In brief

• AT implemented traffic calming measures despite knowing they could delay emergency response times.

• Emergency vehicles can save an average of almost 3 minutes by high-speed driving. 

• The  time saved by hurrying is then often lost by navigating traffic calming measures like speed bumps. 

• Analysts seem to have ignored  the  negatives of delayed emergency responses, which seem bigger than the traffic calming wins.

Are speed bumps costing lives?

Auckland Transport (AT) knew its installation of speed bumps, chicanes and other “traffic calming” measures was potentially costing lives by slowing down fire engines and ambulances, but it has pushed through the changes regardless.

A 37 page analysis in September 2023, by forecasting group BERL,  released to the Centrist by AT under the Official Information Act, is surprising for what it doesn’t contain.

It reveals BERL relied heavily on the alleged cost savings from preventing road deaths ($12.5 million per traffic life saved, so it says, but we are dubious), while not factoring in the costs of lives lost because emergency vehicles are getting to heart attacks, strokes and accidents too late.

“Time is critical, it can literally mean the difference between life and death. We put lights and sirens on the top of our vehicles for a reason and these things [speed humps] have the opposite effect. It’s absolutely region-wide,” NZ Firefighters union representative Martin Campbell told the Herald this week.

“While it may not seem like a huge delay, seconds count when it comes to both fires and medical responses… It is creating risk in the sense it’s taking us longer to get to incidents.”

The BERL report notes that emergency vehicles in city areas can save an average of 2.9 minutes by high-speed driving to emergencies, but this life-saving time window can be eaten by speed bumps, raised pedestrian crossings, chicanes, and traffic congestion caused by traffic lanes disappearing to be used as cycleways.

 The number of traffic deaths in urban areas is far lower than the total number of life and death emergency callouts in cities on any given day (about 100 people die of any cause in NZ every day, 22 of them aged under 60, while traffic deaths nationwide average around one a day).

 It therefore follows that any “cost benefit analysis” that only factors in road deaths and not other medical emergencies at a rate 22 times higher, probably isn’t worth the paper it is written on.

BERL places significant reliance on the long term impacts of traffic crashes:

“Economic costs are only one component of the impact of car accidents. The most devastating aspect of a car accident for a person may be these non-financial consequences. A person’s life may be severely restricted by a permanent impairment such as spinal cord damage, loss of mobility, blindness, or a severe brain injury which may leave them dependent on others for daily medical care.”

“The victim’s friends and family are also severely impacted by the effects of the injury. When an accident results in death, the emotional impact is far more severe, lasting for years and occasionally resulting in the dissolution of formerly stable family structures. The most tragic and, potentially, the most expensive component of such events would go unnoticed if the only consideration in making policy decisions was the economic effects of traffic accident.”

It is not much of a leap to observe those impacts can be just as devastating for a family watching a father or mother die in their arms at home because an ambulance couldn’t get there in time, and the macro numbers suggest there are 22 more of these types of risk situations  every day than there are road deaths.

AT’s response to the Herald has been one of denial, the newspaper reports:

“AT manager of transport safety, Teresa Burnett, dismissed the claim that raised crossings or speed bumps were a major cause of delayed emergency response times, instead citing traffic congestion as “causing the biggest issues”.”

Of course, calming devices can also cause congestion.