A few weeks ago, I wrote about some misguided commentary on road safety that implied that “distracted walking” was a serious problem. It isn’t by any reasonable measure, but many of our other transport practices are unsafe.
On average, around 300 people die as a result of road crashes. Around 15 percent of the deaths are pedestrians and cyclists, who would have been perfectly fine if a motor vehicle hadn’t run into them. Another 1500 people suffer serious injuries in road crashes. And while road deaths are on a downward trend, the number of serious injuries has hardly changed over the last decade.
Some of these people chose to take on the risk of death or serious injury when they got behind the wheel. But others had the decision made for them – by someone else’s recklessness or by bad street design. So it’s worth asking: are there things that we could do to reduce these risks?
A few years back, Citylab published an excellent interview with Swedish traffic safety expert Matts-Åke Belin, who helped design Sweden’s “Vision Zero” approach to road safety:
Since approved by the Swedish parliament in October 1997, Vision Zero has permeated the nation’s approach to transportation, dictating that the government manage the nation’s streets and roads with the ultimate goal of preventing fatalities and serious injuries.
It’s a radical vision that has made Sweden an international leader in the area of road safety. When Vision Zero first launched, Sweden recorded seven traffic fatalities per 100,000 people; today, despite a significant increase in traffic volume, that number is fewer than three. To compare, the number of road fatalities in the United States is 11.6 per 100,000.
As of 2014, New Zealand had 6.5 road deaths per 100,000 people. So it’s roughly where Sweden was 20 years ago.
In the interview, Belin made one comment that particularly stuck with me:
In Vision Zero, the accident is not the major problem. The problem is that people get killed or seriously injured. And the reason that people get serious injuries is mainly because people have a certain threshold where we can tolerate external violence, kinetic energy. And we know quite well now how much violence we can tolerate.
One of the major things with Vision Zero now is to put that more explicitly on the table. It’s like if we’re talking about the environment, and you know you have a certain threshold when it comes to poison, or whatever. You can tolerate up to a certain level. So it’s not just to stop the traffic. You can actually allow traffic. But if you have places in your system where you have unprotected road users and protected road users, according to Vision Zero you can’t allow a higher speed than 30 kilometers per hour [18.6 mph].
Because if you have, as we did in Sweden before, 50 kph [31 mph] as the default speed in an urban area — if you get hit by a car at 50 the risk for a fatal accident is more than 80 percent. But it is less than 10 percent when you have 30 kilometers per hour.
Clearly we have seen it is not enough to, for example, change the speed limit. You maybe have to put in speed bumps. You have to think through all the conflict spots that you have in your traffic system. And do things about it.
Speed, in short, is a fundamental determinant of whether people die in crashes or walk away. We can’t eliminate accidents entirely, because humans aren’t perfect (and neither are machines), but we can reduce the consequences of making a mistake.
The role of speed was highlighted by the Cycling Safety Panel convened by the government in the wake of a 2013 coroner’s inquest into cycle fatalities. They published the following graph to illustrate: The risk of death or serious injury for pedestrians hit by cars is four times higher at 50km/hr than at 30km/hr:
However, as Belin observes, speed isn’t just a function of posted sign limits – it’s also about the design of roads. Road geometry must encourage people to keep to safe speed limits.
Unfortunately, it’s likely that road design standards encourage speeding. That’s illustrated in this chart from a Ministry of Transport review of speeding-related crashes, which found that the average free-flow speed on urban roads was higher than the posted speed limit. 15% of cars travel more than 5km/hr over the speed limit.
In short, our default urban speed limits are too high for pedestrians and cyclists to be safe in the event that they’re hit by a car… and road designs encourage people to drive even faster.
This has a number of direct and indirect consequences. The direct consequence is that people die, needlessly. The indirect consequence is that many people choose not to walk or cycle at all – a rational response to a dangerous road environment. That in turn leads to health problems and premature deaths down the track as a result of physical inactivity.
So what could be done?
The good news is that safety is a major priority for the NZ Transport Agency. They recognise that speed is a big part of that, but I’m not aware of any concerted effort to reduce urban speed limits, or make it easier for local road controlling authorities to do so.
The bad news is that there isn’t a major public conversation about safe speeds. But it’s starting to come up on the political radar. For example, the Green Party made lowering speed limits near schools a key part of the “safe to school” policy they released in March:
Safety is the number one concern that stops parents from sending their child to school on foot or by bike.
When parents wave goodbye to their child in the morning they should know they’re going to be safe when riding their bike or walking with their friends to school. […]
- Reduce the speed limit outside urban schools to a much safer 30 km/h
- Reduce the speed limit outside rural schools to 80 km/h, with the option of a 30km/h limit during drop-off or pick-up times
- Allocate $50m a year for four years to build modern, convenient walking and cycling infrastructure around schools: separating kids and other users from road traffic, giving a safe choice for families
- Get half of kids walking or cycling to school by 2022: reducing congestion; improving health and learning; saving families time and money
The devil’s always in the details with proposals like this. For example, how far around schools would the 30km/hr zone apply? But if we were looking to trial lower speed limits in urban areas, it would be really sensible to start with the roads around schools. The benefits are likely to be higher, as kids are especially vulnerable when walking by the road.
What do you think we should do about urban speed limits?