Beyond the limits

Six weeks later, an AA Member survey found only 90 out of 855 Hamiltonians had anything positive or neutral to say about Hamilton City Council’s consultation on the speed limit changes. The torrent of dissatisfaction that we collated should worry any elected official.

And this issue is not going to go away. The pillars of the Government’s road safety strategy to 2020 are 'safer drivers, safer roads, safer vehicles and safer speeds'. 'Safer speeds' means that a programme of changing speed limits is being considered for the whole country. 

The 40km/h speed limit changes in Hamilton, Palmerston North and Dunedin were carried out under legislation allowing ‘demonstration projects’. In fact, there are quite strict laws about setting speed limits in New Zealand. If a road controlling authority changes a speed limit away from the default values of 100km/h for open road and 50km/h for urban areas without following those legal processes, the posted speed limit is legally null and void.

Perhaps not surprisingly, speed limit policies provoke a lot of strong emotions. People hate getting speeding tickets, and stung motorists are often quick to accuse Police of revenue gathering. Safety advocates, on the other hand, accuse motorists of selfishly disregarding the safety of child pedestrians. In fact, neither extreme is true nor particularly helpful.

The point safety advocates make is that when there is a collision on the roads, the laws of physics mean speed largely determines the severity of the injuries. But travelling too fast for the conditions also increases the probability of a crash. A puddle just 3mm deep can lead to loss of control at speeds as low as 80km/h. And the faster you go, the less time you have to react. On the other hand, billions of kilometres are driven each year at an open road average speed of 96.6km/h without incident, and restricting speed unnecessarily hits productivity on free-flowing roads.

The trouble is, speed limits are more than just limits; they’re considered by many motorists to be road quality guides. They treat speed limits as targets, assuming the signs would not indicate the speeds they do, if those speeds were not safe to travel at. Rather than try and re-educate 3.2 million drivers, the Safer Speeds policy will attempt to bring speed limits into line with road geometry, optimal traffic flow and safety.

The model being looked at as part of this exercise is European. In that part of the world, many local roads – deemed ‘play streets’ and as likely to host a kids' soccer game as cars – have very low speed limits. Beyond them, collector and arterial roads, which typically have 60km/h limits, are meant to move traffic quickly and often have separate cycleways. Outside cities there are two classes: rural roads, usually with a speed limit of around 90km/h; and motorways, which start at 110km/h to 130km/h and go up to unrestricted speeds on some autobahns. Of course, the speed limits match the design of the roads themselves. 

Our roads are different. Professor Sam Charlton of Waikato University Traffic and Road Safety Research Group provides an excellent illustration of several New Zealand roads which look identical, but which all have different speed limits. Given that people miss speed limit signs two times out of three, the conclusion is that people read the road for clues for appropriate speeds. A trial in Auckland by Professor Charlton lowered speeds by changing the road clues rather than the limit. Unfortunately, this approach would be too expensive to use everywhere in New Zealand, so intermediate solutions using road markings that have to be re-painted every two years are more likely to be adopted.

But, making changes that suit everyone will be difficult. The AA has carried out a number of surveys on this issue and found that, two to one, Members do not support 40km/h urban limits and would like 110km/h motorways. We’ve also discovered Members like the idea of a 40km/h urban limit outside their own house, but not outside anyone else’s. AA Members perspectives change depending on whether they are trying to get to school to pick up their kids, riding with their children on bicycles or driving past a bunch of road cyclists hard riding two-abreast on the highway and holding them up. 

Ultimately, changes without broad community support are not politically sustainable. But lessons were learned over the Hamilton experiment, so hopefully road controlling authorities will listen carefully to their customers and not make changes without adequate support.