Tauranga residents depend on their cars more and are less likely to take public transport than any other city in the country.
Coupled with the city's growth, that has seen the city's daily traffic increase by an average of 8.9 per cent in a year.
Tauranga has - by quite a margin - the highest private vehicle dependency in the country with around 97 per cent of journeys taken by private car, according to New Zealand Transport Agency (NZTA) highway manager for Tauranga, Niclas Johansson.
It also has the lowest public transport uptake, the lowest cycling uptake and the lowest walking uptake, he said.
According to NZTA monitoring, in the year to July 2016, daily traffic increased by an average of 8.29 per cent in Tauranga and 8.01 per cent in the wider Bay of Plenty. The figures cited by the Infometrics Quarterly Survey for June are higher, at 9.5 per cent for the year.
Increased inward migration and a big jump in private and commercial vehicle numbers were driving the increase, Mr Johansson said.
The global financial crisis caused traffic numbers to plateau, he said, with the current increase reflecting an evening out of growth that would otherwise have taken place. However, the Tauranga traffic growth figures were approximately double the national increase of 4.6 per cent to June (Infometrics), or 4.86 per cent to July (NZTA).
"We've seen unprecedented growth over the past year or for sure," said Mr Johansson. "It's really fired back up again. It's in the eight per cent mark now, and we haven't seen that before."
While there had been significant investment in new roading developments, increasing infrastructure alone was not the long-term answer, Mr Johansson said.
"We really have to do something different," he said. "Tauranga at the moment is a very poorly performing city statistically in terms of our transport behaviours.
"We have to do it differently. We can't just keep four lane-ing everything."
Data supplied by the Bay of Plenty Regional Council showed the Bay has the second lowest level of trips per capita by public transport of five surveyed regions, just above the Waikato.
Gary Allis, Western Bay of Plenty District Council deputy chief executive/group manager infrastructure services, said getting on to highways from side roads was taking longer and becoming more dangerous because of the increase in traffic on main routes.
A shift into cycling and walking was needed, not just for commuters, but people walking within their neighbourhoods and children going to school, he said.
Tauranga City Council manager transportation Martin Parkes said the region's planners were trying to get a better balance in the network. He noted the regional council was also currently leading the development of a Public Transport Blueprint, with a focus on the Western Bay area and in particular Tauranga city.
"We've certainly got plans to put the necessary infrastructure in place over the next few years to manage the growth we anticipate in traffic," he said. "But certain parts of the network are under more pressure than others."
As well as the State Highway North, that included the big growth areas in The Lakes, Papamoa and Pyes Pa.
"A lot of attention is on those areas, where we're busy building new infrastructure to cope with the growth and the increase in traffic volumes as well," he said.
"There are going to be continual problems for a little while longer until those projects are in place. We've certainly been working with our elected members to bring projects forward and looking at the timing of others over the last couple of years. I think we were all a little bit surprised by the speed of the growth."
On your bike
Iris Thomas, a former spokesperson for Cycling Action Network, who teaches cycle safety in schools, said it was the right of every child in New Zealand to be able to ride a bike.
"It's what we used to do and I hope we're heading back that way now," she said.
"But traffic is becoming an issue. The roads are definitely much busier. You have to pick your times if you want to cycle to and from work and you often don't have the luxury of that choice.
"The council is providing many off-road areas for people to bike, which is excellent. We teach the children where the off-roads are, so if they want to bike they can use them as much as possible."
According to Infometrics data, in the year to June 2016, Tauranga experienced:
• A permanent and long-term net migration gain of 1161 people, compared with a gain of 818 a year ago, and a 10-year average loss of 73.
• An increase in new cars registered of 9 per cent, compared to the NZ average of 3.7 per cent, with a total of 7158 cars registered, compared with the 10-year average of 4674.
• A big gain in commercial vehicle registrations - up 31 per cent - and again higher than the NZ average increase of 6.2 per cent. A total of 1465 commercial vehicles were registered, much higher than the 10-year annual average of 755.