It seems that Auckland Transport have found a use for the large medians they so often like to include in road projects, another lane. They announced on Friday that they would be trialling what they call a Dynamic Lane Control system on Whangaparaoa Road.

Dynamic Lane Control, uses the existing road more efficiently for moving people and goods. It is a travel solution which makes use of Traffic Control Devices and an adaptive LED light system instead of traditional painted on-road markings.

LED lights show road markings that can change configuration quickly and safely, creating an extra lane during peak hour traffic. Traffic control gantries will clearly display which lanes motorist are to use.

Around the world different kinds of Dynamic Lane Controls have been used to get traffic moving at peak times. In Auckland similar arrangements operate on the Panmure Bridge and Auckland Harbour Bridge.

Dynamic lanes are relatively quick to build and cost effective compared to road widening. They allow for the better use of existing road space, accommodate peak period movements and reduce the need to widen roads or build new roads.

AT has been investigating the concept of dynamic lanes on road corridors since 2014. Following a driver behaviour study conducted with the University of Waikato, AT is now aiming to do a full scale trial in the second half of this year.

Whangaparaoa Road, between Hibiscus Coast Highway and Red Beach Road has been selected for the trial, as the road has two lanes with a wide central flush median equivalent to a third lane. This stretch of road has pronounced tidal traffic movements during weekday peak periods. The installation of dynamic lane controls along Whangaparaoa Road would also require relatively low use of surrounding land, which will minimise disruption to residents.

Andrew Allen, Auckland Transport General Manager of Transport Services says “We are currently finalising our investigation and design of an appropriate system to be tested on Whangaparaoa Road. Rest assured that the safety and convenience of the local community will be a key priority for this trial and affected members of the community will be consulted with.”

The results of the trial will determine the suitability and best approach to potentially introducing the controls along Whangaparaoa Road as a permanent feature as well as its suitability in other parts of Auckland.

Some impressions of how it would work are below.

Dynamic Lanes Impression AM

Dynamic Lanes Impression PM

Dynamic Lanes Impression Offpeak

It’s not the first I’ve heard of the idea after AT conducted some online consultation on designs for this some months ago.

On the surface it seems like a good idea. It obviously saves AT from having to expensively widen roads which is good as they don’t have unlimited funds but I can also see a number of potential downsides too, especially if used in other locations like AT say they want to consider. So here are a few thoughts I’ve had about the idea.

  • This section of Whangaparaoa Rd is fairly unique in that it doesn’t have a lot of development either side of it and is unlikely to in the future unless there are significant zoning changes. The section in question is shown in red below

Dynamic Lane Trial location

  • If there are two lanes of busy traffic and no-where to wait safely, how will people get across the road – say to catch a bus. This could be a huge issue in other, more developed parts of Auckland. We’ve seen in the past the inclusion of medians as being justified on the bases that it also provides a refuge for pedestrians.
  • If the idea is used elsewhere, especially in places close to centres, this could also impact on bike lanes or bus lanes.
  • If AT are adding extra lanes through this method, perhaps they should be for the exclusive use of buses and high occupancy vehicles.
  • In this case specifically, what happens when traffic gets to Hibiscus Coast Highway? I assume that HCH is already pretty full in the mornings and opening up another traffic lane might address the Whangaparaoa Rd volumes at the expense of everyone else who uses Hibiscus Coast Highway.
  • AT have said in the past that widening this section of road is a key alternative to Penlink. Given how expensive Penlink is, delaying it would be a positive outcome.

Do you think this is an appropriate idea and where else do you think it could be trialled?

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  1. In this case it’s only 1.5kms, but it would go a long way to removing the evening tailback which stretches to Silverdale. 2 lanes all the way to Vipond Rd. Very positive.
    I wonder if the morning bottleneck will just be moved along WGP Rd from the current narrowed lanes outside the retirement village to the intersection with the HCH? Might need to widen the feeder lane to HCH to avoid this.

  2. About time. Lots more out of the box thinking required to get this city moving. PT will only ever account for so many people movements (most places in the world maxes out around 10%).

      1. But he provides such great opportunities to shut down silly arguments and provide evidence for alternatives to MOAR ROADZ.

        1. Doing something we started doing in the 1970s = out of the box thinking. Lulz.

          Sometimes I wonder it we are all being played by this joker, his comments are just too perfect sometimes!

      2. “Can the mods not block Ricardo’s IP/email addresses?”
        No way Sailor Boy! I get no end of laughs from his “comments.” How can one man be so wrong about everything? It’s hilarious.

    1. FTFY: ‘PT will only ever account for so many people movements if SOVs continue to hoover up the lion’s share of investment. Therefore, we need a balanced transport policy which invests in PT and other spatially efficient modes so we can reach PT’s potential of >50% mode share.’

      Interesting table here, showing that 10% is well below the average PT mode share in cities over 1 million:

  3. How is this any different to the how the Panmure Bridge and Lagoon Drive have operated for 40 years?

    1. It has the word “dynamic” in it :), But its just Tidal flow with the abilty to close off the lane in the off peak,

      It isn’t new and for AT to claim that this is a “trial” is really trying to push it up hill with a rake, its been done in numerous places since the 80s

  4. We have a couple of these in Melbourne. Seem to work ok. Can’t say I’m a huge fan though. Wasn’t there one of these on Pakuranga road?

  5. Having grown up in Pakuranga, where they have used this system on the Pakuranga/Panmure Bridge for eons, I can confirm this works fine. If the trial on Whangaparaoa Road works, maybe they could try similar on Lake Road in Devonport/Belmont. (Yes that would mean closing one footpath on one side and converting it to a cycle lane). There are plenty of roads in Auckland that could benefit from this system.
    I think the idea of reserving the central ‘dynamic’ lane for buses is also a good idea that should be trialled. Maybe start with that initially (once you’ve erected the lighting/signal gantries) and see if that works since motorists will have to get the head around the idea of moveable lanes at first. And in the beginning there are always some idiot drivers who will try to use the central lane for overtaking if they see it empty – that stops after a while when you get a car coming head on at you.

    1. I doubt that Joe Motorist would be over-enthralled with buses dodging in and out of a central lane to access the kerbside bus stops! kerbside is where buses belong

      1. True. I guess I was thinking of defacto expressways where there was a long stretch and no bus stops.
        Given the existing road rules, there should really be no impediment to a bus in the ‘outer’ lane indicating that it wished to change to the left lane, and then into a bus stop.
        But yes, it would annoy motorists – some of whom would ‘rebel’ by not letting the bus shift left.

        1. General traffic lane could move to the centre with left lane becoming a bus lane.

        2. many Auckland drivers are considerate and make space for buses to merge, change lanes etc.

          but then there are black SUVs, Hyundai and Mercedes the worst of them

          just an observation 😉

        1. In a tidal situation like this I agree that the only practical option would be to have the kerbside peak bus only. I was just commenting that in general bus lanes in the centre are a viable option (for four lane roads) and should ideally be the first option for an arterial. AT recognise the benefit of central PT on arterials, however at this stage I have only seen an intention to implement them concurrently with a change to LRT vehicles. However no reason to limit it to LRT (the benefits of central PT running listed by AT on their LRT webpage generally equally apply to buses).

    2. No need to do anything about Lake Road, there really isn’t a congestion issue there. For all that people moan about it, it is extremely rare that it takes more than 10/15 minutes to get from Devonport to Hauraki Corner or vice versa, even at peak times. That’s irrelevant.

    3. The French used to have three lane highways, one lane each way and one in the middle for passing for whoever was brave enough to use it.

        1. And the Brits in the 1960’s.
          I remember the police coming to talk to our class at school and telling us about these roads: “One lane for going north, one for going south and one for committing suicide!”

          It’s amazing how such an obviously bad idea wasn’t recognized as such until long after implementing it all over the place. Makes you wonder how history will view some of today’s absurdities.

        2. the A470 from the M4 to central cardiff still employs this. One of the busiest roads in Wales and far busier then Whangaparoa is very likely to be.

          I’ve never seen an accident there but then again British drivers are significantly safer then us kiwis… even with the far lower speed limits on most kiwi roads.

  6. I think there is a lot of merit in trialling this approach.

    I feel the main impediment could be the effect on turning traffic. Particularly the single lane being blocked by a driver trying to turn across two lanes of traffic going the other way. However (not knowing the road) if there are minimal turning options for drivers along this stretch of road the proposal makes a lot of sense.

    We need more innovative solutions like this, utilising what we have rather than investing in big cost heavy projects.

  7. Whangaparaoa peninsula is fast becoming a traffic nightmare, actually it is one at peak and that is lasting longer and longer, not to mention Silverdale and then at Oteha Valley Rd south. Therefore about now given the growth in the area there should be firm plans in place for mass rapid transport at least from Silverdale. What do we get? A median lane experiment!

      1. Gulf Harbour I think is still expanding, definitely still subdividing mid peninsula and toward Silverdale. I was caught in heavy traffic not for the first, time a couple of weeks back around 8.30 am, literally at crawling speed for two to three kms east of Manly through to the industrial area in Whangaparaoa township. I expected a crash or something but no, the only thing I could put it down to was too many cars!

  8. i don’t understand why so much thought is given to Whangaparoa’s traffic problems. Few colleagues decided to go to leave in a beautiful place (and they remind you that) far away from job and now they are always stuck in traffic. Fuck hem, should have bought closer or not voted National.

    1. Not voted National sure, bought closer? Are you for real or have you had your head stuck in the sand like John Key? Average prices “closer” are $900k! Who the fuck can afford that?!

  9. My parents and I live on this stretch of road. It should help, but I’m a bit disappointed they are essentially removing the median during peak. It is crucial and much needed when turning into and from driveways, especially as that road is so bloody busy all day long. It could definitely cause some grief for turning roads. Also there hasn’t seemed to be an awful deal of consultation with residents on that road. Might have been in order since it is experimental at this stage

    1. Closest I came to a big crash with a customer driving was on Panmure Bridge. Driver coming the other way was in the wrong lane. Fk it was close.

  10. This all seems reasonable enough, a creative solution. Just like roundabouts and slip lanes and clearways and 1->2->1 lanes at intersections and right-turn bans and induction loops and traffic light timing and and and and…

    But we’ve spent decades in Auckland (and beyond) coming up with ever more creative tweaks to the problem of moving as many cars as possible, adding in all these ever more subtle techniques. Whereas the very problem is that we’re applying vast amounts of effort and creativity trying to solve the wrong problem, trying to tweak every last drop out of a system that’s been running up against its fundamental limits for a long time now.

    It would be nice to see some of this creativity go into improving the speed of buses, the dwell times of trains, the safety of cycling, reducing delays for pedestrians crossing roads, and so forth.

  11. The answer is defs use these to create peak bus lanes on two lane + median streets on four lane or more just both direction bus lanes should be put in.

    A) Peak lane curbside lane for local services

    B) If you want it tailored to expresses then median alignment

    Just pick the one that best suits the situation best part is if you change your mind is a flick of a button.

    1. No need for a bus lane yet-hardly any buses! Would suggest a T2 at some stage then a T3 later

  12. hmmmm this raises alarm bells with me. What happens at the intersection with HBC, where there’s only one left turn lane which everyone’s trying to get to in the morning:

    One lane westbound feeding a one lane merge with HCH = queues now
    Two lanes westbound feeding a one lane merge = the same queue, half as long but twice as wide, with no one getting anywhere any faster.

    And cyclists? Currently the median allows drivers to give cyclists some space when overtaking. But with 3 lanes of traffic squeezed into the same road space, cyclists will just get pushed into the kerb. (Obviously proper cycle infrastructure would be the solution, but that’s not going to happen)

    1. Easily convert left turn on to HBC to 2 lanes and the right turn off HBC mysteriously was changed back to how it was pre AT a short while ago.
      Must admit,does make it tight for motorists giving cyclists room but then again I cant recall seeing any on Whangaparaoa Road in peak hours.

      1. There are too many North – South lanes now. Not needed due to interchanges at Millwater and Grand Drive. Dedicated Whangaparaoa Lane onto HCHwy (citybound) to stop the need to merge at high speed. 2 right turn lanes off HCHwy. 1 straight through. 1 into Millwater.

  13. Those large medians are the bike lanes on many roads lacking a dedicated cycle way. Much safer than the footpath I find.

  14. For the life of me I don’t know why it isn’t used on The Terrace tunnel in Wellington. Every morning, there is a stream of traffic trying to go down one lane into the city and very little heading out on the two lanes heading north. In the afternoon, the two lanes are busy, as one would expect, but not overloaded.

  15. I thought the idea of flush medians was that they act as a refuge for turning vehicles (and for cyclist, and pedestrians) leaving/joining the road to/from side streets, driveways, and business premises.

    In the “dynamic” scenario above, if a vehicle wants to turn right, it’ll hold-up all the traffic behind it, and as people try to change to the left lane to avoid the hold-up, the merging will hold-up the left lane also. Will this really improve the traffic in situations where there are side streets, driveways, and business premises?

    Perhaps regular roundabouts will avoid this, by enabling traffic to do a legal U-turn and change direction to make a left turn instead of a right turn?

    1. At least that gets them from blocking up the motorway at Silverdale and HBC Hwy through Silverdale.

  16. Something else they could look at would be installing an East Bound bus lane up the Silverdale off ramp and then down the centre of the bridge (bus lane through the middle of the round about and then down the central median to the park n ride station.

  17. Regardless of location, this looks like a great solution for cars. And maybe buses if they create a bus lane. But pedestrians trying to cross the road to get to the bus? It will be impossible.

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