Councillor Rob Humby, Executive Member for Environment and Transport at Hampshire County Council, said: “Around 60,000 vehicles use this major route in and out of Southampton every day. The harsh marine environment has accelerated the deterioration of these concrete bridges which hold the A35, and repairs are essential if weight restrictions and lane closures are to be avoided in the future.
Redbridge Causeway is made up of four concrete bridges, built between 1930 and 1966 and is a key route into Southampton. All four structures which make up the Causeway need repair, at an estimated cost of £25 million. The County Council is treating the Viaduct as the priority and has allocated £8.4 million for repairs.
Councillor Humby explained: “At around £25million for all four structures, the estimated repair bill would be a substantial chunk of our highways maintenance budget and would mean other schemes elsewhere in the county would be delayed. So we’ve asked the Government to help cover these costs – the route is of major importance not only to the local economy of the South but the wider economy. The impact on the local roads and the Port of Southampton would be severe if restrictions over the viaduct had to be put in place.”
The major refurbishment work needed to the viaduct involves extensive concrete repair works and the installation of a cathodic protection system in the concrete columns and other supports.
Earlier this year, the County Council completed work to replace 21 expansion joints and a longitudinal joint across the Viaduct to stop water leaking into the concrete supports underneath. Highways teams used the closure required to complete maintenance works which included resurfacing the A35 between the Viaduct and Rushington roundabout, clearing highways drains, cleaning road signs and cutting back weeds and grass on the verges.