Transport bosses hope for best

Soon after the motorway closed yesterday evening signs were good on Auckland roads. Photo / Herald on Sunday

Threatened with unprecedented congestion, Aucklanders stayed off the roads last night as authorities shut the busiest stretch of motorway in the country.

State Highway 1, southbound from Gillies Ave to Greenlane, was shut from 5pm, and traffic was diverted on to residential roads.

Just after the closure, southbound traffic was down 50 per cent on a usual Saturday.

"I'm really pleased with that. It's a good start - only 36 hours to go," said New Zealand Transport Agency traffic management centre manager Mark Walker.

But the agency fears the worst is yet to come, as traffic peaks at about noon today.

In the hour after the 5pm closure traffic was heavy on only a few of the diversion routes. Great North Rd near Pt Chevalier backed up.

"We're starting to see some queuing in some of the diversion routes," Walker said. "We're starting to manage traffic signals to prioritise the movements that will work best.

Although traffic was initially light, Walker warned motorists not to drive unless necessary. "If all these people decide to travel in the day, we're not going to be able to cope with the demand on the diversion routes.

"What we need for the public is to only consider essential travel over that period."

Agency spokeswoman Sharon Hunter said extra carriages would be hooked on to suburban trains, adding 10,000 extra seats to bring seating capacity to 25,000.

She did not expect delays to trains but warned travellers that buses would be affected.

"We don't know what the delay levels will be like," she said. "Particularly if they're going to the airport, if they're using the Airbus Express, make sure they allow for plenty of time."

Hunter said the fact there were free trains did not make them a ticket to ride round the city, and she urged people to use the trains only if necessary, and if not, stay at home.

Taxi driver Ajmal Malik said he and other taxi drivers would take a revenue hit from the jams.

"I think it will reduce our work by about 50 per cent," he said. "It will be because most of the people won't be coming into the city. Already Land Transport will be telling people to stay home."

He said in a traffic jam, customers were charged by the wait time as well as distance, making the trip expensive.

How to get from the Harbour Bridge to State Highway 20

* After the bridge, continue through to the Northwestern Motorway (SH16).

* Take the St Lukes exit and then turn left on to St Lukes Rd.

* Continue on St Lukes Rd for 2.4km and then turn right on to Sandringham Rd.

* Continue on Sandringham Rd for 2.5km and turn left on to SH20.

How to avoid the Harbour Bridge heading south from Northland

* Take the Upper Harbour Highway exit heading south past Albany.

* Turn right through the interchange to continue through on Upper Harbour Highway. Continue on Upper Harbour Highway to Hobsonville Rd.

* Turn left onto the Northwestern Motorway (SH16).