Costain, Interserve and Morgan Est chase Merseyside viaduct deal

Four rivals have geared up for a £70m deal to strengthen a crucial viaduct on Merseyside for the third time.

The line-up for the Bidston Moss project on the M53 is Costain, Bilfinger Berger, Interserve and Morgan Est.

It is expected that the Highways Agency (HA) will let the contract during early autumn this year. A start on site is expected around the Christmas 2008 period, although there is uncertainty over how long the work will take to complete.

An insider said: "That will depend on the solutions the winning contractor comes up with."

The viaduct is a 730m long box-girder structure carrying the M53 over the A554 roundabout and the Birkenhead to New Brighton railway.

The bridge is jointly owned by the HA, Wirral Metropolitan Borough Council and Mersey Tunnels.

During 1998/99, the viaduct had to be strengthened to meet new laws governing the introduction of 40t trucks onto the UK's roads.

During this project, further strengthening works were identified and heavy goods vehicles confined to the inside lane of the motorway as a precaution. But a further restriction early in 2005 resulted in only cars being able to use the viaduct.

Another second strengthening contract was then carried out to return hgvs to the viaduct, but only to the inside lane once more.