Surprise! Auckland's traffic picks up speed

Auckland drivers on a slow motorway grind towards the new Sylvia Park shopping mecca may be surprised to learn that congestion has eased marginally in the past few years.

Admittedly, there is not a lot to celebrate, given confirmation from a Transit NZ survey that Auckland is still more clogged than other sizeable New Zealand cities.

But an average speed of 39km/h on 300km of selected motorways and arterial roads in the morning traffic peak during a check last November was no slower than 12 months earlier, and higher than in all other previous surveys back to 2002.

The slowest crawl by a Transit survey vehicle was in March of 2003, when the weekly morning peak average dropped to 32km/h, a low blamed in part on atrocious weather.

Even by March last year it was just 35km/h, although Transit says significant seasonal variations make comparisons problematic between that month and November.

Auckland commuters still creeps to work painfully slower than morning averages recorded in November last year of 50km/h in Tauranga and of 52km/h in Wellington. But Transit network operations chief Roly Frost told the Weekend Herald that the agency was pleased congestion in Auckland appeared to have stabilised, despite considerable growth in traffic volumes of about 3 per cent a year.

"We have managed to improve efficiency," he said.

A comparative figure is unavailable for Christchurch, which has not done much better than Auckland in recent years in March morning peaks, but was not surveyed in November.

Auckland commuters still faced delays averaging 36 seconds a kilometre in the morning peak, compared with travel times at what is called a nominal travel speed of 64km/h, which is derived from a combination of speed limits on motorways and other roads.

That means people living 10km from where they work took six minutes longer to get there than in free-flowing conditions.

But that compared with just under a minute's delay for each kilometre in March of 2003, although travel times in November's morning peaks varied by 24 per cent, meaning trips could take a quarter longer than expected.

Transit says variability of travel times, while frustrating to drivers, can have a significant economic impact by hampering freight deliveries.

Auckland traffic is not much better off in afternoon traffic peaks, when an average speed of 40km/h was recorded in November, resulting in an average delay of 33.6 seconds for each kilometre travelled. But the region's motorists at least got some respite between peaks, when the delay was reduced to 6.6 seconds a kilometre as the average speed rose to 58km/h.

That was faster than in Tauranga, when both the morning and afternoon peak speeds were 50km/h, but the average was just 55km/h between peaks and 54km/h at the weekend against a nominal travel speed of 78km/h.

Transit acknowledges in a paper to its board that this means congestion in Tauranga has become "an all-day occurrence", and that the overall weekday average speed has declined to 51km/h from 57km/h in 2003. Mr Frost said Transit was keeping a close eye on Tauranga.