Rain could postpone bridge repair work

Mangere Bridge is expected to close again to northbound traffic at midnight tonight for heavy repairs, and motorists heading to the airport between then and Sunday morning are warned to expect delays.

Transit NZ says a repeat of traffic jams which choked many Manukau City roads during a closure five weeks ago was averted last weekend, after motorists heeded pleas to keep well clear of the bridge and neighbouring suburbs.

Although southbound traffic flowed freely over the bridge then, regional operations manager Joseph Flanagan said delays could be caused this weekend by a need to divert vehicles across the Southwestern Motorway to its northbound lanes.

Despite a forecast of rain from about 6pm tomorrow, Mr Flanagan hopes work on the bridge surface to replace hefty expanding joints will be complete by then, leaving contractors to continue through the night on welding operations beneath it.

There remains a possibility, however, that the work will be postponed if the rain threatens to arrive too early.

Mr Flanagan said only about half the usual volume of southbound traffic crossed the bridge last weekend, putting less stress on detours used by vehicles returning from the airport.

He hoped drivers would not become complacent this weekend and assume traffic would flow as freely as last time, when workers welded two 10-tonne joints to the bridge's northbound structure.

All three replacement joints required on that side of the bridge are now in place, but motorists will have to put up with closures of the duplicate southbound structure for similar repairs this weekend and next.

Last weekend's work went faster than expected, allowing the bridge to reopen about 8.30am on Sunday, three hours ahead of schedule.

Mr Flanagan said the work this weekend would be more complicated, as the new joints needed to be lined up exactly with those already fitted, but he hoped the bridge would reopen by 11am on Sunday.

Transit will put more effort into persuading motorists leaving the airport to drive east down State Highway 20B and Wiri Station Rd to reach the Southern Motorway at Manukau.

It says this will offer a faster trip to central Auckland than a secondary detour, along Kirkbride Rd and around the Manukau Harbour from Favona Rd in Mangere.

A 1km section of another key Auckland arterial route, Hillsborough Rd, has meanwhile been reopened to eastbound traffic after several weeks of diversions while contractors rebuilt it.

Workers are now digging into a section of the road between Goodall St and Olsen Ave, where a lane in each direction is being kept open but where homeward commuters suffered serious delays last night.