Transport for London (TfL) has raised concerns over the impact Heathrow expansion will have on the capital’s transport network, warning over significant crowding.
In surface access analysis compiled this month, London’s transport body said Heathrow expansion is expected to result in an extra 170,000 daily passenger and staff trips compared to today.
The airport has pledged that there will be no new airport traffic on the roads compared to today, while the government has said Heathrow will need to set specific mode share targets to get more than half of airport users onto public transport.
But TfL has raised concerns over the feasibility of this – and what it will mean for London’s public transport.
In order to achieve no rise in highway trips, TfL says around 65-70 per cent of trips would need to be on public transport. That would work out as a 210 per cent increase on journeys at present.
TfL’s analysis of the surface access implications of Heathrow expansion draws upon what has been published by the airport, the Department for Transport (DfT), the Airports Commission and the Civil Aviation Authority.
It looked at the schemes currently committed as well as those assumed, though not committed or funded by the national policy statement, and said a three-runway Heathrow would likely generate 90,000 extra vehicle trips along with another 100,000 extra public transport trips each day.
Significant levels of crowding
This would have a knock-on effect on travel for non-airport users. In the morning peak for travel, there would be a three to five per cent rise in average highway journey times across west London as far in as Westminster, and for rail users, this will mean “significant levels of crowding” on the Elizabeth Line, Piccadilly Line and Windsor lines.
Airport-related traffic makes up as much as nine per cent and 16 per cent of all traffic in Hounslow and Hillingdon respectively, with TfL forecasting this to rise following expansion.
Its analysis also found that new public transport infrastructure by itself is not sufficient to secure no rise in highway trips. “To achieve this additionally requires the airport to introduce a significant road user access charge or local congestion charging scheme,” TfL says.
Raising parking charges alone, even to over £100, has little effect according to TfL analysis, as many of those choosing to park at Heathrow have “a high willingness to pay”, with those who do shift often opting for taxis.
Rise in jobs leading to rising transport pressures
The transport body has also flagged the omission of the impact of new jobs. Part of the economic case underpinning the decision for Heathrow expansion points to the substantial number of jobs that would be created, many in London. TfL says this would lead to “further pressures” on the transport network, but neither the Airports Commission nor the NPS have attempted to quantify this.
London mayor Sadiq Khan is a vocal opponent of Heathrow expansion, and in a letter to transport secretary Chris Grayling last month, he warned there was “a real risk” that “the taxpayer is forced into underwriting, if not subsidising the whole project”.
A Heathrow spokesperson said:
Our proposal to expand Heathrow will be entirely privately funded with no public funds required to deliver the airport infrastructure. Our plans to significantly improve rail, bus and coach connections will enable tens of millions of additional journeys by passengers and colleagues to be by public transport when travelling to the airport.
"We are also consulting on whether an emissions-based charge could be another way to reduce road journeys and support our sustainable transport plans," they added.
A spokesperson for the DfT said:
Heathrow has made a pledge that there will be no increase in airport-related traffic on the roads.
Our expectations on costs and surface access – including targets around public transport use – are clearly set out in the revised draft airports national policy statement. Applications for development consent will need to set out how they would meet these requirements.
It is understood that as part of the statutory planning process, Heathrow would be required to undertake a detailed transport assessment to scrutinise the impact of expansion plans.