'Flyunder' Unlikely To Mean Tunnel For Chiswick

Hammersmith project more likely to be ' cut and cover' option

A new flyunder for Hammersmith is unlikely to involve any tunnelling around Chiswick, according to the newly published feasibility study on the project.

One of the options explored had been a long bored tunnel linking Chiswick to Earls Court - however it is thought that a 'cut and cover' option starting at Furnivall Gardens in Hammersmith now looks like the most likely option. You can read the report, which was published on March 17th at www.lbhf.gov.uk/flyunder

view from Furnivall Gardens - artists impression

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. Even if the decision is taken to proceed with this less ambitious option it could take over a decade for the project to be completed.

Hounslow Council has said that while it was tempting to push for a tunnel to be taken even further west to replace the M4 elevated section through Brentford, it appeared that a large proportion of the traffic using the roads was local.

"Without a series of complicated ramps and portals providing access to a new undergroud highway-structures that would result in loss of property - some of it listed or of conservation value, and land area and act to simply displace severance-this traffic is likely to be rediverted onto the existing network (or the proposed replacement streets). The benefits of such a scheme may be insufficient to warrent the huge cost involved", Cllr Steve Curran commented outlining LBH's position in a letter to Hammersmith and Fulham Council.

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, according to the report.

The report 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 showing the areas around the Hammersmith Apollo, the Novotel, King Street and St Paul's Church after the current six lane width A4 is removed and replaced with homes, offices and green space.

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.”

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

March 19, 2014