Every year the NZTA conduct post implementation reviews (PIR) on a small handful of projects. They perform three functions, to see how the outcomes compare what was expected before the project was built, explain any variation in those measures and identify lessons that can be learned to improve other projects. As you’d expect, the PIRs often throw up some interesting insights into projects and we’ve covered a number of these before. Here are some of the interesting points I’ve picked up from the latest batch (for 2015/16).

SH1 Victoria Park to Newmarket

This actually covers four projects, the Victoria Park Tunnel (VPT), the Newmarket Viaduct replacement, Greenlane auxiliary lane and some ramp metering. The PIR notes they “were reviewed together because of their proximity and interrelated influence on SH1 motorway traffic“. The VPT was the first of the governments Roads of National Significance to be completed, in part because already considered a high priority project and so much of the work needed had already been completed.

The summary confirms that while more vehicles are being moved by the increased capacity the projects provided, the initial time savings have already disappeared, a comment noted numerous times in the document. This is also significant as they note that the original economic evaluation forecast that travel time savings would account for 72.6% of all benefits. Positively, Safety has improved though with crashes down noticeably and these weren’t counted in the assessment as “were thought to be low“.

Here is one of the travel time summaries showing that trips are now slower than before the projects.

Overall the costs of the project were less than expected which was mostly due to VPT which was completed months early.

Finally, there are a number of lessons learned listed. I found these three the most interesting, particularly the comments about not making VPT 4 lanes.

Auckland Integrated Fare System

This is the HOP system. On the project outcomes, the NZTA essentially claim that it is too hard to determine any benefits. This is in part because HOP has been just one of many improvements we’ve seen in recent years which is contributing to ridership growth.

One interesting comment about the forecasts notes that the original evaluation assumed that integrated ticketing would boost ridership by about 1% and that fares would add another 1.5%. Given the excellent growth that has continued to occur, it wouldn’t surprise me if that was much higher.

In their response to the findings of the review, Auckland Transport disagree with some of these comments, make some good points and highlight some interesting facts about HOP. They note that:

  • Over 1 million HOP cards have been sold against an initial forecast of 350k.
  • The system was designed to handle 500,000 transactions per day but is regularly doing 70-90k more than that.
  • They note that they benchmark operating costs against Transport for London’s Oyster card. They say using the measure of operating costs versus system revenue, TfL manage 8.8% while AT sits around 9%. I recall the Northern Gateway toll road is something like 30% so AT aren’t doing too badly.

Perhaps their best response is to the comment about bus travel times, effectively saying that without HOP, times would be much worse than they are now.

The Northern busway runs to two-minute interval timetable at peak times how would that be possible with a paper ticket system where each sale takes at least fifteen seconds and the bus loads both at the front and back of the bus.

I quite like this side of AT defending themselves, they should do it more often.

At $99.2 million, the costs of the project were quite a bit higher than expected (38%) and they say that was mainly due to scope changes made by the NZTA. The project was also two years late which is attributed to both scope changes and dealing with the Snapper debacle.

Matahorua Gorge Realignment

This project realigned 4.5km of SH2 between Napier and Gisborne, shortening it by 1.4km. This includes a substantial bridge across the gorge and a new crossing of the since mothballed rail line. They say the proposals for the project have been around for over 50 years and that it’s been assessed multiple times in the 20 years prior to being built. The project was one the government accelerated in 2009

The PIR makes a number of fairly critical statements about the assessment of the project, especially the forecasting, which it calls “basic”. This modelling included using a base level higher than the actual counts and using way overoptimistic growth assumptions.

The main reason for the growth in recent years appears to be due to the mothballing of the rail line resulting in more trucks on the road

On top of this, travel time savings, while good, haven’t been anywhere near as strong as was forecast with an average of 2 mins 37 seconds vs 4 mins 18 seconds.

The most positive aspect to the PIR though is the cost. Initially expected to cost over $31 million, it ended up being built for just $19.7 million

Kamo Bypass Stage 2

As the name suggests, this bypasses Kamo which is in the north of Whangarei and like a few other projects in this post, includes a crossing of a rail line (although this one is not grade separated). It follows Stage 1 was completed in 2005.

Like other projects, it appears that the travel time savings forecast, which were a significant proportion of the assumed benefits, haven’t eventuated.

In addition, the project cost more than expected and is having a number of issues which have required remedial work, including already having to be resurfaced.

Ohingaiti-Makohine Realignment

This was another realignment project that also involves crossing a rail line (grade separated). It was primarily built to improve safety in an area with a high crash rate but improving travel times was a factor too. The new route is shown in red below.

The NZTA say the project has been successful in reducing crashes with all crashes reducing from 42 in the 5-6 years prior to construction to just 7 in the ~4.5 years since. Injury crashes reduced from 10 to 4.

Travel time savings were also seen but times are now back to what they were before the project, which the review says can’t be explained as there has been no changes in the area or significant traffic growth that could have influenced speeds.

As for costs, the project was completed early and $1.3 million under budget for a total of $13.6 million.


One of the most notable comments in all of these PIRs are those about travel time savings, or the lack of them. That’s important as so many projects are justified based on travel time savings and yet at best they’re gone within just a few years. How would it change what projects we built if we didn’t include travel time savings?

What is good are the improvements in safety many of these projects have delivered. I wonder what could be achieved if instead of spending billions on low value motorways, we instead focused say $1 billion of that on safety improvements. The NZTA could probably deliver 50-100 of the types of rural state highway projects shown above which could contribute significantly to improving our dreadful road toll.

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  1. Interesting, whenever I bring up evaporative travel time savings on road projects the usual response is “but it’s really about capacity/resilience/reliability/something else”.

    Well apparently not if the BCRs are built on 3/4 of the benefits coming from travel time savings.

  2. Interesting. Urban projects are most likely to have induced traffic kill travel times savings faster than rural ones. It would be useful to see more PIRs of urban road spending.

    Travel time savings are the main foundation for the economic justification for transport investments. They look a lot more illusory in retrospect than are often so confidently predicted. Of course the fact of induced demand has always been largely ignored in this context.

    Perhaps it is time to review the whole economic evaluation process and consider putting much more weight to the realities of safety and long term environmental costs…?

    Surely no one wants multiple billions of dollars of tax money spent every year in the hope of benefits that either don’t arrive, or quickly evaporate?

    1. “Surely no one wants multiple billions of dollars of tax money spent every year in the hope of benefits that either don’t arrive, or quickly evaporate?”

      Well, no one apart from the CEOs of some large contracting companies and the ministers they lobby.

      1. The most telling pint for me on the SH1 work was that heavy commercial vehicle movements have gone up 8% – 4x – 8x the increase in smaller vehicles.

        That tells the real winners from that work have been the trucking lobby that has this government’s family jewels gently nestled in their hands, ready for a good squeeze whenever MOAR ROADS are needed.

        I would love to see more information on how often Ken Shirley and other trucking lobbyists meet with the transport minister and also party contributions by trucking companies. All the evidence points to these trucking lobbyists being behind most of National’s transport policy.

        The East-West link and the abandonment of BCR requirements for RONS are the biggest indicators. Meanwhile everyday commuters are convinced that the NLTF manages to pay for all roading and is user pays while rail is some bottomless pit of government subsidies. Facts tell us the opposite is true.

        1. Additionally and ironically, or similar, a good amount of heavy vehicle increase on certain roads is actually truck movements caused by the massive State Highway over-build. Huge amounts of spoil then fill is being shifted around AKL at the moment because of the RoNS…

        2. I agree that Ministers Bridges and Roads and Joyce by maintaining their belief that these investments in roads make sense are shooting themselves in the foot. But they are extremely clever guys and I imagine that they have a strategy: either that continued shooting will inflict such pain that it will cause them to miss; or second that continued hits reduce the size of the target again causing them to miss.
          What other rationale explanation can there be for National to pour money into a hole that will make the mythical Labour budget hole assume the significance of a pinhead?

  3. I’m not a genius, but surely the correct way to assess whether a given project X achieves Y travel time savings is to ensure that at least one variable i.e. traffic volume is consistent – the project is designed to achieve the goal in a given environment.

    An analogy:
    We have a plane that can carry 100 passengers at an average of 75kg
    We design a new plane that can carry 200 passengers at an average of 75kg
    By the time the new plane is built, people have got fat, and now weigh 100kg on average
    Thus the gain is not 100 passengers but rather 50 passengers.

    It’s not the plane that was at fault, but rather external social changes outside the control of the plane designers.

    Alternatively, if we assume “inducted demand”, then the benefits might be flat travel times with greater throughput

    1. I’m not a traffic engineer, or very good at maths to be honest, however I’d expect that they’d have used differential equations to account for traffic growth projections. The same projections that are always overly optimistic…

    2. Agree, given this stretch of motorway is the core of the network it will be heavily influenced by what happens elsewhere. The most relevant comparison would be with what travel times would be in 2016 if these upgrades did not happen.

    3. One of the problems is predicting what growth in traffic volumes would occur if we do the project vs if we don’t do the project. Maybe this is why the models tend to ignore induced demand because it makes everything simpler.

      However because induced demand is a result of the project being built rather than an independent societal change a better plane analogy would be:
      We have a plane that has room for 100 rather uncomfortable “narrow” seats.
      We design a plane that can hold 100 much more comfortable “wider” seats.
      Because the new seats have more space everybody eats more and gets fatter.
      The seats are now no more comfortable than when we started.
      Thus making it highly questionable if the new plane has achieved any net improvement in passenger comfort.

      1. Yes but this blog tends to assume that all traffic growth is due to induced demand instead of population growth.
        Also there is no mention of the positive economic impacts of more people making more journeys.

        1. “Yes but this blog tends to assume that all traffic growth is due to induced demand instead of population growth.”

          In an urban peak hour this is probably true. The network is at capacity, so trips can only occur with increased capacity. The question is then ‘what is the most efficient way to add that capacity’. If the answer is more cars, then you should check your working.

        2. +1. Equally, by NOT building increased road capacity, by boosting public transport alternatives, and perhaps even restricting road capacity, it has been well-demonstrated that traffic de-inducement can occur.

          People simply adjust their transport behaviour based on their knowledge of the choices available to them. If they suspect that gridlock will be occurring at a certain place on a certain day, many will opt to modify their plans and avoid it. As a result, traffic can melt away just as easily as it can grow.

          Why is the private-car mode-share in London now down to 31%? Answer, because the city has ceased to prioritise the accommodation (=encouragement) of private traffic and has boosted alternatives.

          Not rocket science.

    4. The problem with trying to see greater throughput as a benefit is that it also entails greater feeder road traffic volumes. The induced traffic from motorways like these translate to more traffic throughout the whole network, including in the streets we call home, where children are playing and cycling, etc.

      While NZTA can show reduced travel times, they can claim diversion away from some areas of the network (but there is also actual increase in others). When there are no reduced travel times on the length of the project itself, and only increased throughput, the result on the city’s network consists of increases only. They can make no claims of traffic diversion from local roads to the new project.

      1. And the other misleading factor about using traffic-throughput as a measure of efficacy is that it takes no account of the *value* of each journey. If half of the journeys made through an expensive piece of roading infrastructure are being made for trivial reasons only and could easily be made by another route, another mode, at another time, or not at all, then it begs the question, was the expensive piece of roading infrastructure worth it? But the value-of-journeys is never seriously considered in the assessment of schemes. Only straight traffic-numbers.

        Would those frivolous users still make the same journeys if required to pay a toll towards the provision of the scheme?

        Interesting how concerns about tolling the new Transmission Gully motorway are that few would pay to use it. If its value is less than people are prepared to pay to use it, should the govt be spending $1bn on building it? Or by extension of the argument, why not make the parallel train service free also?

        1. Well said – I reckon the EEM needs a whole lot of work in this area.

          If a person will make a trip if it will take 10 minutes, but won’t make that same trip if it is going to take 12 minutes, you have to question how valuable that trip really is.

          I suspect this is a bigger issue than the innaccuracies around predicting numbers of induced traffic.

        2. Equally if a person will drive if the drive takes ten minutes, but will walk if the drive takes 12 minutes we have to ask whether we should be increasing driving speed if the only result is a reduced life expectancy for that person, more pollution, more greenhouse gas emissions, and an increased chance of that person killing someone else.

        3. Also we know. Like really know, like for sure, that a whole bunch of those trips will just disappear (not happen at all, shift to other times, other modes, if provided) with even the smallest additional cost in time and or (especially) money.

          So what on earth is the real societal value of inducing them as car trips?! This is un-measured but vital. Current metrics are so basic especially in as much as they have nothing to say on this wider outcome of creating traffic that is likely needless, with all the associated societal disbenefits of this.

  4. I wonder how much of that 45% reduction in crashes through Victoria Park-Greenlane is down to two things that aren’t part of the reviewed projects: moving Nelson St from the right to the left, and reducing the speed limit through CMJ to 80km/h. Those are the only actual changes that affect the safety of that stretch of road, and my memory has them both occurring around that 2009 point.

    1. I think all the work through CMJ to make the lane counts all match up better etc were good projects combined with the on ramp lights making the flow more consistent have really helped with accident rates. Don’t forget that Auckland’s road “population” has really increased in these years. I quite like how the Victoria Park Tunnel was quite clever turning the existing north overpass into extra southern lanes. Just hope they don’t widen pretty much anything more in that area.

    2. My understanding was that lowering the speed limit to 80 km/h actually increased the capacity of a highly congested road due to much less stop-start behaviour. Is this a factor here?

      1. I don’t know if the harbour bridge has always been 80, or if that represents a change. If it’s a change, I’d expect that to have happened in response to concerns about it’s longevity.

        The same concerns that resulted in Grafton Bridge being restricted to 30k – Kinetic energy (KE = 0.5 x mv2). In English, a given object moving @ 15m/s (for example) has only 25% the energy of an object moving twice as fast. This is also why small changes in impact speed have disproportionate changes in damage done.

        1. I’m pretty sure that the harbor bridge has always been 80. It was posted at 50 mph when it opened and has been at 80 km/h as long as I can remember (2003). The Bridge has a lot of lane changes, high traffic density, and narrow lanes. Even if the structure could support 100 km/h it is unlikely that the bridge would ever have a higher speed limit.

        2. While I don’t know the answer, it’s worth noting the national open road speed limit was 50mph in 1959 when it opened. I also believe there was a time when there were only three mandated permanent speed limits in NZ – 50kmh, 70kmh and 100kmh, could be wrong though.

        3. I have always understood that at some point the speed limit was raised and then reduced again – I thought it was due to crashe rates. However, google is not particularly forthcoming with any information to confirm this.

        4. I’m pretty sure that the speed limit on the bridge was 40 mph when it opened, not 50 mph. Does my memory fail me?

      2. No it doesn’t work quite like that. A road carrying more traffic will flow slower. The speed reduction is caused by having more vehicles closer together. But a road with a posted speed of 80km/h should have the same capacity as a road posted at 100km/h that has a high enough traffic flow to reduce its actual speed to 80km/h. Modellers get carried away with speed flow curves for different types of road but it is a bit artificial. At capacity they converge and are controlled by the capacity at intersections and ramps not the link itself.

        1. Cheers mfwic. I understand that at capacity flow is equivalent regardless of speed limit (above a certain limit). However, is it the case that flow breakdown is more likely to occur when traffic volume is approaching capacity when the speed limit is higher?

          As an example. Say a two lane road has ultimate capacity of 4,800 vph. With traffic travelling 110 km/h flow breakdown might occur at 4,000 vph. With traffic travelling at 80km/h flow breakdown may occur at 4,400 vph. With flow breakdown taken to mean the occurrence of ‘shockwave’ traffic jams from sudden braking downstream.

        2. Yea I thought lowering the speed limit could increase throughput – isn’t that the whole idea behind variable speed limits on motorways?

        3. Traffic ought to be at around 60 to 70km/h in either case so it shouldn’t matter what the speed limit is signed as. The sign acts as an upper bound or a kind of loose upper bound. Where there can be differences is if an authority has set a policy that all 100km/h roads are designed differently which might mean you get different capacities but only because of the physical nature of the road not the limit itself. It is one of those endogeneity issues to look out for.

        4. chrism I think they are more an issue of trying to prevent incidents when some clown hasn’t figured everyone needs to go slower. But you can’t lift the whole curve through regulation.

        5. Cheers for the explainer mfwic. I find some of this stuff at the limits is really complex to wrap my head around. The steady states are easy, but often aren’t the problem.

    3. I am not convinced that moving the Nelson St off-ramp had much impact on safety. I will look into it when I have time. The late Russell Dickson once showed me an analysis he had done that showed it actually had fewer crashes than other ramps. We could only think it was because everyone disliked it so much they drove with more care. I was amused when a few years later safety became the justification for a project to ‘fix’ it.

      1. Interesting. That’s similar to the Shared Streets theory that you so dislike…

        Purely selfishly, I always liked that right hand off ramp as it is the best way to Ponsonby and meant when driving home from the south I just got into the right hand lane at about the Bombays and stayed there till i found myself in Freemans Bay… of course I prefer it as it is now, and use it a lot more in its current en-pinked state…. so win win; traffic engineering follies that we can repurpose are handy, but I’d rather we just design our cities better from the start (i.e. not just as irritants for the providers of rural highways).

        1. How can someone dislike shared spaces? They are effectively a pedestrianisation that allows vehicle access to driveways. We just need to prevent through traffic now…

        2. Well you’re right about “purely selfishly”… nobody should be sitting in the right hand lane for 45km!!
          The law in NZ (as is other countries or the opposite side of the road) is to keep left unless passing. Now you may have been passing however I find that hard to believe over a distance of 45km and based on your publicly stated objection to people speeding (which you would have had to have been doing if you were passing people for 45km since even during peak times there are plenty of sections where traffic still flows often above 100km/h).

      2. I suspect the Nelson St offramp induced a fair bit of newbie traffic on the bridge (Newmarket to Western Springs via the North Shore.) Self-explaining roads and all that.

  5. travel-time savings have evaporated due to increased demand? It’s almost as if people’s land use and travel choices respond to investment in transport infrastructure. Hmm — now there’s a thought!

  6. “Why do they say the original modelling was spatially limited and therefore unable to forecast wider changes”, etc. I’ve not read the traffic modelling report. Did they not use their usual method of working out the expected traffic from ART3 and then assigning it?

    1. OT but OK: My view is the Puhinui site on the Manukau makes the most sense for the benefits side: close access to Auckland industry (primarily in the south), close location to logistics hubs around airport and wiri, access to the main trunk railway without passing through central Auckland, access to both motorways, next to a big chunk of future industrial land under the flight path… and on the right side of Auckland for access to the Waikato and Bay of Plenty, It’s also well positioned for ship linkages to the southern North Island, the South island, Australia and Asia.

      The main issues being the cost of creating the artificial island and dredging the Manukau channel… but any option, including the existing, will have similar costs.

    2. OT but so closely related to the motorway and traffic topic really. All those trucks going from the port to logistics companies near the airport… great for making air freight cheaper than sea freight but is that in the interest’s of the planet? So we scramble to provide the transport infrastructure to the airport precinct for all that freight and all those jobs. But who made this huge land and transport decision?

      1. I think that Puhinui makes a lot of sense. It would be easy to connect HR for freight if we don’t need to worry about connection to passenger network. We can basically go straight from the Wiri yard.

        This will significantly reduce passenger/freight conflict in future. It will also allow easy freight connections to the Hamilton inland port, and to the south.

        We would also need to construct an inland port somewhere near Kumeu to service industry in the North and Northwest.

        We still have the issue of the massive dredging that would be required though…..

  7. It’s a good point regarding safety outcomes from all these projects. It’s out speed focus and almost obsession in NZ that has skewered our project priority. The speed savings evaporating seems to be a surprise in these reports findings. I guess there were more PIR’s? than the ones you picked Matt? The recommended speed increase for the Kamo project is interesting with “…and needs to be addressed.”

      1. I keep hoping it’s a statistical blip but it appears otherwise. I’m so sorry for all the families involved. It feels like we’ve reached some sort of tipping point in the psychology of rushing and in building roads to help us do so…

        1. I thought 2016 was a blip, but we are really looking at erasing a lot of the good work since the turn of the millennium. We really need to look at where and how these deaths are occurring and target a lot more investment there.

        2. I’d say the last few days are probably an anomaly, however the overall trend is a problem and means there is more chance of this anomaly happening again.

        3. +1, and an increase in annual road deaths make the worst week in any given year worse than the worst week in previous years.

    1. I agree safety outcomes are important. Any analysis, of course, will have to appraise the safety across the network. Our motorway expansion programme has resulted in traffic growth throughout the city, resulting in safety decreases in the local roads. So it’s important an analysis doesn’t just look at the safety in the short segment of the project in question.

      1. Yes, so many studies on everything have such a narrow focus that I wonder how useful they really are. On the other hand, how to you encompass everything that a project affects?

  8. These evaluations all operate as if in a closed system. As if there are not alternatives that could be provided to move the proportion of newly induced traffic in cities. These alternatives may well have lower cost, lower wider disbenefits, and higher benefits, but are never evaluated as options to highway super-sizing. NZTA currently is not really a true transport agency, but a road builder, and largely a rural road builder, even though many of these country highways are in our cities. This is way out of date, and needs to change.

    1. Way out of date, and it is not as if the people involved couldn’t know the deficiencies in their models and evaluation systems. It’s very well researched.

    2. Hear, hear. The way I read it we spent $650m in order to move 1-2% more vehicles (and therefore probably 1-2% more people) across the bridge more slowly than was previously the case. What else could we have done with that $650m in the public transport realm that might have moved more than just 1-2% more people – and at the same created a lasting asset with spare capacity for future growth.

      If it were up to me, the radical solution for the harbour bridge, future light rail tunnel notwithstanding, would be to sequester the two easternmost lanes of the bridge for a 24/7 busway and extend the busway right into the city. General traffic would have to live with 6 lanes, but people would very quickly realise that it was much more efficient to use the bus and a new equilibrium would be established. Carrying more people than now faster than now (on average) across the bridge. What’s not to like about that?

      Ooops, sorry, I forgot. That’s social engineering. Smack hand!

      1. I’d be looking at making one lane in each peak direction a bus way, while the direction was set at five lanes.

        There would be issues for the counter peak flow, but this blog has already highlighted the issue and I’m not expecting it to get any better until a dedicated Transit link is built.

        1. As I suggested, there would be a need for new travel patterns to emerge, especially with counter-peak flow. But the time has almost come when we have to say “absent serious investment in PT infrastructure, we are going to have to take more radical measures to ensure the harbour bridge doesn’t grind to a halt. Yes, it will cause some people some pain until they figure out that there are alternatives that they can use, but fundamentally, the greater good is served by allocating a scarce resource (ie a traffic lane) more rationally.”

    3. As an addendum to my previous post, it really irks me that we have poured huge amounts of capital into a travel mode across the bridge that is experiencing more or less static growth, yet completely ignored the travel mode that has been growing at around 15% plus year-on-year for many years. Surely this must give pause for thought to the right-wingers who espouse economic “rationality”. If it was a business that they were being asked to invest in, would they choose the growth opportunity over the mature market? If not, then it just shows how corrupt and predetermined these outcomes are. Which is, of course, what I’ve long assumed anyway.

      1. The response I’ve heard to that is “we need to invest more in the roads to stop all the poor commuters being forced out of their cars onto the bus”.

  9. Sneak preview of the SH16 upgrade PIR:

    Took a long time
    No difference made to travel times
    Should’ve built a busway (or at least provided for it)

  10. Greater Auckland, Europe, United States, China, Japan and New Zealand, now try have a biggest fight to get all the money out from 25 Country: Brunei, Cambodia, East Timor, Indonesia, Laos, Malaysia, Burma, Philippines, Singapore, Thailand, Vietnam, Southeast Asia, South America, (Central America), Melanesia, Micronesia, Australia, South Asia, Western Asia, Central Asia, Africa, Hong Kong, Macau, Taiwan and Mexico into 5 Country: Europe, United States, China, Japan and New Zealand for every month.

        1. What a good idea. We could make a pack of cards from all the unusable transport cards:
          – those blacklisted for auto-top-up going wrong;
          – the children’s cards that can’t get a concession loaded;
          – those forever linked to the parent’s account even though the “child” is grown up and independent;
          – the snapper cards that can’t get converted any more.

          Not sure what game we’d manage to play with them. Probably just build affordable houses of cards… But yes, we’d play it on the bridge when we have a car-free day.

  11. I wish cycling projects were subject to the same criteria

    Time – Travel time much longer than before regardless of previous mode
    Cost – Hideous given the numbers using the project
    Crash Rate – About the same but higher hospital costs due to lack of protection whilst riding a bicycle
    Social – You smell bad and develop a sense of entitlement and arrogance which puts other road users and yourself at risk.

    1. A’h Matthew, you smell so sweet. Come for a bike ride with Bike Auckland this month. I think you’d stretch your muscles and breathe deeply and giggle with delight.

    2. Good one! You of course forgot induced traffic as this is the primary justification.ie build it and they will (maybe) one day come (if it is not raining).

      1. I must have imagined that rain on my ride to work yesterday :). Cyclists never cycle in the rain, so obviously I gaslighted myself.

        And obviously I am the entitled one, not the motorist who was double parked this morning, or the one who beeped the horn, gesticulated threateningly, and then swerved at me for feeling so entitled as to legally ride past the double parked car when other, obviously less entitled, people were also using the road.

        And obviously the $11m for 1,000 daily users ($11,000 each) on the light path is outrageous compared to the $1,400,000,000 for 20,000 daily users forecasted for Puhoi-Warkworth ($70,000 each)

  12. I hate these stupid posts. Always ruins my day to hear how much of my tax money was wasted on this crap that achieves nothing NZTA said they would. Need more investment into other modes darn it!

      1. The opposite. More capacity means less traffic on local roads. Think back to pre CMJ project and getting from North to North West.
        I cant see how anyone can think CMJ, VPT and Newmarket viaducts were not very successful projects.
        Just think how bad traffic would be without them. While normal travel times probably haven’t reduced they haven’t got worse despite the natural increase in volume.

        1. No, Stu. Extra road capacity initially decreases congestion. This can draw traffic from parallel routes, as you say. However, the overall number of trips goes up. Not enough, for a while, for congestion to be as bad as it was. In some areas, the traffic volume increases, such as in lower-volume suburbs where the roads cannot form a parallel network. In these places the extra traffic is due to people making use of the lower congestion in the areas that are “parallel networks” to the new project. These extra trips – whether in the lower congestion area or in the higher congestion areas – lead to changed driver behaviour: more use of the car for lower value trips. This is the stage the Waterview Connection is at: lower congestion in many areas, higher congestion in a few areas, and overall higher trip numbers, rising all the time.

          Over time (in the case of the VPT, not very long, as matches the research into heavily congested urban areas) the number of trips increases until the congestion is similar to what it was before (exactly what happens depends on other factors and projects in the network.)

          The point is, the increased number of trips all started somewhere, and ended somewhere. Those “somewheres” were local roads, places where people live and play and cycle. The VPT has become, and might remain only as congested as that strip of motorway always was. The Waterview Connection will follow suit in a few years. But the local roads where the trips started and ended – these will have increased traffic. Permanently increased, unless road reallocation is allowed to occur.

          Stu, you’ve been reading long enough to have been exposed to these ideas. I’ve taken the time to spell it out here. Do you need me to post references about how adding road capacity increases traffic? It would be really helpful if you accepted what the research says on this so you could be a helpful critic for matters where the research isn’t settled.

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