be sufficient without Government intervention’” it says.

Other recommendation made by the Committee include:

  • Before making any decision on Heathrow expansion, the Government should publish an assessment of the likely impact on the aviation industry - particularly regional airports - and wider economy of measures to mitigate the likely level of additional emissions from Heathrow.
  • We recommend that any Government decision on airport expansion should be accompanied by a package of measures to demonstrate a commitment to bringing emissions from international aviation within the economy-wide target set by the 2008 Act. 
  • Before the Government makes its decision, it should make its own assessment of the likely costs of preventing an adverse impact on health from expansion at Heathrow and publish it.
  • Before the Government makes its decision, it will need to demonstrate that its revised air quality strategy can deliver compliance with legal pollution limits within the timescales agreed in the finalised plan to be approved by the European Commission. It will also need to show that this can be maintained even when the expanded airport is operating at full capacity. Heathrow’s existing air quality strategy should also be revised to meet the new targets.
  • The Government must establish clearly delineated responsibilities for meeting air quality limits before deciding to go ahead with the scheme. We foresee significant legal and commercial risks further down the line if this is not done.
  • The Government, when assessing the noise impact of an expanded Heathrow, should do so against a full range of metrics and not just average noise experienced.
  • The Commission recommended the establishment of an Independent Aviation Noise Authority. This body will need a more up to date understanding of people’s attitudes to noise if it is to be credible.
  • The Government needs to demonstrate that, in assessing the case for expansion, it has based its decision on whether an expanded Heathrow would be noisier or less noisy than a two runway Heathrow at the same point in time - taking into account respite and the need for predicable relief from overflying. 
  • The Commission’s recommended ban on night flights was a key part of the package proposed by the Commission. The Government should publish a plan, including a series of binding milestones, to deliver the proposed ban as part of any announcement to proceed with expansion at Heathrow.
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