Flyunder report published

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Flyunder report published

Monday March 17, 2014

A report outlining plans to create a new ‘flyunder’ that could transform west London has today been published by Hammersmith & Fulham Council.

 View the report online

Open the online reader (opens new window)
Or download a PDF version: Hammersmith Flyunder feasibility study - H&F Council (7MB)

The ‘Hammersmith flyunder feasibility study’ sets out in detail how Hammersmith town centre might look if a road tunnel – dubbed the flyunder – were built beneath the current A4. It also explains and discusses the potential benefits change could bring to the area, including freeing up £1billion worth of former highway, which could unlock a net profit in excess of £500m to go towards financing the flyunder.

The report – published online at – includes feasibility, master-planning and geotechnical reports along with a strategic (economic) impact assessment. There are also several artists’ impressions of how the area might look if the flyunder were to go ahead.

Before and after images of the area around Hammersmith Apollo, The Ark, the Novotel Hotel, King Street and St Paul’s Church all show the six-lane-wide A4 removed and instead replaced with new homes, offices and green space.

Recently the Mayor of London, Boris Johnson, called the flyunder a ‘brilliant’ scheme after he met the Hammersmith & Fulham Council team behind the project. 

Speaking on LBC Radio on March 3, he said: “A presentation came in from H&F. They’ve been working for months on this idea of creating a new town centre in H&F. We’ve been listening to this for months and months thinking come off it this is never going to work and actually it is brilliant. It adds up. It’s a most fantastic scheme. We’re going to ‘tunnelise’ the flyover. What was interesting was even the hardened TfL engineers looked at all this – they’ve been very sceptical – and they thought it was a great scheme.”

The three tunnels in the council’s study vary in length from one mile to 2.5 miles, and it is likely they would cost £218million – £1.7billion to build. The shortest option would involve digging a ‘cut and cover’ tunnel 15 metres beneath the surface between just opposite Furnivall Gardens in the west and Hammersmith & West London College in the east.

Cllr Nicholas Botterill, H&F Council Leader, said: "This elevated concrete monster has divided Hammersmith town centre for decades – magnifying traffic noise and polluting our air in the process.  This project would reconnect our divided town centre with the river and make our once beautiful town centre an even more attractive place to visit or do business.

“This report is not an end point - it is a beginning. This is the council’s response to The Mayor of London’s Roads Taskforce and it is now mainly for TfL, who own and manage the A4, to decide how to take the project forward from here.”

The council is also looking at ways to weave the Mayor of London’s Better Junctions scheme to improve Hammersmith Gyratory and the road network in the area for cyclists into the next stage of the plans. Residents and businesses in the borough would also be heavily involved in any consultation on the Better Junctions project.

The £290 million project aims to make 33 roundabouts and gyratory systems across London less threatening to cyclists and pedestrians. Funding will be used to install schemes like direct segregated cycle tracks, two-way roads and traffic-free public spaces.

The programme is set to be designed over the next two years, with help from residents and local groups who will be consulted, while the scheme is expected to be approved and built in 2016/17.

To read the full flyunder report and for more information, to view the artists’ impressions or to leave a comment, visit:

For more information on the Better Junctions programme and the Mayor’s Road Task Force, click here (opens new window).

To read the key findings from the report, discussed at last month’s Hammersmith & Fulham Council transport select committee, visit this link.