The NZ Transport agency has installed the first five of 234 concrete bridge sections for the new northbound section of the Newmarket viaduct on Auckland's Southern Motorway (State Highway 1).
Each segment weighs between 70 and 90 tonnes and is being raised into place by the big blue lifting gantry that sits across the top of the viaduct.
Construction of the northbound lanes has started at St Marks Road at the southern end of the viaduct. The blue gantry will work its way northwards to Gillies Avenue, lifting the concrete segments as it goes. The job will be completed early next year.
Despite the technically challenging project, the NZTA and its partners (Leighton Contractors, Fulton Hogan, VSL, URS, BECA, Tonkin & Taylor and Boffa Miskell) are constructing a new viaduct and deconstructing (removing) the old one built 1965 in stages while the busiest section of the Auckland motorway network remains opens.
"We've been able to do that because of the good support we have had from drivers," says the NZTA's State Highways manager for Auckland and Northland, Tommy Parker. "Drivers are travelling through a live construction zone and sometimes there's little more than a metre separating our workers and motorway traffic.
"The reduced speed limit of 70kph is the key mechanism in allowing us to keep the motorway open at virtually full capacity throughout the replacement process. Driving conditions are more challenging with the motorway lanes temporarily narrowed across the viaduct. We urge all drivers to continue to observe the lower speed limit for their own safety, the safety of their passengers, and the safety of viaduct workers."
The Newmarket Connection: Viaduct Replacement Project replaces the existing viaduct, which was constructed in 1965. The new northbound lanes are being constructed in the gap left after the removal of the viaduct's old southbound lanes. When complete, the existing northbound lanes of the viaduct will be removed.
The new viaduct is seismically stronger and has more capacity for traffic. It marks the southern end of a series of improvements to the Central Motorway Junction (CMJ). Together with the Victoria Park Tunnel under construction at the north end of the CMJ, it will help improve travel times and safety. The project includes urban design improvements under the viaduct to benefit the business and residential communities of Newmarket.
For more information on the Newmarket Connection: Viaduct Replacement Project, visit www.nzta.govt.nz/newmarketconnection.