Traffic planners have a message for motorists during Apec - stay out of town. By Chris Daniels

There's one aspect of life in the city of sails that the 20 visiting world leaders won't get to see. That's the stalled traffic and impotent public transport system that Aucklanders love to hate.

But while the very important persons whisk past in their motorcades, for the rest of us the daily challenge of getting around town is about to get worse - much worse.

The busiest section of the country's road network, the Southern Motorway, will be closed for long periods, and traffic volumes need to drop by as much as a half to avoid total gridlock.

Wayne McDonald, one of the directors of consultants Traffic Design Group, has been working on the traffic management plan to help the city cope with Apec.

Main roads in the central business district, such as Albert St, will be totally closed on September 11,12 and 13.

Several other streets will be hit by temporary closures, as leaders travel to and from their hotels.

"If you take the CBD out of the system, then pressure is going to get put on the surrounding road network," said McDonald.

"The most important message is to encourage people not to come into that road network."

As the leaders travel to and from the airport on the motorway, traffic will be diverted onto secondary roads.

"The big concept is to use the North Western Motorway linked with St Lukes-Balmoral Road across to the normal route out to the airport, round the airport motorway, down through State Highway 20 and to the Takanini interchange."

People will be encouraged to "go around the city rather than into it or through it."

"For people who have to come into the city on Monday, they must understand the road closures are like a crucifix or cross in the city."

"The city will be in segments and you won't be able to hop in your car and drive from one quadrant to another - you just can't get across the city."

"The system will allow you to get in and out of where you might want to go but, having got in there, you can't drive from A to B."

People will have to think very carefully about the direction they approach the city from, said McDonald, so they end up in "the right quadrant".

The experience of the 1995 Commonwealth Heads of Government Meeting (Chogm)was that traffic levels could be expected to drop by 30 to 50 per cent on that day.

That was largely because thousands of motorists got the message and stayed out of town and off the motorways during the crucial days.

However a false sense of complacency, stemming from a perception that the road network coped well with Chogm, could be the traffic planners' biggest enemy.

"The position is that the street closures this time are more extensive and the motorway closure is more extensive than Chogm," said McDonald.

Recent motorway crashes on the Victoria Park viaduct and near the airport showed the serious effect that closing these sections of road had.

"Anybody gets stuck in a queue like that, once they're locked in they can't get out and can miss flights from the airport."

Traffic lighting phases will not have to be altered, said McDonald, as detectors in the road pick up changes in demand and automatically adjust the system to cope.

However some traffic lights around the perimeter of the central city will be changed to allow right turns where they are currently illegal.

A police helicopter, linked to the Auckland City Council's traffic light control room, would help keep track of problem areas.

Transit New Zealand hopes its new electronic motorway signs will be operating fully in time for the meeting.

These are linked to a network of new television cameras, placed on poles alongside the motorway and linked to a central control room.

Police Inspector Brent Holmes said the Apec traffic situation would be a "bad news, good news scenario."

"The bad news is that Auckland City could expect very heavy peak hour traffic all day, with periods where traffic will be at a complete standstill."

Despite the best laid plans of traffic engineers and transport planners, it is impossible to say how bad the problems will be.

The route from the city to Mt Eden, for example, will be subjected to unpredictable temporary road closures on Saturday as President Clinton and Chinese President Jiang Zemin travel to and from their summit meeting, planned for Government House.

Police will use "rolling blocks" for such an event. That means traffic lights will be locked on green along the motorcade route, and side roads will be closed for up to 20 minutes at a time.

The motorcades will have a police escort front and rear, but motorists ahead of or behind the motorcade will not have to get off the road.

This method - rather than completely closing the roads in question - is expected to be used when most of the leaders leave Auckland for the airport next Tuesday.

And although it might be a long drive to Auckland airport during Apec weekend, there should not be too many delays at the airport itself.

Apec delegates, media personnel and officials will all go through their own customs and border control gates when they arrive, and check in at special Apec counters when they leave.

Many people will, however be arriving in Auckland on normally scheduled commercial flights and go through customs as normal.