Engineering work is due to begin this month on the Hammersmith Bridge to ensure the safety of the structure.
It comes after the Hammersmith & Fulham board approved Mott MacDonald’s alternative stabilization plan in August.
Despite work starting in the coming weeks, the council has yet to receive funding assurances from the Department for Transport (DfT).
When the plan was approved in August, the council put in place the necessary capital of £6m – with a view that the DfT and Transport for London (TfL) would later repay a third of the costs each.
However, Richmond MP Sarah Olney revealed that the DfT is still assessing the business case for stabilization work.
In a blog post, Olney adds, “I […] heard from Hammersmith & Fulham Council (LBHF) who confirmed that a business case has been submitted to the DfT for the bridge stabilization works.
“I understand that the business case will now go through the DfT approval processes which, when approved, will allow the release of DfT and TfL funds, in line with the Tripartite Cost Sharing Agreement of the last year.
“However, LBHF explained to me that, as they wish to waste no time in making the bridge permanently stable to transport pedestrians and cyclists, they proceeded with the capital expenditure approval for the stabilization plan in anticipation of the DfT releasing their one-third funding.
The Hammersmith Bridge reopened to pedestrians and cyclists last summer, around 10 months after it was closed over fears of a catastrophic collapse. It has been closed to motorized traffic for more than three years after cracks appeared in its cast iron structure.
The council settled on Motts’ design after commissioning WSP’s Head of Civil, Bridges and Soil Engineering, Steve Denton, to carry out a review of the proposal and compare it to Pell Frischmann’s original plan.
He concluded that Motts’ proposal was “technically superior”, could be implemented more quickly and was “more cost-effective” than the £30 million program proposed by Pell Frischmann.
The Motts solution requires the removal of the end panels to install a temporary frame on the deck. The deflection saddles will then be lifted from the pedestals using a system of oblong flat jacks to facilitate the replacement of the existing steel rollers with laminated elastomer bearings.
Talk to NCEDenton pointed out that Motts’ proposal benefited from being drafted after the bridge investigation was completed, adding that Pell Frischmann’s original proposal made sense at the time it was drafted.
As well as saving £24million and reducing the works program to 46 weeks, the new plan – which has also been favorably reviewed by Historic England – is expected to reduce the need for temporary closures. Engineers believe it will also avoid having to reroute gas lines across the bridge for stabilization work.
While the stabilization work is being carried out, council will develop plans for additional work to restore the bridge to its former glory. It has previously been estimated that the cost of a full restoration could be between £141m and £163m.
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