Yesterday, Auckland Transport announced:

New and safe speed limits on more than 600 roads across Auckland will come into force from 30 June 2020 onwards.

In an email they also advised:

This tranche will be completed by November 2021.

It’s a huge relief that these changes bringing in safe speeds have not been cut in the emergency budget. The work Auckland Transport’s safety staff have done has been extensive and impressive.

In the end, though, it will be nearly four years between the Road Safety Business Improvement Review and the completion of just the first tranche of speed limit changes. In a separate post we’ll look at how AT could change the approach they take to get changes rolled out across the city.

In this post, however, I’m going to look at government’s role. The onus on government to ensure we have safe speeds has increased this year, with new guidelines from our peak roading organisation, and the signing of an international declaration about road safety.

It appears New Zealand must take faster action on safe speeds than the road controlling authorities can be expected to manage.

If approaching vehicles were travelling at 30 km/hr (or less), the fellow on the bike would indeed be able to make a safe decision to move. People in cars, too, benefit from safer speeds by being able to turn out of side roads safely.

Imagine if the government made decisions about our streets on the basis of keeping us safe and well, in the same way that our collective wellbeing was the priority during the Covid 19 pandemic.

If our speed limits matched the research (and the rhetoric), we’d see a big drop in people dying or getting hurt on our roads, but the outcomes would go far further. Neighbourhood streets would be quieter, communities more socially connected, and walking and cycling would be attractive. This would allow children to travel independently, adults to travel actively, and we’d find it easier to meet our health, environmental and climate goals.

New Zealand’s current speed limits

The Setting of Speed Limits Legislation was passed in 2017, nearly three years ago. In its summary of feedback, Waka Kotahi / NZTA explained a practice that is worrying:

The proposed Rule requires that [Road Controlling Authorities] must aim to achieve a mean operating speed less than 10% above the speed limit… Requiring a target mean operating speed of 10% above the speed limit is an achievable and reasonable measure of performance.

And yet: the road code says you can drive “at or below” the speed limit. The police say the speed limit is a limit, not a target. So – statistical definitions notwithstanding – no-one should ever aim to achieve a mean operating speed above the speed limit.

Furthermore, the posted speed limits are known to be unsafe:

A Transport Agency (NZTA) tool shows 87 percent of speed limits on New Zealand roads are higher than is safe.

In fact, the situation is even worse than that, because although this tool recommends speeds lower than what our roads have, the Vision Zero speeds we need are even lower. Sure enough, when Auckland Transport investigated this tool for its own purposes, it found:

the information is not appropriate or accurate enough for safe urban speeds through town centres.

In summary, this should NOT be the order:

Mean operating speeds
Posted speed limits
Speed limits recommended by Waka Kotahi’s tool
Safe speeds

Submissions from the public showed a strong push for reduced speeds in general, and changes to the default speed limits:

A large number of submitters called for a general reduction in speed limits and with it, a reduction in the default speed limits of 50 km/h for urban roads and 100 km/h for rural roads…

But Waka Kotahi chose to avoid default speed limit changes:

Wholesale change to the default speed limits would be a high impact change and is not considered necessary or desirable…

Waka Kotahi is now a Vision Zero organisation, which requires an overhaul of this position.

Public opinion continues to be in favour of lowering the speed limits:

In the meantime, we’ve had three years in which the government left the change up to individual road controlling authorities to sort out – piecemeal, slowly, with expensive area by area analysis, and painful engagement, consultation and signage requirements.

We can do better. Like the current pandemic, unsafe speeds are a national problem that needs to be resolved with alacrity by central government in a way that gives value-for-money and minimises the local effort required by authorities and advocates.

What should the speed limits be?

In February this year, Austroads adopted the following safe speed limits in its guidance:

  • 30 km/h – Where there is the possibility of a collision between a vulnerable road user and a passenger vehicle
  • 50 km/h – Where there is the possibility of a right angle collision between passenger vehicles
  • 70 km/h – Where there is the possibility of a head on collision between passenger vehicles
  • ≥100 km/h – Where there is no possible side or frontal impact between vehicles or impacts with vulnerable road users

Wikipedia says:

Austroads is the apex organisation of road transport and traffic agencies in Australia and New Zealand. It publishes guidelines, codes of practice and research reports that promote best practice for road management organisations in Australasia.

Emergency safe speeds planned in Nelson.

Austroads’ guide Integrating Safe System with Movement and Place for Vulnerable Road Users highlights the importance of considering reaction times:

A driver travelling in a car at 30 km/h can stop for a pedestrian or cyclist in around 15m. A driver travelling at the urban default speed limit of 50 km/h can stop in around 31 metres and will still be travelling at 50 km/h when the vehicle reaches the hypothetical pedestrian or cyclist in the vehicle’s path when it reaches the conflict point at a distance of 15m. This impact speed coincides with a low chance of a struck pedestrian or cyclist surviving

The difference between 30 km/hr and 50 km/hr really can be the difference between no crash at all, and death.

In February 2020, the same month Austroads published its new safer speeds guidance, the New Zealand government signed the Stockholm Declaration, which commits us to comprehensive road safety improvements, including on speeds:

Focus on speed management, including the strengthening of law enforcement to prevent speeding and mandate a maximum road travel speed of 30 km/h in areas where vulnerable road users and vehicles mix in a frequent and planned manner, except where strong evidence exists that higher speeds are safe, noting that efforts to reduce speed in general will have a beneficial impact on air quality and climate change as well as being vital to reduce road traffic deaths and injuries.

Note the use of the term maximum road travel speed. The mean operating speed will need to be lower than this.

Many of our roads already have intuitive speeds way lower than the posted speed limits, but the posted limits encourage drivers to drive too fast for the conditions. This is never more clear than when you’re reminded of the “normal” speed limit after road works – as on this short street.

There is no remaining doubt that these speeds must be brought in. So why aren’t they being introduced immediately?

One spanner in the works is the idea that you need to change the road design to make the new speed seem intuitive. The excuse seems chiefly to be based on trying to prevent drivers from getting ‘unfair’ speeding tickets; a consideration of far less importance than trying to prevent people from dying.

And the argument is false:

  1. It ignores the fact that many of our speed limits are higher than the intuitive speed for the road.
  2. The science shows that if even a small area of a city receives speed limit reductions – without any other changes such as enforcement – the average speed comes down a few km/hr, which is enough to reduce injuries and death.
  3. When enforcement is provided as well as lowering the speed limits, the average speed comes down much more.
  4. Lowering default speeds nationally, with enforcement, may have an even higher effect than the studies on small areas, because doing this at scale could change the overall driving culture.

Auckland Transport made this case itself:

Roadwork to a higher standard will take time. This is why Auckland Transport is reducing speed limits as an immediate, cost effective and efficient way to decrease the number and severity of crashes in the Auckland region.

And on whether the road design is all-important anyway, research by Glen Koorey found drivers base their decision on what speed to travel at from a combination of different factors. The road design is not as big a factor as posted speed limits, the level of enforcement, and

the general societal/cultural norms for respecting laws, perceived appropriateness of the speed limit

I contend that people’s perception of the appropriate speed limit shifted during Level 4. And the level of respect for the law, in order to collectively keep our population safe, was impressive. But – so far – the government has squandered the opportunity.

The speed is surely incorrect for a street of this type? The same is actually true for almost every street in Auckland.

During Covid

During Levels 3 and 4, many people ventured out onto their local streets on foot or bike and became better acquainted with their community. Children and beginners gained confidence riding their bikes on the streets. The danger that cars present when travelling at 50 km/hr suddenly become apparent to many people.

The public’s heightened awareness of safety, traffic noise and air pollution dissolved the usual resistance to suggestions involving change.

That was the moment to usher in a better driving culture, and it would have been a natural addition to the public health approach New Zealand was collectively pursuing. Had we been given default safe speed limits at the beginning of Level 4 – with police enforcement – a new driving culture would have had a chance to develop. As economic activity resumed, those lowered speed limits would have allowed people to continue walking and cycling, achieving the modeshift that change-averse officials claim is so hard to achieve.

Tasman District Council responded to a Councillor’s concerns, implementing emergency speed limits in Richmond.

New Zealand is strong enough to catch up on road safety

Last year, New Zealand’s speed conversation slipped into ethically murky places, with arguments that amounted to saying it was ok to sacrifice our loved ones in support of “The Economy”.

Today, things are different. We’ve seen different countries’ and leaders’ responses to the pandemic, and most of us have been disgusted at those trying to prioritise “The Economy” over people’s lives. Perhaps it is clearer now that our people are actually the foundation of “The Economy” – not something to be traded off against it.

Throughout the emergency, public health officials have had the ear of the prime minister. For the virus itself, she was receiving quality advice, and acting on it.

Were the public health officials giving her quality advice about the public health value of safer speeds and the need to act during the pandemic? If they weren’t, do they need some workshops about transport implications on public health? And are they aware of the Stockholm Declaration?

It is clear the onus is now on government to ensure our speeds are changed, comprehensively. The question now is, how are they going to do this quickly, using evidence, and democratically?

The public would probably have been most receptive during lockdown – hence the feeling that the government lost an opportunity. On the other hand, we can see the scale of our success in tackling the spread of the virus (touch wood!), so we can see the benefits of taking pre-emptive action to save lives. Memories are still fresh of those sunny autumn days when our streets felt safe enough to bike with children and to cross at will – and when we all saw with fresh eyes how intrusive a vehicle is when it barrels through a community at 50km/hr.

Now is the time to change the default speed limits so they are safe.

We know our Prime Minister can lead in tough times, and overcome barriers to helping keep each other alive and well. We don’t need to look any further for leadership strong enough to make the streets where we live the kind and resilient places they should be.

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  1. Good to see some of the limits finally being reduced as a result of that consultation, however besides the City Centre and selected rural areas there is little happening in much of the urban area. Its unfortunate that they didn’t do the entire region at once, as many areas will now have to wait additional years for safe speeds…

  2. Part of the problem is the speed limit and part is whether people actually obey it. In my village situation, all the data recording speeds show that somewhere between 40-50% of the vehicles exceed the 50km limit with a few going significantly faster. There is effectively no enforcement. It would be great if the limit was 30km. But in many urban streets where we want people to cycle and walk we also need traffic calming measures to ensure the speed limits are obeyed.

  3. We don’t have to obey any of these limits. If you get stopped just tell the Police you are protesting the murder of someone you don’t know in a country on the other side of the world that has a long history of murdering people.

  4. Might as well go back to using horses and carts since we’re eschewing progress*

    *yes there are some places that need different and/or lower limits but not as extensively as this.

    1. Our speed limits haven’t increased in 60 years, I’m pretty sure we eschewed going faster on roads as an indicator of progress a long time ago.

      My suburban street that is used as a rat run isn’t on the list for a lower speed limit, so I’d argue that they don’t go far enough.

      1. 1974 actually. The urban speed limits increased. The open road limit increased to 100km/h in 1979 or 1980. Then a few years ago (2017) the top speed of 110km/h was introduced.
        In the meantime new speed limits like 60 or 80 have been introduced in urban areas for roads that would have previously been limited to 50.

        1. The increase in 1974 was from 48kmh (30mph) to 50kmh as a result of switching to the metric system, so technically you are right but it’s a matter of rounding.

          Prior to 1973 the open road speed limit was 97kmh (60mph), this was reduced to 80kmh due to the oil shocks, it returned to 100kmh in 1985.

          You could count on one hand the number of roads around the country that had an increase from 50kmh to 80kmh and they were likely due to significant improvements to the road. Those with 60kmh limits are split reasonably evenly between having previously 50kmh or 70kmh.

          Overall there has been a general reduction in speed limits in the last 20 years with many 100kmh roads becoming 70, 80 or 90.

        2. Perhaps notably, when the open road speed limit was reduced in 1973 there was a big drop in fatalities and injuries on rural roads. Correspondingly, when the limit went back up in 1985 it was followed by a jump in fatalities/injuries. In both situations, nothing else was done to change the roads, just a change in speed limits. I looked at what other external factors were happening around the same time, but nothing else could fully explain these changes. Details of this analysis can be found at:

        3. Glen K bought up this:- You should note that the graph is noisy, as in there are unexplained spikes and troughs of fairly decent amplitude. Also note that the speed limit wasn’t 55MPH in 1950 as the graph indicates. The speed limit became 50MPH in 1948 and was revised to 55MPH in 1962. If you look at the graph it is flat until 1964 and spiked in 1965 when the Vietnam war started in earnest, so the speed change in 62 made no discernable difference. If you look at 1973 you see a similar tumultuous period. In 72 North Korea attacks the South and the US Napalms Vietnamese villages to discourage them from cooperating with the Viet Cong and Watergate happens. In 73 the US starts withdrawing troops from Vietnam, POW’s are released, cease fires are made and broken, Cambodia and Laos are bombed. Nixon is investigated. So, communism is winning and the US is falling apart. Then at the end of 73 the oil shock happens and petrol shortages happen. Everything becomes more expensive. By 76 the country is in an economic recession. If you look at the graph from 79 to 87 you see a rising trend that continues unchanged despite the change in speed limit in 85. In 87 the upward trend breaks and goes into an inexorable decline despite the increase in the speed limit. If you want to know how deeply 73 affected NZ’s collective psyche look here ,note that NZ’s population growth went into a nose dive in 73 making a low in 79. People must feel comfortable with their future to have kids. One of the effects of the oil shock was the light weighting of cars. The late 70’s early 80’s was the transition of small Japanese cars to FWD. Some appalling cars entered the market in the early 80’s. One whose manufacturer shall remain nameless couldn’t get their vehicle to pass the frontal impact test. they were getting too high a head impact acceleration result in the crash tests, so the moved the seatbelt anchor points so that the dummy would porpoise out under the seat belt, problem solved. Nice your body will be destroyed up to your neck but your face will look nice at your funeral. This period was also when some ridiculously powerful coupes were available. There was also a transition from British cars to Japanese cars. The inexorable decline from 1987 to 2012 can be explained by the engineered safety improvements in cars and roads. The mid 80’s was when the Japanese car manufacturers decided it wasn’t a good idea to kill their customers and started building stronger cars. The 85 Mazda 323 had structural sections some 30% larger than the outgoing model. Wearing front seat belts became compulsory in 75 and wearing back seat belts became compulsory in 89. Airbags were fitted to commodores in 93, ABS in 92.
          In 1950 the population was only about 1.9 million to todays 5 million, also cars cost a lot of money back then and availability was scarce. Car ownership has been consistently increasing on a per-capita basis. Vehicle to vehicle interactions have been growing significantly over the years and engineered vehicle safety has stalled. The popularity of tall vehicles and the downsizing of the mid-sized sedan fleet are detractors for engineered safety. When a large sedan (the safest type) is replaced as NZ’s most popular vehicle with a Ute (the least safe type) you can see where I’m going with this.

      2. The whole sale reduction of limits in Franklin is beyond the pale. Reducing the limit from 100 to 60 on most rural roads will increase commute times by as much as 67%. In a rural environment we have to drive to get anywhere or do anything so we tend to drive greater distances than urbanites. For my daily work commute this will add 6 minutes a day to my drive (assuming a reduction from 100 to 80) This is 24 hours a year in the car or the equivalent of 3 working days. How would Aucklanders feel if someone organized a moving block of the Auckland motorway at 60 km/hr every day during their work commute?

        1. ‘How would Aucklanders feel if someone organized a moving block of the Auckland motorway at 60 km/hr every day during their work commute?’

          Someone organised it years ago, it’s all the other commuters on the road.

        2. In Franklin, the only roads dropping from 100 to 60 are local access or connector roads. They shouldn’t be constituting any substantial part of a journey, and if you were using them for commuting you should take the hint to shift instead to the main roads.

          For those roads that are dropping from 100 to 80, you might like to read AT’s information about the ‘Myths and Misconceptions’. Their analysis is a step or two above your theoretical calculations and is based on real-time analysis:

          “Trips reducing the maximum speed from 100km/h to 80km/h on a 10km length of road showed travel time increases ranged from 30 to 48 seconds.”

          It’s a pity you couldn’t experience safe speeds before AT consulted, which is best practice. Resistance to safety improvements tends to fall away when people can experience it themselves and see how much easier it is to turn out of side roads, and how many more opportunities it gives to children and people not in cars.

          People aren’t cycling or riding horses or walking because the speed environment is not safe. That needs to change.

      3. It might be justified for suburbia but what they are doing to Franklin is over the top. In 35+ years driving these roads I rarely ever see a cyclist on the roads, maybe a couple of times that whole time someone on a horse, walkers and runners are a bit more common where there are life stylers on some of the side roads. So vulnerable road users are very rare. I would argue that the verges of the road is not friendly to cyclists use at any speed and the distances mean it isn’t a convenient form of transport. Some of these roads are long, and straight, sealed, and center marked, with passing lanes, and are sparsely populated. If you look at the interactive map you can see how Franklin has been singled out for special treatment for some reason. Most of the justifications on the AT web site are written of urban settings and simply aren’t relevant for rural roads where around half the changes are being executed.

        1. Looking at the map I doubt there would be many if any commutes that were entirely on roads with a reduction from 100 to 60kmh, looks like most arterials are reduced to 80kmh.

          Your increase in commute times looks like an exaggeration, even before accounting for average speeds as opposed to maximum speeds.

          The reason for the reductions are as much to do with protecting other vehicles users as anyone else. Many of these roads carry more than a lot of state highways yet are two lane country roads with lots of driveways, they should never have been 100kmh in the first place.

        2. Thayer doing the same in Rodney Joe.
          This is what happens when you’re ruled by a far off council in an ivory tower.

      4. 19 km each way, 11.4 minutes at 100 km/hr, becomes 14.25 at 80 km/hr. Difference is 2.85 minutes each way. 5.7 minutes per day. 250 working days per year equals 23.75 hours per year. Some of that commute goes from 80 to 60 km/hr and some goes from 100 to 60 so it is likely understated. I’m not saying I’m representative. There are many for which it will be much worse. This will be my personal cost just for the work commute. P.S. I have driven this work commute 15,000 times

        1. Thanks for putting your calculations up for scrutiny.

          Do you mind letting us know the 19 km that you think you are able to drive at a constant 100 km/hr for your commute? In reality, there are intersections, bends, other vehicles, other types of road users, hazards to slow down for. That’s why I directed you to the myths and misconceptions page. You have simply detailed a common misconception with figures. Actual measurements show there’s nothing like this abstract difference in times.

          That’s why research is useful. It strips out the nonsense.

          And by the way, even if you were held up by 5.7 minutes per day, your attempting to drive at 100 km/hr on country roads not suited for the speed is probably meaning that a whole lot of people who would otherwise be able to get their exercise walking or cycling along the road are unable to, and requiring others to drive them.

          You might be putting a full 40 minutes’ worth of time onto the burden of dozens of parents having to chauffeur their kids around.

          But also, to save a life, of course you should return to a reasonable speed. Anything else is simply refusing to live in a socially responsible way. I can’t imagine what experiences can have shaped your mindset that means you think it’s ok to add so substantially to the risk of causing death – and yes the research is unequivocal about this happening with 100 km/hr speeds – just to save yourself a few minutes each day.

        2. Judging from how people tend to drive on rural roads, I’d say an average of 100km/h might very well be accurate.

          But the upshot will be that the road gets closed due to an accident much more often, which will probably cost you much more than 40 minutes.

        3. I drove the road at the usual speed and timed it and at the new speeds and timed it. including all zones, it was 20:13 at the new speed and 15:09 at the old speed. Average was 54km/hr at the new speed and 72km/hr at the old speed. Net effect is an extra 10 minutes per day or the equivalent of 5.2 work days per year. The consultation process has been so thorough that some people are unaware of the changes that are coming their way. Judging by your comment I’d say you don’t drive Rural roads very often.

        4. ‘ I can’t imagine what experiences can have shaped your mindset that means you think it’s ok to add so substantially to the risk of causing death’

          ooooOOOOooo. Nasty.

        5. It’s not an opinion as this is apparently a “fact based blog”. An noone is bullied when they disagree with a “fact”

    2. My street where I watched a young girl get run down crossing the road to the dairy could do with a lower limit.

      The police asked me “was the driver speeding” and all I could say was that no, he wasn’t going over 50km/h when driving through the neighborhood shops on the corner next to the playground.

      If they’d asked was he driving too fast, I would have said absolutely. But the speed limit was 50, so he didn’t do anything wrong.

      1. Not necessarily true is it? You still have to drive to the conditions. If you crash while going around a sharp bend at the speed limit you were going too fast. If you crash into a child crossing a road near shops and a playground at the speed limit you are going too fast.

        1. Much harder to make a conviction stick if they are going below the speed limit though.

        2. It is true, they driver was not charged or even cautioned. The police did give the mother of a girl a dressing down for letting her cross the road unsupervised however.

          Driving to the conditions is only defined in terms of other cars, the law doesn’t consider pesky things like girls illegally crossing the road when the traffic isn’t clear.

          The road code defines the correct speed for conditions as “ you can stop in half the length of clear road you can see in front of you on a road with no centre line or lanes ”. I’m sure our chap could see all the way down the street.

    3. It also doesn’t look that extensive to me. Only a few small areas in the city, and a bunch of streets on the fringe which aren’t quite ‘rural’ anymore.

      Any proper plan will look “extensive” because small residential streets make up most of our streets, and on these it is totally unnecessary to have cars go by at 50 km/h.

      Map is here:

      On the North Shore there are 2 changes within the urban area. The first one is a stretch of Albany Highway which is now within the urban area. The second one is Oteha Valley Road. Someone actually died on that one a while ago.

    4. If the limit was reduced to 30 on the vast majority of local access streets like the ones pictured, but with a higher limit retained on multilane arterials where that is safe, probably no one would be more than 1 kilometre from a higher speed road and no trip would be more than one minute longer.
      In other words, the feared economic efficiency loss from lower speed limits is trivial.

  5. Gotta note that e-scooters have geo-fencing on certain areas. Compulsory speed-limiting courtesy of the GPS system – slowing them down to 8kph or 15kph in parts of the city. Boring, but works well, it must be said. Personally, I’m looking forward to that happening in our cities on main pedestrian routes – the problem is, of course, that it could only work on modern/electric vehicles at present (i think?) and so the only vehicles exempt would be the old petrol engined bangers…

    1. There’s no need to wait for geofencing technology and modern vehicle fleets to have safe streets.

      “main pedestrian routes” – Problem is, that’s not how walking works. Vehicles need main routes. Cities designed well for walking are ‘permeable’ to walking, densely provided with walkable streets, alleyways, off-road paths.

      1. A huge percentage of people cannot be trusted to follow speed limits, think they know better and the rules do not apply to them. But we continue to give out drivers licences to them a anyway. More speed cameras might work as people don’t speed if they know it’s going to cost them a couple of hundred bucks.

      2. Yes. I’m thinking of Lambton Quay in Wellington – massive walking street with footpaths that have the highest foot traffic level in NZ – and yet cars are still allowed down the street. I think Council is changing that to 30kmh, but still, that relies on people controlling their own foot on the pedal. There’s a lot of pedestrians crossing over the street from side to side.

        1. Lambton (+ rest of Golden Mile) has been 30 km/h for years, its (most of) the wider central city that’s being talked about.
          Agree that too much space is devoted to cars, demonstrates the uselessness of WCC which would rather waffle on about how wonderful Wellington is rather than actually do anything. Probably a few more rounds of studies, reports and joke consultations, then nothing will happen … BAU.

      3. Austroads guidelines say 30km/h for situations where there is the possibility of a collision between a vulnerable road user (pedestrian) and a passenger vehicle. That means all roads except motorways. Australians do not know how to make road rules.

  6. The time consuming consultations, analysing the results and coming up with the final scheme was completed about six months ago. The bulk of the required road signs could have been already ordered, and the installation contracts written, except for the final scope concurrent ready for a short tender period and immediate start. It could have been completed by lockdown. Instead we have yet another example of a transport authority, when faced with a proposal to decrease car privilege, that they were unable to stop outright, resorting to scope reduction, and maximising the delay to implementation. 18 months, till November 2021 to install some speed signs on a small area of the city? WTF. On this basis, bringing the whole city into compliance with Ausroad recommended standards will take us into the next century.

    1. A radar detector is most likely money wasted, as by the time the detector triggers you’re usually nicked anyway. Or have to slow down rather aggressively, risking a rear-end collision.

      But sure, go ahead. It’ll make it easier for the rest of us to see that you’re probably not going to be the most law abiding citizen.

      1. Having lived near K Rd for 16 years I am not looking forward to even longer traffic jams now the area is going to 30km/h

    2. Shows your priorities pretty clearly if you are more interested in avoiding speed cameras when you are speeding than small children running onto the road.

      1. Jezza. There are no small children running into the soon to be 80kmh roads where I drive. And if there were 80 kmh will still pulverise them.

        1. My statement still stands, just replace small children with other motorists, cyclists, people riding horses etc.

        2. Have you considered braking? It means that you don’t collide with the object at the speed you were originally travelling at (or maybe you don’t collide with it at all). It also means that the kinetic energy of you and your vehicle is diminished exponentially.

          If your initial speed is reduced it also means that the distance required to bring your vehicle to a halt is diminished (98 m@100 km/h vs 69 m@80 km/h on a dry road with good tyres).

          When that 50 tonne truck and trailer pulls out of a side road 80 m ahead of you (as it did to me a couple of months back) would you rather be travelling at 100 km/h or 80 km/h?

        3. Yes, MFD has covered it too but if you decelerate by 30 kmh in both scenarios the cyclist would definitely have a better chance at 50kmh than at 70kmh.

        4. Strange. Have just looked up the braking performance of my car and it appears it pulls up from 97-98kmh in 37m.
          So in your scenario I’m quite happy at 100.

  7. I would suggest AT install some speed bump on Queen St

    Too often I saw attention seeking boy racers with noisy cars trying to accelerate as hard as possible at traffic light. The speed on some high performance cars can exceed 80kmh on Queen St!

    Image what happen if a young child trying to cross the street.

    It needs some speed bumps and maybe law enforcement.

    1. The speed on my Corolla can exceed 80kmh on Quay St if I really strangle it. Doesn’t change the fact that it’s a low speed zone and should be closed to North-South traffic either way.

      Also, speed bumps might seem helpful when you’re picking one particular use case (slowing down the 2 Fast 2 Furious lads) but it would be stupidly uncomfortable for bus users, who are the only people who should be in vehicles without sirens on Queen St anyway.

      1. Corolla?! Surely someone with the name Buttwizard should have something with a bit more… magic? That makes a loud farty noise?

  8. I support the lowering of speed limits, but it has to be supported by appropriate traffic calming measures so that the natural operating speed a driver feels comfortable at matches the reduced speed limit.

    1. That’s the narrative. But it’s not matched by the science. Things have moved on in our understanding. Drivers here are trained – by the driving culture and even by the Driver License Test Guide procedure, as I’ve blogged about – to ignore their peripheral vision and override their instincts. If such a thing as the ‘natural operating speed’ exists for our streets, it’s been butchered by our driving culture. My narrow residential dead-end street close to a school, lined with parked cars, would have a ‘natural operating speed’ in most cities of about 20 km/hr. Here, drivers try to get above 50 before braking at the end.

      Compare our street environments with similar ones in cities in many other countries, and you’ll find our speed limits are much higher.

      Talking about “being supported by appropriate traffic calming measures” became the establishment’s go-to delaying tactic. A default speed change would create a far better match between the speed limits and what our streets’ ‘natural operating speeds’ would be overseas than what we have now.

      But also, as I’ve written above, safer speed limits lower the DSI, even where it’s a poorly designed road that encourages faster speeds. With enforcement and driving culture changes (as default speeds would create), lowering the speed limit makes a significant difference.

      It’s important to acknowledge this, because the establishment has, at last. They’ve not been able to keep up the facade that built environment changes must be introduced at the same time, because it is irresponsible in the face of the science. Our first responsibility is to improve our safety outcomes so more people can live full lives not cut short by traffic trauma.

      The mindset of setting speed limits to the built environment is not how road safety works anymore. We set the speed limits according to the safety requirements of the users, and we keep the speeds within them through cultural change, enforcement and, as resources allow, by built environment changes.

      Trotting out the myths about “being supported by appropriate traffic calming measures” doesn’t assist. That’s why Auckland Transport has correctly said:

      “Roadwork to a higher standard will take time. This is why Auckland Transport is reducing speed limits as an immediate, cost effective and efficient way to decrease the number and severity of crashes in the Auckland region.”

      1. I agree Heidi, I do however have the pessimistic view we will get the usual response in Auckland. All it will take is a few voices dissenting and AT and council backtrack. The local response to the Te Atatu South/ Flanshaw Rd improvements is vastly negative ( and often ridiculous ” We will now have to walk to supermarket on Lincoln Rd -a 2hr journey!”) . I hope we can bring the public along with the narrative of slow streets and get communities vocally calling for them.

      2. Speed calming is mostly stupid. Speed humps that slow you down only until you speed up again. A pain in the arse for locals who have to drive those roads regularly and hear the brakes and crashes at night. And it costs money. Lower speed limit and speed cameras is the cheapest, safest, most convenient, quickest to implement option. It’s just not politically friendly that’s all, even for parties that campaign on road safety.

      3. ” to ignore their peripheral vision and override their instincts” – Perhaps it’s because I got my license in the late 90s, but my instructor drilled into me the importance of situational awareness and risk assessments before they were needed. During my driving tests (both limited and full license), I wasn’t allowed to wear sun glasses because the testing agent needed to observe where I was looking.

        I can’t say that there was much explicit work on instinct, but thinking of what could go wrong and how you’d react goes some way to that.

        Have things really changed so much in twenty-something years?

        1. Good question. But the turning radii, the slip lanes, the lines of kerbside parked cars, the documented police bias in messaging, enforcement and crash analysis, the media, the requirement in driver testing to drive faster than is required by the road code, and the ‘pedestrians give way to traffic’ type infrastructure have all worked to make changes in the driving culture.

          Drivers seem to me to be far less tolerant of having to stop behind cars turning, to slow properly to turn into roads, to slow because they’re having to pass parked cars closely, and to stop for anyone unless who’s not actually on a pedestrian crossing.

          Try this. Stand at a corner – maybe a T junction between two connector roads, or a connector and a small local road – and watch how many cars turning right into a smaller road go over the centre line. I don’t believe that was the case 20 years ago.

          Watch, too, the drivers passing long lines of parked cars. Twenty years ago, if this was the case and the space meant people had to drive close to the parked cars, they did so slowly. It was an occasional hazard. Now it’s a normal street environment, and danger to pedestrians stepping out be damned.

        2. Oh yes, I live on an 8.5m street, and I’m pretty sure a few mirrors have been clipped at the full 50km/h over there.

          It is true that the street design should give some hints as to what kind of environment you’re in, but on the other hand people can get used to anything. Steets like Federal Street, CBD have benches on them and no kerbs, which is a very strong cue that you’re not on a dedicated roadway. But if you really want you can teach drivers to ignore that cue.

  9. Thanks Heidi

    Maybe the government made the declaration and then forgot about it because of the lockdown?

  10. “The difference between 30 km/hr and 50 km/hr really can be the difference between no crash at all, and death”

    Stopping distances are determined by the gradient of the road, among other factors.

    On a steep hill, 30kph downhill may be more dangerous than 50kph uphill.

    So, it’s not so simple. Stopping distances are highly variable at any given speed.

    1. Another big factor is rain. So you’ll have to go even slower on that downhill then.

      And it doesn’t change the difference between 30 and 50. Much of the distance is due to reaction speed anyway.

    2. The original stat that they used to use was if a car hits a pedestrian at 50 km/hr the pedestrian had a 75% chance of surviving, if a car hit a pedestrian at 70 km/hr they had a 25% chance of surviving. This doesn’t jive with the new stats. Remember there are lies, there are damn lies, and then there are government statistics. People just make this stuff up.

      1. What we understand from science is constantly changing because that is how science works. It is not made up, it is augmented by further research.

        Safety research is far more robust than anyone’s reckons. The OECD’s International Transport Forum and Austroads are not lying, and if you repeat the claim, you must provide evidence.

        This blog provides for an evidence-based discussion. If you don’t wish to discuss based on evidence, please find another blog better to your liking.

        1. Read with an ear out for understanding, Joe.

          Those stats you’ve given reflect an improvement in safety experts’ understanding of what speed was involved at impact, compared to the speed before observing the hazard. That’s all. The massive reduction in risk by reducing speeds isn’t altered by this. The full picture is that slower speeds allow drivers to:

          observe more of what’s going on, including in their peripheral vision
          pass over less road distance before their reaction begins
          have more options available for reaction during the crash
          stop in a shorter distance
          slide out of control less

          And the outcomes for all people involved are far less severe.

          The AA tried to argue this same line of reasoning as you. I covered this in one of my posts about their lobbying. The AA had sent a letter to the Ministry of Transport and NZTA, in which they accepted that higher speeds cause more harm. The AA:

          “is not arguing against the idea that lower speeds means less harm from crashes… the risk of death is still considerably higher at higher speeds – something no one could argue with”

          and they tried to create their own speed – risk graph, but they botched it. They failed to apply the actual findings from the research they were attempting to use.

          The criticism of the speed -risk graphs is unfounded, but it’s picked up by the many people who can’t imagine change, and who are allergic to safety improvements. You’re not doing anyone any favours by taking this stand.

          Look instead to the results – lower speeds save lives.

        2. If risk factors are derived from empirical data, there has in fact been a devolution in the ability to produce accurate data. Most cars are now equiped with ABS and so don’t leave skid marks making it more difficult to determine speeds post incident. If data is derived from crash test dummies there are multiple ways that this data is maliable. If the data is derived from a worst case scenario rather than a spectrum of scenarios it will be much more pesimistic than reality. These results don’t reflect the complexity of the real world. Also because crash test dummies have existed for a very long time the science should have been setled a long time ago. Because the results are presented as a hard point and not a range and because the numbers are conveniently whole (x6) there must have at least been significant rounding. They do look and feel like a thumb suck to me. You know if the data had supported the policy that they could be brutaly honest and wouldn’t need to use skewed data. If it was real they wouldn’t have spun the data in their favour. Using DSI figures without a basis for comparason is just bad science. Applying Urban calculus to a rural enviroment is garbage in garbage out and knowing that but doing it anyway is dishonest.
          I drove the route at the new speeds on the WE. I have realised that there are aditional changes that were not on the interactive map. Net result minus one of the aditional zones was from 15 minutes usual to 19 minutes new. It is likely closer to 5 minutes each way with the additional zone. This is clear verification that the Urban calculus doesn’t apply to Rural. SH22 is normally heavily loaded during morning and afternoon rush hours and already regularly chokes. What many locals do is drive around the traffic. The net effect of all the feeders going from 100km/hr to 60km/hr will be to shut down that practice and force all that aditional traffic back onto SH22. That combined with the increased density due to its own slowing down there will almost certainly be more congestion. It makes a mockery of AT’s additional 26 seconds. The additional 60km/hr zones on main arterial routes that were not on the interactive map is an additional dishonesty in the consultation process. An 80km/hr zone that was to transition to 60km/hr as is acording to the interactive map has grown from 1km to 4km. The stupidity of the boundary placement of some zones seems designed to cause maximum frustration. Fancy transitioning from 80km/hr to 60 km/hr at the start of a passing lane. Fancy doiing the same right next to a fixed speed camera especially when people acurrently used to navigating that section at 100km/hr. Welcome to Aucklands latest million dollar camera.
          PS. You know most people stop calling it luck after 15,000 times.

        3. “This is clear verification that the Urban calculus doesn’t apply to Rural”

          Calculus “Joe”?
          Here’s some relevant calculus for you. It applies equally to urban and rural situations:

        4. Vision Zero, Austroads and the ITF are all at least as focused on rural roads as they are on urban situations.

          “What many locals do is drive around the traffic. The net effect of all the feeders going from 100km/hr to 60km/hr will be to shut down that practice and force all that aditional traffic back onto SH22.”

          Excellent. Getting rat running traffic out of neighbourhoods is important. Countries with a clear road and street hierarchy allow people to enjoy their neighbourhoods more and have far better safety outcomes. Arterials, not local roads, should be used for travelling long distances. If you don’t fit on the arterials at the low volume of traffic that you’d prefer, the solution is not to speed through local roads at 100 km/hr or so.

          We need to plan for whole communities not for people who wish to keep their driving experience the same as what it is now.

        5. Missed the point entirely. The only reason those “rat runs” exist is because SH22 is over loaded and occasionally jams up. This means travel times are extremely variable. This unpredictability messes with the ability to plan a trip, say to arrive at work on time. Congestion doesn’t make a road safer. People get frustrated and take greater risks. Increasing traffic density, by both slowing traffic and forcing people to abandon their work arounds, increases vehicle to vehicle interactions and so increases the likelihood of an incident.
          To plan on doubling the size of a town with special housing areas but to invest nothing in infrastructure is the problem. Did you know that before Franklin and Rodney were dragged kicking and screaming into the super city they had the lowest levels of indebtedness of all the councils by a considerable margin. Yet they are very much the poor cousins in terms of services and infrastructure spend. They were dragged into the super city so that Auckland could pick their pockets for its own infrastructure while neglecting theirs. Now Auckland is enacting punitive policy towards their benefactors.

        6. I didn’t miss the point. All the development planned there is terrible for the city in many ways. The members of an average household there will drive multiple times what a new household built in a regenerated transit oriented development will drive. The outcome for the climate and for congestion throughout the city, and for safety and public health outcomes is terrible.

          The solution is not to let them rat run through all the other roads and kill community.

          The solution is to invest in what those communities need, without the sprawl, and to invest in intensification further in.

        7. We finally agree on something. They should have electrified the rail system and build the stations prior to development, and getting that train system reliable and frequent is essential. The sprawl is terrible. Unfortunately, Kiwis are addicted to their quarter acre dream. I must admit it is pretty good, no body corporate fees, nobody interfering in your life, and space. There are going to be some industrial areas so some can live and work local. Hopefully they do.

        8. The assumption is that people will follow the new rules. If SH22 chokes it might conversely cause some of those quiet back country roads to become defacto thoroughfares more than they are now. SH22 is clearly no longer fit for purpose. Changing speed limits will NOT change this. If road loading is a key factor in worsening conditions slowing traffic will have the effect of increasing traffic density. It is actually completely wrong headed.
          If you look at safe systems there are four spokes to the wheel, driver behaviour, road condition, vehicle safety, and safe speeds. There is a failure here to recognise why the system is deteriorating. Which spokes of the wheel are failing? The speeds haven’t changed, driver behaviour hasn’t changed, the road has become unsuitable for the loading, and the engineered safety of the fleet has gone down, but the key factor is the road condition. The special housing areas ensures that a significant number of the drivers on Franklins roads are the same drivers as on Aucklands roads.

        9. Fatality rate for pedestrians doesn’t rise above 10% untill speed reaches 50km/hr (+4, -2 ) according to Davis 2001, Rosen and Sander 2009, Richards 2010, Tefft AAA 2011. Wramborg is 2005 and disagrees with everybody else.

  11. 30kph is too slow a maximum speed for most roads. I look forward to the big backlash when this is implemented including from those on PT. Yes there are good arguments for safer speeds but they should be targeted and not arbitrarily applied across the city.

    1. Yet the needs of people walking and cycling are for 30 km/hr speeds. Children have a right to safety regardless of whether adults can picture how to bring international standards of safety to the transport system.

      What you’ve expressed is indeed what many in the public believe, but not the majority. Roughly twice as many adults support safer speeds as don’t – and it’s not surprising that women, Pasific people, and South Auckland residents have even higher support than the average.

      I think opposition is based on some people’s inability to see the second and third order effects of making the change.

      And although built environment changes aren’t required for slower speed limits to lower DSI, the quickest way for the public to see the benefits is if we bring them in too. For that, we need to ramp up the cheap, tactical changes that can be applied across the whole city.

      This is no longer something the public can discard as “fringe” safety advocates’ messaging; Austroads and the OECD are very much “the establishment”. We don’t get to put a veto on the experts’ rules on safety in other sectors before they’ve even been implemented. We shouldn’t here, either.

    2. ’30kph is too slow a maximum speed for most roads.’

      Given they are not implementing a 30kmh speed limit on most roads it’s hard to see what your point is.

      1. Stu is referring to my article about the need for default speed limit changes, not to the small initial tranche of speed limit changes that AT are doing.

        If you have a look at the Austroads, ITF and Vision Zero guidance, you’ll see that most arterials will need to be 30 km/hr.

        1. Yes 30 km/h is too slow for most roads – particularly arterials, but also most other streets that Heidi would like the limit reduced (of course Heidi would like the speed limit for cars to be 0). There is certainly no “need” for arterials to be 30km/h. 50km/h is a safe speed.

        2. Don’t put words in my mouth, Stu.

          And let’s follow the experts on what’s safe for the arterials, not your reckons. Children are hit and killed and seriously injured on arterials because 50 km/hr is not a safe speed limit.

          I understand it’s hard to imagine anything other than today’s congestion without the chances to go a little faster when the opportunity finally presents itself. But there’s a different Auckland that can emerge when we finally let it. One with less delay for motorists because people are safe to walk and cycle, which they are currently prevented from doing because of the speeds and volume of traffic.

        3. It is nothing to do with congestion. Most of the time our roads aren’t that congested – even if they feel like it some times.

          It is safe to walk now! What the lock down proved as that people just don’t want to! Probably the same re cycling. I was surprised that the day the lockdown finished the footpaths became empty again. It is not like they suddenly became unsafe.

          I agree re cycling needs to be safer just not the gold plated way they are being planned (e.g. $50M for Pt Chev to Herne Bay)

          How many of the Auckland DSIs were in central Auckland and were due to someone driving a vehicle between 30 kph and 50 kph?

        4. “It is safe to walk now!”

          Wasn’t for the pedestrian killed on Ponsonby Rd on 31st May. In fact, we’ve been having a spate of pedestrians being hit in the last few weeks. And this morning in our neck of the woods, Stu, there’s been a serious crash up on GNR in Grey Lynn. Suggestions that it’s a pedestrian hit by a van:

          We have the second worst pedestrian fatality per km walked rate in the cities studied by the OECD’s ITF not because ‘it is safe to walk now’ but because ‘it is not safe to walk now’.

          Get away with your ‘proof’ about what people want. Read the research:

        5. In those cases what speed were the vehicles travelling at? What was the pedestrian doing?

          I give very little weight to any research based on targeted online questionnaires. The results are always going to be skewed as the respondents aren’t randomly selected. Only those with a particular interest would bother responding. Even worse is that the respondents are much more likely to only represent a limited socioeconomic group.
          It is the same with AT “consultation” / “feedback”. You only get the opinions of those directly affected or interest groups. Not the general population.
          For the speed changes AT say that the majority of people support it. But it would be a very safe bet that if a proper scientific poll was done the result would be very different. But then of course the aim of the consultation is just to tick a box, not really listen to the lowly ratepayers.

      2. Thats true. But on Glenbrook road that you said had a high loading it just might be a problem at certain times of the day. I find myself counter flow to the highest volumes most times. Most users of those roads do around 100 and where there is a hill and trucks have to slow there is a passing lane. There are a lot of people upset by the coming changes.

      3. By the way ref. the consultation process, they refused to indicate where the submisions came from. This denied the local ward from guaging public the opinion local to them. I’m picking that it was overwhelmingly negative in the rural districts and they wanted to push their agenda through anyway. Most of the submisions were negative to the change anyway.

  12. I was involved in implementng the photographed 30km/h temporary speed restriction in Tasman. Our speed measurements before and after unfortunately showed almost zero effect on actual travel speeds (49km/h mean speed before, 49.2km/h mean speed after), even after we installed additional threshold narrowings using safe hit bollards. Drivers are an unusual and stubborn beast. To me this example reinforces that piecemeal and isolated interventions are not the way to achieve meaningful behavoural change. There has to be much wider and centralised approach to influencing and normalizing lower speeds in urban areas. RCAs cannot manage this alone.

  13. People will adopt a behavior where they feel safe so their speed and driver behavior will be according to their own perceived risk and risk tolerance. Speed limits and the penalty structure and the level of enforcement are an attempt to alter the perceived risk and alter driver behavior. When a drivers perceived risk and tolerance for physical harm exceeds their risk tolerance for a speeding penalty then the speed limit does indeed become a target or maybe even the limit plus some due to the graduated penalty structure. You can only alter this by attempting to change the perceived risk of physical harm. Shock adds are an attempt to do this. When the advertised risk fails to materialize eventually they cease to work and people become inoculated against further shock adds. Improving the road network quality and improving vehicle safety can have the detrimental effect of increasing perceived safety and to some degree drive worsening driver behavior. Luckily the effect of these is greater than the perceived change. So, this is I think the main driver of improved road safety since the late 80’s. Particularly improving vehicle safety.

    1. I agree with you about shock ads, and think they do create numbness.

      There’s a lot of research into what contributes to a driver’s speed, and you’ve mentioned just a few of them. I gave a link to Glen Koorey’s research on the topic and have explored a few other aspects in my posts, such as the contribution of the Driver License Test Guide to encouraging drivers to ignore their peripheral vision.

      Your statement, “You can only alter this by attempting to change the perceived risk of physical harm” is incorrect and ignores a whole body of research into the social aspects of driving. If you have any evidence to support this view, could you please supply it? Otherwise, could you please abide by the user guidelines and refrain from stating an opinion as if it is fact.

  14. I would also say that any speed limit is a line in the sand. It is essentially attempting to define where an acceptable risk lies. It is not a point where there ceases to be any risk. Government agencies fall prey to the temptation of using so called statistics to try and make this more of a hard line than it is by using made up stats. Like I say lies, damn lies, then government statistics. How could these stats be anything else since accident speed data cannot be definitive. You cannot base good policy on misinformation but you can alter perceptions of risk in the minds of those who blindly accept what you say. Redefining speed limits is attempting to change what constitutes an acceptable risk for society. To define this on peoples behalf without referendum is undemocratic. To use misinformation to justify it is undemocratic. You cannot say that this reflects broader public opinion because most of the people within the circles you run in agree with you. This doesn’t constitute a consensus especially not in the wards.

      1. I have read “myths and misconceptions about speed”. How I know it was written with urban environment in mind is this “Other factors, such as lights, traffic, and intersections have a much greater effect on travel time.” In the rural environment there is no traffic lights, I’m seldom held up by traffic or tractors, and intersections are few and far between. Commute times are by far dictated by speed limits in the rural environment.

        1. On many of the roads marked red on the map it would be rare to get a prolonged run at 100kmh unless you are travelling in the middle of the night.

          Glenbrook Rd as an example carries twice the traffic as SH3 between Hamilton and New Plymouth, your claim that these are quiet country roads is laughable.

          As for the roads with a reduction to 60kmh, you couldn’t find a better example than Ostrich Farm Rd of a road that shouldn’t have a speed limit of 100kmh.

          There’s good reason roads in Franklin and Rodney are over-represented in these maps, they are over-represented in deaths and serious injuries as well.

          In saying that it’s disappointing to see how few urban roads have been reduced from 50 to 30kmh.

      2. I do drive at a reasonable speed for the conditions. I should know what my car and I are capable of after 15,000 time driving that same peice of road. Like I say long and straight roads. School kids take the bus to school. No kid is going to hike 15 km to get to school each day. Cyclists rarely cycle such long distances as a commute either at least not without a shower and a change of clothes at the other end. I wouldn’t cycle that road even if the speed limit was 60km/hr. Having a truck and trailer slide past you would be scary even at that speed with that rough verge. Some 60 km/hr sections are unavoidable as they are in the middle of other sections.

        1. “I do drive at a reasonable speed for the conditions”

          Says every driver, always. And yet our statistics…..

        2. If you drive at 100 km/hr you drive at a speed that international safety experts agree is not safe for the conditions. You have obviously been lucky so far. Many people are not.

          Children do not just go to school. They have lives. They visit friends and go along the road to the stream, or to the fruit trees or bit of bush they like.

          Drivers are supposed to have paid road user charges to keep pedestrians, cyclists and horse riders safe. If this was going to be possible at the increased speeds and traffic volumes we’ve seen, separated paths should have been provided. Drivers have not paid for this, so the speed limits should never have risen, and instead should have been lowered as our understanding rose. This needs fixing.

        3. What about other drivers? They don’t all know that stretch of road the same as you might or may be younger and less experienced drivers. Children often have to cross the road to get a school bus and don’t always have a parent to help them cross. A few others & I used to have to cross on a curve with limited visibility either way on a 100 km/hr rural road to catch a high school bus.

      3. Speed is just one data point for defining acceptable risk. Prevailing conditions is one that apparently doesn’t mater. There can be standing water on the road, fine. It could be dark, having to drive under lights, not a consideration. There could be fog so thick you cannot see your hand in front of your face, don’t worry about it. If your car was built in the 1930’s or has a five star safety rating, same same. If the driver is fresh out of driver ed driving a turbo charged pocket rocket or a veteran in a granny mobile, speed is still the only consideration. Why is this? Speed is easy. those other things are more subjective or abstract. At some point you have to be less cynical and have faith in people. If it is all just crime and punishment, only negative reinforcement is available. It is all stick and no carrot. With these things you can only smash people down to the standard you cannot lift them up. There are two aspects to risk, likelihood of it occurring and consequence of it occurring. Speed sits on the consequence side (and it’s important to have limits) while all those other factor dominate the likelihood side.

        1. Who’s saying speed is the only consideration? The government’s not – it’s adopted Vision Zero, which looks comprehensively at all aspects of road safety. Heidi’s not – she blogs about all sorts of safety issues.

          Speed is a biggie though, because it worsens the outcome whatever other factors are involved.

  15. You can laugh all you like. I drive these roads every day and I’m more likely to be the one holding up trafic. I’m seldom on them at night and I never said quiet. People don’t drive Ostrich farm road at 100 km/hr. Speed limits are imaterial at the bends and intersections where they normally come unstuck because these places cannot be negotiated at the limit so they are negotiated at whatever speed the driver feels safe at. Did you ever think that maybe Franklin and Rodney are over represented because they are rural and people drive a lot more and further. If your stats are deaths per million pasenger miles or just raw numbers makes a big difference.

  16. One effect of slowing traffic is to increase traffic density as cars spend longer on the road between a and b. If Glenbrook road already carries twice the traffic of SH3 imagine that with increased traffic density by almost 70%. This could have the effect of causing congestion.

    1. Slower speeds mean shorter distances between cars, which results in more capacity and less congestion.

    1. You’re making stuff up, Joe. Thinking that your logic matches reality.

      In fact lower speeds assist flow. But that’s based on research, measurement, science – all the stuff you profess to think is lies.

      1. If a car travels from point a to point b at 100 km/hr it will take x time to make the trip and exit the road network. If it travels at 60 km/hr it will take 1.67x that time to make the same trip, i.e. it will be on the road for 67% more time along with all the other cars also forced to spend more time on the road. 100/60 = 1.67. This equals 67% more cars on the road at any given time. It is true that following distances can compress some but cars also occupy space on the road. This means that as flow slows capacity drops. When they put a 60km/hr zone in road without passing lanes it creates a choke point and the capacity of the enitre road drops to that of the 60km/hr section.

        1. That would require a pretty high volume of traffic for that to be a problem. From what you’ve been claiming about the lack of cars holding you up, that won’t be a problem on the roads you are using.

      2. Now that I think about it it is 1.67 x the cars going in each direction. So, it is 1.67^2 or 2.79 times the vehicle to vehicle interactions.

  17. -Deaths and serious injury figures used in Vision Zero are whole numbers which pay no attention to population density or passenger kilometers, i.e. they have no relativity for comparison to other areas, as such they unfairly target rural districts where larger distances are traveled more often.
    -Vision Zero is urban focused yet with over half of its current interventions applied to rural areas. Rural forms a foot note to the urban strategies outlined. “details to be determined”. This makes the rural strategy executed without a proper plan. Kind of a suck it and see approach to how people live.
    -Vision Zero is anti-car. The considerations mentioned are as much about environmental goals and the climate emergency as they are about safety. Vehicles are begrudgingly mentioned last in lists of transport options yet rural dwellers are much more dependent on private vehicles than their urban cousins, so this aspect is also anti-rural. Even though it is anti-car it offers no real alternative for rural dwellers. For instance, it would take me 4 hours to walk to work and 4 hours to walk home afterwards, it would take about an hour to cycle each way, that is why nobody does it. Not because of cars. Since all harm cannot be eliminated without eliminating the private car and Vision Zero’s goal is zero harm its unstated goal by derivation is the elimination of the private vehicle. This would make life in the rural sector unlivable.
    -The statistics upon which this whole fiasco is based remains a black box. I have been thus far unable to find the basis of the risk factors this policy is built on. Considering that the process has been less than transparent and duplicitous about its motives I remain skeptical about its basis.

      1. Thanks Sailor boy. I was referring specifically to the Wramborg’s probability curves. Which are what has been used to determine what is an “appropriate” speed. That term by the way is a loaded term. If you look at all the, your speed is inappropriate, think of the children comments here, you can see where they are going with this. It is despicable and really gets my back up. But I digress. The probability curves, I can find plenty of images but I cannot tell how they were derived. If I look at them I see the same curve displaced 20km/hr twice with the last curve conveniently doctored so that it reaches 100% at 100 km/hr. It looks like BS, and this is what un-named “overseas experts” have used to determine what is “appropriate” speeds. It just smells bad. Cyclist/Pedestrian survival stats are listed as, 32km/hr = 95%, 48km/hr = 55%, 72km/hr = 4% (this on AT web page), Vision Zero it becomes, 30km/hr = 90%, 50km/hr = 20%, 60 km/hr = 5% . If you look at the middle stat in particular it is wildly different. This is what you see when they try to take a balance of risk situation (which is a fuzzy line in the sand) and make a hard line out of it. You know if you travel at 101km/hr you will surely burn and die but if you do 99km/hr nothing will happen to you, all will be sweetness and light, only now the latest flavor of the month has become 60km/hr.

      2. Also these curves will be what has been used to determine lives saved figures which is the key justification for all the upheaval they are thrusting on entire reagions. If these curves are what they look like (which is a bunch of baloney) then this is a house of cards built on a foundation of sand.

  18. Anti-car? Bring it on! Cars’ (or users of them / apologists for them) have had far too much freedom to wreak havoc and destruction for far too many decades. Every other industry and most other fields of human activity have had to come to terms with safety-regimes that strive to deliver ‘zero-harm’. Road-transport is long-overdue for a serious overhaul in this regard. And those who argue that their lifestyles are dependent on a continuation of this unsafe-culture need to start re-thinking things. Change-aversion is understandable but unhelpful.

    1. Acording to Vision Zero the bike must be baned from the roads. The deaths per passenger miles of cyclists is off the charts compared to cars. If I run a little physics scenario you’ll see why. If Jaffa Noddy is driving along in his 2000kg SUV wondering where he will get his next latte doing 60 km/hr because he is a good law abiding Jaffa, and collides head on with a cyclist doing 20km/hr weighing in at 80kg wearing lycra and with a little bit of polysyrene straped to his head. Combined momentum calculation for SUV;- (2000 x 60 – 80 x 20)/2080 = 56.923km ie. the SUV suffers the equivalent of a 3.077km/hr impact. For the cyclist it is 76.923 km/hr impact. Relative weight maters big time. If it was a large sedan the cyclist would probably go over the top and suffer a lesser impact. With the SUV he is much more likely to be captured and suffer the full impact. The popularity of SUV’s and Utes has caused a significant deterioration in the safety of NZ’s fleet.

      1. If the SUV was doing 30Km/h instead of 60, the cyclist would be much more likely to avoid the collision altogether.

        1. Slowing the speed from 60 to 30 would double the number of SUV’s the bike was passing. This actually increases the vehicle to vulnerable road user interactions which increases the likelyhood of an incident. Increasing traffic density will results in people taking greater risks at uncontrolled intersections. Gaps in traffic become smaller and fewer.

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