Costain has finished strengthening the M53 Bidston Moss Viaduct in the Wirral three months early.
The structure is now capable of carrying the full HA and 45T of HB traffic loading, allowing more than a decade of weight restrictions to be lifted.
With more straight forward refurbishment of the £90m project left, it is on course to be the first job of its kind to come in on time and within budget.
Refurbishment jobs like painting, drainage, lighting renewal, cathodic protection, joint replacement and other highway works will now get underway.
The integrated ECI team comprises the Highways Agency, Costain, designer Amey, steelwork specialist Cleveland Bridge UK, Denholm, which will handle access, blasting and painting and VVB for all power and electrical requirements.
Andrew Watson, Highways Agency NW Director said: “This is great news and a huge milestone for the project to achieve.
“The fact that it has been achieved three months early is evidence of how well the project is being delivered.
“Everyone involved in the project should take a great deal of credit in getting this 11-year-old problem on the network solved.”
The complex critical strengthening work relied innovative box girder design and over one million man hours and 100km of new weld in extreme confined space conditions to strengthen the 3.7km of steel box girder.
Off peak M53 and local road traffic management will continue to be utilised until the end of the contract to facilitate these refurbishment works.