Simon Wilson is an award-winning senior writer covering politics, the climate crisis, transport, housing, urban design and social issues, with a focus on Auckland. He joined the Herald in 2018.
Since the draft new Setting of Speed Limits Rule was released in June, much has been said about its road safety implications. But Brown says it will improve economic productivity by allowing people to “get to where they want to go more quickly”.
What does the evidence say?
The minister doesn’t really deny safety will suffer. His focus instead is on how silly it is to have to drive slowly. In a newsletter to National Party supporters in July, he said the issue was lower speed limits “were forcing motorists to drive at a snail’s pace”.
And last week he told TVNZ the only way to eliminate deaths and serious injuries (DSIs) would be to “reduce the speed limits to zero”.
Our DSI rate is not normal or inevitable. As the International Transport Forum reports, it’s twice as bad as Australia’s and three to four times worse than in other comparable countries such as Britain, Ireland and Norway.
After two years, the independent research group Abley found deaths on those roads had dropped 30%.
This wasn’t a Covid phenomenon. During the same period on Auckland’s other roads, deaths rose by 9%. The overall fall in serious crash numbers was 22.3%.
But we’re being asked to accept that more deaths and injuries are the price we must pay to help businesses and grow the economy.
Is that true?
The idea that higher speed limits will boost productivity rests on the answers to two questions.
First, are travel times the best way to measure the economic efficiency of transport? Second, will higher speed limits make congested traffic move faster?
The first is only partly true. If it takes less time to get from A to B, you’ll be able to get more done. But economic efficiency involves more than that.
In a 2017 study, the NZ Transport Agency Waka Kotahi (NZTA) sent a driver on three routes of more than 200km each. One of the routes was Auckland-Tauranga and each was done with more than 100 trips, some with a 100km/h speed limit, some with 90km/h and some with 80m/h.
The fuel cost of the fastest trip was 14-15% higher than the lowest. The average time saving, for a trip of nearly three hours, was 10 minutes.
But travel cost and time is not the biggest economic issue. NZTA also reports annually on the “social costs” of road crashes. In 2023 those costs were put at nearly $12 billion - about 3% of GDP.
That’s crash victims in the public health system, crashes taking first responders away from other vital work, a massive drain on ACC payments, a myriad other costs associated with the trauma and heartache of lives destroyed.
Compare this data to the often-quoted research by NZIER for the Employers and Manufacturers Association in 2019. It found congestion on Auckland roads – which is the bulk of congestion nationally – was costing about $1 billion a year.
We can crunch these numbers. If crashes cost the country $12 billion a year and that can be lowered by 22.3%, it’s possible $2.7 billion could be saved. Congestion isn’t costing the economy that much.
The reality will be more complex, but this data suggests the economic argument for higher speed limits fails.
Transport Minister Simeon Brown is expected to announce this week that his rule to raise speed limits has been approved by Cabinet. Cartoon / Rod Emmerson
Which begs the second question: will higher speed limits reduce congestion anyway?
NZTA also tested city trips, including a 12km commute from Lynfield to Mt Wellington. The fuel saving was negligible and the average time saving in the morning peak was 2:13 minutes. How important are two minutes in your commute?
Even these findings are likely to overestimate the time savings, because lower speed limits help traffic best when they apply to everyone.
This is because for ideal efficiency, traffic should flow smoothly. The counter-intuitive impact of higher speed limits is that they can make traffic flow worse.
The Global Road Safety Facility, part of the World Bank, reported in 2022 that on busy urban roads the best speed for getting everyone from A to B is 30km/h or less. Stop-start driving, which causes bunching, is reduced. Cars travel closely together and it’s not hard for others to join the flow.
“Congestion means that the traffic is not able to reach the speed limit,” it said, “and thus higher speed limits will not solve the problem of excessive traffic for the road space available.”
It’s the exact opposite of what Brown says will happen with faster speed limits.
He’s right that congestion undermines productivity. But congestion is not caused by low speed limits. It’s caused by too much traffic.
If he was serious about this, the minister would move as fast as possible to reduce the number of vehicles on the road.
There are ways to do it. Overseas experience points to congestion charging, or tolls at peak times, provided public transport is good enough.
Auckland Mayor Wayne Brown wants improvements to rail freight, to take trucks off the roads. He’s right about that, and about desire for more dynamic lanes, less parking on arterials, smart traffic lights and other tech-related ways to manage traffic flow.
Auckland Mayor Wayne Brown and MP Simeon Brown.
Photo / NZME
How about a citywide campaign to reduce school traffic, with more cycleways, walking buses and other community initiatives?
Funding for new rapid transit services in the north, south, east and west could be prioritised. Low-cost technological alternatives – yes, including gondolas – should be trialled.
All of these things would be extremely cost effective and would not involve people dying.
But the Government has delayed congestion charging, new transit is also on a slow track and budgets for rail, cycling and many public transport services have been slashed. Instead, Minister Brown is stoking a culture war about cycleways and the meanies who make you drive “at a snail’s pace”. And the Prime Minister supports him in this.
Under the new rule, roading authorities wanting to lower speed limits in the future must obtain a strong cost-benefit analysis (CBA), which they’ve been doing anyway. But adding insult to very real injuries, Brown did not have to provide a CBA to justify his own rule.
The rule reaches a nadir in the way it applies to schools: a “variable” 30km/h speed limit will be imposed at the start and end of the school day, on a 300m stretch of road outside the school gates.
But Healthy Auckland Together, a coalition of 25 medical and public sector groups, reports that 85% of DSIs outside schools happen when variable speed limits are not operating.
This is because schools are busy places at many other times and most children live further than 150m away.
In 2022, AT commissioned the Flow consultancy to model several options for speeds around schools.
One was for a permanent 30km/h limit within a kilometre of the school gates (and variable on arterial roads within 400m). Over 10 years, Flow estimated that would prevent 468 deaths and serious injuries in Auckland and would have a BCR of 7.0.
Safety as well as economic value: what good public policy that would be.
The option closest to the minister’s new rule was for a variable limit within 400m of the gates. That would save 29 DSI over the next 10 years and have an estimated BCR of 0.2.
There’s no denying this issue divides us. A recent AT survey found 46% of respondents were in favour of the lower limits, with 38% against. Not conclusive, but not what the minister thinks public opinion is, either.
Two factors bear on this. One: The promise National made before the election was to “end Labour’s attempt to reduce all suburban streets to 30km/h and all state highways to 80km/h”.
Neither part of that statement is true: Labour’s plan never encompassed all suburban streets or all state highways. Yet the claim is still on National’s website.
Two: In its survey, AT discovered that when people were told the new limits had led to 30% fewer deaths, support for those limits rose to 61% and opposition dropped to 23%.
It’s possible. Evidence-based policy, with public support, a stronger economy and safer streets. And all you have to do is tell the truth.
