Hammersmith Bridge Plans Set to be Submitted

Published: 04/05/2023 By Allan Fuller

More details have been released about the proposals for a temporary structure at Hammersmith Bridge designed to accelerate its reopening to traffic. It is expected that a planning application for the designs are to be submitted shortly. 

Engineers Cowi and architects Foster and Partners recently held a series of public exhibitions at which their innovative plans for a double decker structure were detailed.

Cowi engineers at the events explained how they intended to build two massive steel trusses which would be placed north and south of the river then pushed through the bridge pedestals and the Tower Piers. These would then be joined at the centre to form a span over the existing road surface of the bridge.

The new structure would have two levels, the lower one for pedestrians and the upper one for motorised traffic. This would allow the resumption of bus services across the bridge although it is thought that it would only be possible to use single deckers with a limit of the number allowed at any time. It is not clear if cyclists would need to dismount on the walkways. The visualisation released by Foster Cowi do not show cyclists riding across the bridge and engineers said how they would cross has yet to be decided.

The existing bridge would then be dismantled piece by piece and lowered onto a barge to be taken to another location. There it would be checked for defects, refurbished with unwanted additions removed before being returned by barge. The existing stiffening girders on the bridge are at the end of their useful life and must be replaced according to staff from Cowi.

 
Barges would b used to remove sections of the old bridge for restoration. Picture: Foster Cowi

The engineers said at the presentations that this solution was the best all round because to repair the bridge on site would require a total closure for a prolonged period that would deprive pedestrians and cyclists access. It was also the quickest way to get motor traffic running over the bridge.

Suggestions that the bridge could just be left open without any attempt to restore motorised traffic were dismissed by the engineers who said that the defects in the bridge were so serious that it would likely need to be closed at some point even for pedestrians and cyclists without extensive repairs.

A pedestrian crossing would be provided on the lower tier of the structure. Picture Foster Cowis>

Assuming that the plans, which are to be presented to both Hammersmith and Fulham and Richmond Council, move smoothly through the approval process, the engineers say the temporary bridge could open by 2026. The work to repair the old bridge would then continue for a further two years for a possible reopening in 2028.

Single decker buses would be able to use the temporary bridge. Picture: Foster Cowi

A major question mark remains over costs and who will pay for the repair. Although Hammersmith and Fulham Council have heralded the proposal as cost effective compared to other options, inflationary pressures likely mean initial estimates of £160 million are to be exceeded. 

A toll has been suggested as one means of covering some of the costs and sources close to the project have intimated that they believe a change of government would significantly increase the chance of funding being available to complete the scheme.

The bridge closed to all motor traffic in April 2019 after serious defects were found in its structure. Since July 2021 it has been open to pedestrians and cyclists.