KEY POINTS:
Traffic heading between Auckland and the airport faces detours and possible delays tomorrow night, as long beams are installed for a new road bridge across the Southwestern Motorway.
The Transport Agency is advising motorists heading to or from the airport to allow an extra 30 minutes for their trips, in case of delays, and to listen to radio traffic reports for updates.
It intends closing a 2km stretch of the motorway between Mangere Bridge and Walmsley Rd from 9pm until 5am to install eight 22m beams, using a 300-tonne crane.
Traffic heading to the airport will be directed off the existing harbour bridge to Mahunga Drive before rejoining the motorway from Walmsley Rd.
For travel in the other direction, traffic will leave the motorway at the Coronation Rd offramp before heading through Mangere Bridge township to Rimu Rd's northbound onramp.
The beams will form part of the centre of a new four-span bridge to carry Rimu Rd over the motorway, which is being widened as part of the $230 million Manukau Harbour crossing duplication project between Walmsley Rd and Queenstown Rd in Hillsborough.
The existing Rimu Rd bridge has been closed to eastbound traffic, although a route will be kept open on a combination of the old and new structures for vehicles heading in the opposite direction from Mahunga Drive to Mangere Bridge.
