A report by the New Economics Foundation (NEF) think tank claims that environmental statements (ES) for regional airport expansions made by firms including Wood, WSP and RPS do not accurately present their true impact on carbon emissions. It calls for all active planning applications to be ‘called in’ by the secretary of state and recommends that the Department for Transport should produce "a more robust and precautionary evidence base".

However, the report has been branded as "misleading and factually incorrect" by Southampton Airport and refuted by WSP, which is assisting the airport with plans to extend its runway.

A spokesperson for consultancy WSP told Environment Analyst: "We are confident in the approach we have taken to calculate carbon emissions as part of the environmental statement for the proposed expansion."

Gatwick, Heathrow and Luton airports, the report notes intend to apply for expansion as ​nationally significant infrastructure (NSI) projects. In December, the Supreme Court overruled a successful appeal against a third runway at Heathrow, clearing the way for a new application (EA 18-Dec-20). Smaller, non-NSI expansions at Bristol, Leeds Bradford, Southampton and Stansted, are going through planning processes with local authorities. 

The report ​‘re-models’ the carbon estimates attached to planning applications. It presents what it claims is a more credible analysis of the environmental and monetary impact of each scheme. It claims that ESs "typically simplify the calculation of emissions". 

Specifically the report states: "This analysis highlights that scheme proponents (and the consultants working on their behalf) have failed to take a precautionary approach to their scheme assessment. Appraisals have failed to take a comprehensive and robust approach to sensitivity analysis of uncertain model parameters and have presented an overly-optimistic vision of the future climate impact of the proposed expansion schemes. 

It continues: "Consultants working on behalf of expansion scheme proponents typically simplify the calculation of emissions by modelling in detail only a selection of specific years, or ‘time slices’, rather than every year in the assessment period. Modellers then make simple assumptions about what happens over the full assessment period on the basis of the modelled years."  

Applications to expand Bristol, Leeds Bradford, Southampton and Stansted airports, says the report, ignore up to £13.4bn worth of potential damage to the climate collectively.

Steve Szalay, operations director at Southampton Airport, refuted the NEF report as "misleading and factually incorrect". He commented: "We have delivered a worst case scenario in the environmental impact assessment (EIA) presented which would see just a 164m extension to our existing runway."

"This conservative approach doesn’t rely on fuels or technologies that are under development and makes full provision for all in-bound and outbound flights. We are wholly committed to working with the wider aviation industry to tackle climate change through new technologies and the introduction of new, more sustainable fuel."

The report notes that the government’s sixth carbon budget for 2033-37 is expected to include international aviation emissions. It adds: "The government will need to demonstrate how proposed expansions can be reconciled with the climate change committee’s recommendation of a no-net-expansion policy on airports."

The report claims:

  • All four non-NSI schemes rely on optimistic estimates of long-term fuel-efficiency gains
  • Three ignore the fact that aerosols, water vapour and nitrogen oxide emissions have the potential to double or triple climate impact
  • Three out of the four assessments do not present the climate impact of inbound flights
  • Only one includes monetised impacts. The others have failed to test the impact of higher future carbon prices and increased taxes

Logo - New economics foundation

The London-based New Economics Foundation says it "works with people igniting change from below and combines this with rigorous research to fight for change at the top," with the goal to build a new economy within environmental limits.