By now I’m sure most have seen the news about the Auckland Harbour Bridge being damaged after a 127 km/h gust of wind blew over two trucks, including one that hit a load-bearing upright strut on the superstructure.

The bridge strut bent out of shape after being hit by a truck on the Auckland Harbour Bridge
The bracket where the bridge truss has been sheared away, breaking the bolts holding it in place

As is always the case these days it seems, it was even caught on camera.

This has resulted in the centre four lanes of the bridge being closed to all traffic, half it’s normal capacity and even less in peak times.

Waka Kotahi NZTA say:

“A temporary fix to re-open lanes may be possible in a few days but a permanent repair is weeks away. We’re working on both and working as quickly as we can”

This adds to an already difficult time with the city’s transport infrastructure with the rail network being slowed and partially shut down due to worn our rails. I think there are both short and long term actions we need as a result of from this bridge disruption.

Short Term

The NZTA are calling on people to work from home and/or avoid the bridge, but also alternative routes like the Northwestern.

“While the Auckland Harbour Bridge is at half its usual capacity there are also significant knock on effects across the transport network, with additional vehicles now switching to the Western Ring Route,” says Waka Kotahi Senior Journey Manager Neil Walker.

“We ask people to consider working from home if possible or using public transport instead of taking the car. If you must travel, avoid peak times in the morning and evening and allow extra time for your journey. Heavy congestion and delays are expected on both sides of the bridge as well as other state highways and local roads.”

…..

The Northern Busway will be operating and buses are safe to use the clip on lanes, however buses will be delayed as they join the queues to cross the bridge, so passengers should plan ahead and allow extra time for their journey.

One of the tricky things is that many of the buses that might have otherwise been able to be used are not available because they’re needed as rail replacement buses. Even so, AT say:

We will be increasing the frequency of bus services outside of peak hours so you can take advantage of our 30% off-peak fare discount. Ferries are operating as usual and have spare seating capacity.

We looked into how many passengers we can carry on bus routes that go across the Harbour Bridge and found that:

  • For a Monday morning inbound to the city, 7:00am to 8:59am:
    • The Northern busway has 7000 seats available with normal service.
    • Onewa Road has 2500 seats available with normal service.
  • For Monday afternoon outbound from the city, 4:00pm to 5:59pm:
    • The Northern busway has 6500 seats available with normal service.
    • Onewa Road has 3000 seats available with normal service.

These numbers are for seats only and there is room for about 10% more people when standing. North Shore ferries will be using the largest vessels available, and additional services are on stand-by.

As is noted above, the issue with this is that buses will be caught in congestion as they approach the bridge. While the bridge is already significantly down on capacity, perhaps now is when they should be adding some bus lanes to the bridge. The idea being to really make the PT option work as smoothly as possible to help encourage as many people as possible to use it.

Bus users make up about a third of all people crossing the bridge.

In addition, the NZTA should be adding a Northbound bus lane through St Mary’s Bay. There should be enough space for one from the Fanshawe St onramp through to about the Curran St onramp, which is where the clip-on and centre lanes start to diverge. This would allow those buses to skip about 1km of traffic and frankly should have been done as part of the works about a decade or so ago.

Perhaps AT also need to put in some temporary cycleways on all approaches to busway stations to make it easier to get to them.

Long Term

Firstly it’s important that we don’t over-react. Already there’ve been plenty of suggestions that this proves we need another harbour crossing (for cars). When we think about the long-term implications the first thing we should remember is that this is a very rare event. It’s so rare that it’s the first time it’s happened in 60 years. Something that causes a few weeks of disruption every 60 years, no matter how frustrating it is at the time, is not justification for spending billions of dollars on duplicate infrastructure.

Resiliency is often cited as the main argument for building another road crossing but even if we already had it, it wouldn’t have prevented chaos. Here’s why:

Resilience ≠ Capacity

Having an alternative to the bridge and SH1 was one of the key arguments behind the building of the Western Ring Route (WRR). In fact, the NZTA’s project page says this about it:

Once complete, the Western Ring Route will be an alternative to Auckland’s State Highway 1, linking Manukau, Auckland, Waitakere and the North Shore, improving network resilience, travel time reliability and bus shoulder lanes, and upgrading cycleway and pedestrian facilities.

The WRR does provide an alternative route but it doesn’t and can’t provide enough capacity to cope with the level of demand that it normally handles as well as the bridge traffic. We saw this clearly on Friday.

Any new crossing will result in one of two things.

  1. An overall increase the capacity for crossing the harbour. This will encourage even more people to drive (induced demand) which means that like with the Western Ring Route, any new road crossing isn’t going to have enough capacity to cope with the sudden influx of additional vehicles. In other words the same thing that happened on Friday with chaos on nearby roads would be repeated. More capacity across the harbour is also likely to undermine our other goals as a city as it means an even larger firehose of traffic is pointed at the city centre, right as we’re trying to reduce the number of cars there.
    It’s also worth noting, what often gets overlooked is that this would mean more vehicles on the motorway north and south of where the crossings join/split and also on all of the local roads where adding capacity is even harder. If you use Onewa Rd or Esmonde Rd or any of other roads that interact or are near the motorway, they’ll be even busier.
  2. No increase in capacity. It’s also been suggested that in the event of a new crossing being built, the existing bridge could have space on it repurposed, such as for bus lanes and maybe even bike/pedestrian lanes etc. This would mean there is no real new capacity across the harbour and that the level of demand stays about the same. But that also means we’re still having to accommodate that traffic in fewer lanes than we do now.

In both of these situations we also need to remember that an issue could occur on that new crossing.

Of note, Waka Kotahi Senior Journey Manager Neil Walker says:

The network is one that doesn’t handle events like this well, Walker said.

“You can’t build your way of it forever and we’re going to have to think smarter about how we try and manage demand on the roads, so that’s greater use of the likes of public transport and that sort of thing, particularly around the peak times.”

‘You can’t build your way out of it forever’ – Neil Walker

Not designed to interconnect

It’s not just the issue of capacity that we need to consider, it’s also how the network is designed. The last public designs we saw for a new crossing are about a decade ago now but crucially they show that on the southern side, a new crossing would connect directly into the Central Motorway Junction without a connection to the city centre itself – effectively turning the existing bridge into a giant off-ramp. This explained well in this diagram below.

What this means is that in the event of issues on the bridge, traffic from the city wouldn’t be able to access the new crossing, except for perhaps via Grafton Gully but those streets would quickly overload. It also means that if there was an issue on the new crossing, traffic already on the motorways would have to exit and weave through the city to get between on/off ramps. The city isn’t designed to cope with that and will be less so in the future as we make it more pedestrian friendly as part of the City Centre Masterplan.

There are other forms of resiliency

The best way to add resiliency to crossing the harbour is to have a multiple separate networks, ones that is not affected by whatever happens on the others. Separate networks in the form of Skypath and a dedicated public transport crossing. While there is often little people can do in the immediate aftermath, if we had these already in place then over the coming days and weeks they would have allowed for people to change how they travel, blunting the impact of the lane closure. Note, the benefits of having separate networks applies not just to the harbour crossing but other aspects of our transport network too and is why light rail makes sense rather than putting all our eggs in the heavy rail basket.

One of the most significant examples of this was in San Francisco following the 1989 Loma Prieta earthquake. The earthquake damaged on of the sections of the Bay Bridge and it took about a month to get it fixed.

However, the Bay Area Rapid Transit (BART) tunnels, which cross under the bridge, were unaffected and able to be used the next day, providing the only direct connection between Oakland and San Francisco. Usage jumped dramatically – up 17% for the entire fiscal year and then grew from that in subsequent years. That showed that not only did it provide an immediate alternative but that many people permanently switched to using it.

Back in Auckland, the most recent papers we’ve seen on the topic of a harbour crossing showed that adding another road crossing would increase vehicle trips and make congestion worse, even if a combined road and public transport crossing was built. The best performing option was for a dedicated light rail crossing and road pricing on the existing bridge. As a bonus, it would also be cheaper.

This further highlights that we need to focus on adding the missing modes.

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114 comments

  1. Surely this must prove, in the minds of some of our transport planners, that we really really REALLY need that cycle lane attachment. Just so that one or two mad people per day can ride across the bridge on their sweat-inducing contraptions. Especially on weekends, when they can wear Lycra! Certainly it should not be used as evidence to help justify a second harbour crossing! (do I need to add, sarc?)

    1. Hopefully not too many cyclists will try and cycle across the bridge in 120kph winds….

      Best wishes to Windy Auckland from Benign Wellington…

    2. Well its a cracking day today, I’m sure a lot of people would prefer a 30 minute walk or cycle in the sun over a frustrating hour long trip in the car. Not everyone is allergic to exercise.

    3. I love cycling projects across the city and I fully agree with pretty much all of them. But that 350million price tag is a big pill to swallow. I know this would be years away, but surely build the rail tunnels, remove most of the busses from the bridge while simultaneously using that as an excuse to close the eastern most lane and make that the walking / cycling connection. Build a solid 3 or 4 meter high noise / pollution wall. Use the 350 mil on all the other main motorway corridor cycling connections. Dont get me wrong, I certainly wont complain about the connection, I’m just not 100% convinced it was the best bang for buck solution. And I will admit, the current skypath project looks fantastic.

      1. So how many billions would that tunnel cost again Jack? All because you don’t want to see money spent on separate infrastructure for pedestrians and cyclists.

        1. That is completely inaccurate, I think more money should be spent on seperate cycling infrastructure, and public transport. I just think that given we have a limited amount of money, and per dollar, we could probably grow cycling more if we spent that same money on different cycling projects (like from Newmarket south next to the rail corridor). In my mind the light rail tunnels under the harbour are inevitable and necessary. I suppose we could use the two centre motorway lanes, but that I think that would be a very unlikely sell to people too entrenched in their cars. I concede that the sky path is a much more elegant solution and will come probably a decade earlier than waiting for my proposed solution but still. 350 mil could buy a lot of bi directional cycle paths on the arterial routes like Manakau road, or last part from Tamaki drive to Glen Innis for example.

        2. Jack – the main issue with cycle lanes on arterial routes isn’t money, it’s resistance to road space being reallocated.

          Better to get on and put the walking and cycling link on the bridge that should have been there 60 years ago. It’s popularity will probably do more for convincing people of the benefit of cycling infrastructure than anything else could.

        3. That’s true, Jezza. Indeed I’d go further and say the main issue with cycle lanes on arterial routes isn’t money, it’s AT’s systemic bias in listening to the minority resistance to road space being reallocated.

  2. It was a brutal commute on the North Western on Friday night, probably going to be worse today. It’s all well and good telling the Shore to use the NW Ring Route as an alernative, but it’s recently returned to gridlocked form even just with traffic flows to the North West. I guess we’ll be waiting for resilience improvements out our way now for even longer, having already waited three years while nothing happened with Light Rail.

  3. The main behaviour change should be towards working from home as a permanent mode shift.
    Just as with health and safety: the first option is to design the entire risk away.

  4. So a new road crossing wouldn’t be able to help this situation unless there were huge interchanges at each side, as traffic can’t switch between routes when there’s a problem. Ignoring environmental and local traffic impacts I guess one is possible obliterating the whole Akoranga area, but in the city? Where? Wynyard Pt/Victoria Park?

    yeah, that’s gonna happen.

    Anyway where does all the extra traffic go? The city is going to have even less, the CMJ is entirely full, I guess they could keep tunnelling to…? South of Mt Wellington? The Bombays?

    Just get on with the light rail/metro crossing already. And price light passenger vehicles on the clogged motorways properly.

    1. It’s worse – the new road connection would require space all the way up to Constellation. It’s time for a region-wide roll-out of Light Rail. North, East, South and North West. Once we have the North South and motorway splines, start adding crosstown routes that serve town centres and unshackling density. We all know this is going to be what has to happen eventually, so why are we still wasting time on the same old debates?

        1. A second road crossing sounds like destroying the village to save it. The shore obviously needs a stand alone metro/light rail crossing.

    2. The general public see the harbor bridge as the main bottleneck in the citys car transport. Which is simply not true, and a small amount of thought reveals this.

  5. So all the wasted words and energy on light rail to the airport when all along we needed light rail to the shore or perhaps more ferries then light rail if you haven’t got time or money for another bridge or a tunnel.

    1. The reason dominion road was prioritized for light rail first is because it will reach max bus capacity much earlier than the northern busway right? AT are projecting that despite this and the ongoing rail replacement bus program they will still have plenty of capacity. It seems completely reasonable to me to continue with the current plan of dominion road light rail.

      1. CBD bus capacity was the bigger issue than Dominion Rd bus capacity. This could be solved by using rail for any or all of the existing Northern busway, the proposed NW rapid transit or Dominion Rd.

        1. According to the business case from about 2016 or so, the driver for the Dominion Road light rail was bus delays inbound on Symonds St / Wellesley St. A northern LRT wouldn’t do anything about that, but it would head off similar problems happening on the northern approaches eventually.

      2. Finding a legacy project for a very aggressive and polarising CEO of AT was the reason Light Rail on Dominion Rd was prioritised. There is a already a road widening designation on Dominion Rd for passenger transport so they figured it would be the easiest. Then they shoe-horned the design so they didn’t even need that (or at least so they thought.)

      3. Any kind of rail across the harbour needs a network on both shores to connect with. LR on Isthmus and NW was never instead of across the harbour but in preparation for it.

        Arguably NW is more urgent as it has nothing, at least Isthmus buses can’t be prioritised and squeezed further, even if that’s tough on the city centre. NW to NS through city could be accelerated.

        Either way whole network has to be planned and mode, or modes, be committed to.

        1. Agreed Chris. Accessible cities evolve from deciding what the best long term outcome is then working backwards to see how you implement that, rather than incrementally projecting current trends forward and catering for another ten years of demand. In the long term LRT from Albany to the airport serves a lot of people, and takes a lot of pressure off the CBD. This incident does to change that. Incidentally you could have built the whole LRT from Albany to the Airport for the reported cost of the harbour road tunnel.

        2. Yes “Accessible cities evolve from deciding what the best long term outcome is then working backwards to see how you implement that, rather than incrementally projecting current trends forward and catering for another ten years of demand.”
          And and probably some of these lines LRT from the start or fairly easily upgradable to LRT. Very long term any LRT lines or sections can be replaced by higher capacity metro or heavy rail systems if needed. This would suit the more grade separated areas, thinking north shore lines from the city centre would be better for that. eg tunnel from Aotea Station to a main northern centre of LRT station say.

        3. People always talk about upgrading lines when they are full, but why. Why not build another when it is needed instead of shutting down the first one exactly when its working at its maximum effectiveness?

  6. We must be a very rich country if we can afford to spend $6 billion on providing an alternative to a 2 week long 2 lane closure every 60 years…

  7. AT should be adding bus lanes to the Bridge from the Auckland CBD area. From the North Shore the Buses can force their way onto the Bridge as the bus lanes finished just before approaching the Bridge. A good run in, but a slow road home.

    The picture of 4 lanes now being used reminds me of the 1959 ones when the Bridge first opened, except they using the 1969 Clip Ons.

  8. Given the state of traffic modelling in the country, there’s been a need to test it against taking big steps to change allocation of space. This is an opportunity WK would be irresponsible to pass by: They should see how much modeshift is achievable using tactical solutions to increase people flow over the bridge.

    Put in the bus lanes on the approaches that are needed. Make bus lanes on the bridge. Price peak hour driving using whatever technology can be set up quickly. AT should quickly put in more cycle parking and cycle lanes to all the bus stations and price parking.

    And monitor it all closely. Then when the bridge is fixed, don’t return all those lanes to traffic. Use one of them as cycling / walking lane too.

  9. It will take a few days at least for regular car commuters to make alternative arrangements and new temporary normal to establish. Resilience for a city is being able to do business even when something breaks.
    At least Waterview tunnel and Upper Harbour motorway are doing their bit, even with NCI unfinished. Would the NW busway have been a good idea when Waterview and NW widening were happening?
    Bus priority lanes from Onewa Road and Fanshawe Street as close to the bridge split as possible are the obvious must have, while there is plenty of spare space on the approaches.
    Much harder is extending bus priority on the regional roads approaching the motorways. Also, can bus priority lanes on NW be created for this incident?

    1. Yes, building a proper busway when SH16 was being widened would have been a smart move, alas certain politicians didn’t believe it’s necessary.
      Current bus lanes on SH16 are very intermittent and don’t continue through the off/on ramps, which in total gridlock means that the buses can’t get through either. In order to fix that AT has a project in its pipeline, but that might be years away.

  10. Good post Matt. A second road crossing would be dumb as f**k.

    So National have said, “National will get started quickly on the work to build a second harbour crossing in our first term in government. Our aim is for work to start in 2028 with a road and rail tunnel under the Waitemata Harbour. We will also fast-track the consenting work required. This will be New Zealand’s biggest ever infrastructure project, and will require a huge amount of work – but it will be worth it.”

    Why are they so determined to really ruin our city?

    1. Sometimes I really wish central government left Auckland alone. Light rail was all planned out, AT knew exactly what they wanted. It just needed to be funded. In swoops the government to save the day and look good / take credit for the project and boom, total political disaster.

      1. The reality is, central government is one that going to stump up with the cash , as Auckland Council doesn’t have the money do it alone.

        This is why we need to have a national public transport agency separate from NZTA to plan, finance and procure bus, light rail, urban/regional and inter-regional passenger rail and ferry services across all 16 regions.

        1. But who is going to pay for this damage NZTA , Central Government or the trucking companies insurer ? , if so the insurer they will b fighting in court as it’s going to cost them to much . And also if it’s the insurer it could end up like the Canterbury earthquake repairs all done will dodgy contractors and done on the cheap .

        2. AT had a credible plan for light rail that has been scuppered by a government agency. On what planet would creating another government agency improve this situation.

        3. I know that central government would have to fund it mostly. But that doesn’t mean that they have to take the project out of Auckland’s hands right? Like AMETI for example I believe.

        4. Jezza, it seems much more like Phil Twyford’s personal incompetence was what totalled LRT on Dominion Rd. Sure, maybe if the government had just fronted the cash to AT, it would’ve been done by now so, in that sense, the slow movement when the project was initially transferred was the problem… but I have to ask, why was there slow movement?

          Given everything we know about Phil Twyford, it would make sense that he was a LRT sceptic that was forced to implement what was a headline election promise… unless it could somehow be delayed long enough that something else would happen and they could move along.

          That being said… another agency doesn’t seem like a good solution to me. A funding board that approves or lays over local transport body plans? Maybe.

    2. “National will get started quickly on the work to build a second harbour crossing in our first term in government. Our aim is for work to start in 2028 with a road and rail tunnel under the Waitemata Harbour”

      John Key said much the same in 2013 , except the work was going to FINISH in around 2028.
      They didnt do a thing of course for the following 5 years , there was no money and the idea didnt stack up . Same goes for the Bishop- Collins under harbour promise.

  11. Under the heading of “It’s an I’ll wind that blows nobody good….”
    Reflect on the grumbles that the original harbour bridge was too small and the ‘clip on’ doubling. If an eight-lane single structure had been built in the first place, today would be ferries only.
    The clip-ons are actually providing exactly the resilience that is needed, although a separate PT crossing would add a lot to that.

    1. Actually the plan was for a six lane single structure, before it was reduced to five, then four in order to be actually funded.

  12. Also, there is the sentiment about how we should not spend 300 million on something that is used by only 2000 people per day.

    I can see the same argument about any extra crossing. Some untold number of billions for just 30,000 people per day.

    1. Yes. Mind you, it seems like we’re having opportunities for value-for-money being thrown at us, and we’re just ignoring them.

      It’s heaps cheaper to get people across the harbour on buses than in cars. It’s heaps cheaper to provide cycling and walking across the harbour on reallocated lanes than having to build new structures. Together, these concepts are complementary. Reallocate space from cars to buses, and it makes space for cycling and walking.

      Covid’s shakeup of the economy should’ve taught us to use this value-for-money solution.

      This “climate gust” as we could call it, is yet another chance – the reduced traffic capacity is staring us in the face; just need to complete it with bus priority and then with retaining some of the space for walking and cycling when the repair is done.

  13. Although the damage to the harbour bridge is unique (first time in 61 years), and will take time to sort out, this is not the first time we have had bridge traffic disrupted for 5 hours plus. Roughly 40 years ago on a weekday afternoon a truck rolled on the southern approaches to the bridge, effectively blocking all northbound traffic except those using the Curran Street on ramp. Cell phones did not then exist so communicating options to drivers was limited to a car radios – most of us had no idea what was going on and assumed that it was a local accident that would soon be cleared. The net result was grid lock throughout much of the city as long queue of cars headed for the bridge that was effectively closed for north bound traffic blocked all other traffic in interesting streets. Most people figured that the blocked lanes would surely be cleared “soon” and grimly hung in for hours of frustration. I was stuck on Grafton Road with no intention of using the motorway system, let alone the harbour bridge, and like most other drivers completely mystified about what was happening and when it might be resolved. This single event was a key driver of what eventually became the Western Ring Route strategy – a flawed approach since it is based on drivers from South Auckland heading for the Shore knowing in good time that SH1 is blocked and they need to detour via the WRR. It is of limited value for those on the isthmus since traversing clogged roads westwards to gain access to the WRR could take half an hour or more and yet most road blockages get cleared in that same time frame – so for most drivers the sensible response is to “grin and bear it” (hang in there) rather than attempt to drive around a very long detour that may actually take longer. Lawyers say “hard cases make bad law” – i.e. just as we should not base our legal system on addressing a handful of exceptional cases, similarly we should not base a key part of our transport system on freak events.

  14. What got me NZTA on the news said that engineers are working on the repairs to the structural member , and the shots they showed on the news they all seemed to be playing with their calculators . Why don’t they find the Original Drawings which has the size and length , and find someone with an imperial tape measure and build a new one , and looking at the member the only extra person they will need is someone that can do the hot riveting to fix it together . And if they can’t that person/s import him from overseas .

    1. Maybe the current strut is a good indication of the size. For some reason it will take 5 weeks to make a copy and hang it up there.

      1. well seeing as we no longer have that capacity to make steel members of that size, I’m guessing that they will need to have the steel imported – probably from Asia – and sent on a boat. So 5 weeks is fair.

        And be prepared for when they do install it – they’ll have to close many lanes, have at least two giant cranes, and possibly all sort of temporary proposal / cables as well. Get the cameras out – it’ll be an occasion to remember!

        1. “we no longer have that capacity to make steel members of that size”

          Nonsense. It’s a simple plate and angle fabrication and I can think of many workshops in the Auckland area that could produce it. Plate is NZ-made and while angle is imported (and as far as I am aware always has been) there is plenty of stock. In my experience something such as that could be produced in less than 2 weeks (including galvanising) if sufficient monetary incentives were provided.

          What is going to take time is devising the hydraulic tensioning rig and getting it built, working out a rigging/lifting methodology and ensuring that measures are in place to do the job safely.

          …and no, it won’t require giant cranes. Giant cranes are very heavy and that is not what is wanted while replacing a structural element that is partially supporting that crane. The strut won’t be particularly heavy and the radius will be modest. I thing I would be looking at something like hydraulic winches attached to the existing structure lifted into place with a relatively small and light crane. All this sort of planning, designing and manufacturing of temporary steelwork etc takes time.

        2. And going by what NZTA said on the news the new Strut weighs around 4.5T so a block and tackles should be able to lift it into place .

    2. They are trying to see if they bolt a new temporary plate up there where the damaged section is, if the bridge can safely take the load. Those uprights are under a lot of tension and anything temporary wont be pulled to carry the designed loads.

    3. Have you considered that the structural member was under tension so the bridge has likely dropped a bit so will need to be raised to attach new member. Either way not as simple as you make out

    4. While this isn’t my field of engineering, trust me… It’s never as simple as an armchair expert would expect.

      You’re also assuming that the original drawings are still available and that the structure wasn’t massaged during construction (design vs as-built vs creep over time). Another issue is what composition was the original steel and will new steel of the same composition have the same strength? What about grain uniformity? It’s entirely possible that the engineers will discover aspects of practical bridge engineering that the original engineers didn’t envision, resulting in even more steel needing to be replaced…

      1. Yes it is far more complex. It will take one week to fabricate, finish and hang up there and at least four weeks to do a structural analysis to make sure something that has existed happily for 60 years is up to the task, then there are peer reviews, safety plans, peer reviews of safety plans, risk assessments and quality assurance processes and a few other government department style of things designed to make sure nobody has to take any responsibility.

      2. Agree. There are always those who in their ignorance think that a task will be simple and straightforward, even if it isn’t at all. Whenever I read “surely they could just . . . “, I cringe.

        1. +1 Although they are doing good, it would be much better if NZTA provided more information. It’d help with stuff like this. Plus if they doing a shit job they could get called out on it. There should never really be a reason that a government agency tries to keep plans under wraps.

      3. One complication is that the damaged piece was a tension strut – so it was getting stretched while it was in place. Now that it is not in tension anymore the rest of the bridge around that piece will have shifted slightly to compensate. So, there will be some design work working out how to jack the rest of the bridge to get the replacement strut back into tension and the rest of the bridge back to normal once they put the new strut back.

        1. Yes it is called making the strut the same length as the last one. Then they attach it at the top and pull until it reaches the bolt holes.

        2. I think it’s a bit more complex than that. It’s the deck that needs jacking up to meet the strut. Random “pulling” will make things worse.

        3. I thought struts by definition, are in compression.
          Tension members are ties.

          Is it a strut or a tie?
          Do they have to push it or pull it into position?

        4. The media and maybe NZTA have been calling it a strut so I’ve just copied that.

          I am not sure how they will jack the bridge and am curious to find out. It sounds like they have to spend some time working out where and how much to jack it so that they can put the replacement member back in tension and redistribute the loads through the surrounding members to get the bridge behaving like normal.

        5. I am genuinely not sure.
          If the deck was suspended from the arch it would be under tension.
          But as a composite structure the members between the deck and the arch could be in compression maintaining the seperation.
          I knew only enough civil engineering to know when it was needed, and I did not know it, so time to get somebody who did.

        6. It is too slender to be in compression. Compare it to the vertical beside it in the video. I promise the structural engineers will make this as complex as they possibly can and end up putting back something almost identical to what is there. The tensioning will be nothing more complex than pulling the two ends together so the bolts can be put back. I would expect the only change will be when they tell the fabricator to use 3/4 inch and the fabricator will say we only have 18mm or 20mm these days- which do you want?

  15. Crazy idea time, but desperate times call for desperate measures. Im sure the centre section could take load from bicycles rather than cars. Use traffic management to cross the (stopped) traffic southbound at Sulphur beach, then cycle across (on lane furthest from damage) then cross again on the crawling northbound traffic and down the service entry to the water front. Im sure you would get a fair few people who decide a bike ride is better than sitting in traffic. And if it the traffic starts to move too much then jump on the ferry to Birkenhead/Devonport with the bike!

  16. Why the fixation on the 2nd crossing for PT? I don’t disagree that its needed at some point but wouldn’t Light Rail or Rapid Bus from Rosedale to Hobson then West Gate, Te Atatu then City provide the rapid redundancy we need and bring cars off both motorways and be a lot quicker and easier to implement short term? Its already part of the Congestion Free Network, just needs prioritising differently.

    1. very few people are going to use that day to day. Which is required for a system to be built in the first place. 33km around by westgate vs 16ish through the harbor. it doesnt make any sense for the main north south route go that way for light rail, which is what I think you mean. I dont even think it’d be cheaper. Tunnels while expensive, are not crazy crazy expensive. Its the stations that get ya.

      1. I think what you mean to say is “Very few people are going to use that [for an end to end journey] day to day.”

        A Western ring rapid transit route (whatever mode so long as it has its own right of way and priority at intersections) would be hugely useful for the people that live out West. It would be heavily used every day by people making intermediate trips, just not many end to end ones. Once every 60 years when a freak accident reduces the Harbour Bridge’s capacity for a few weeks then such a rapid transit route would be able to take some of the load.

        You’re right that this wouldn’t necessarily be cheaper than a rapid transit tunnel under the harbour. However, by connecting up a bunch of high growth areas poorly served by public transport, it would actually be a more useful addition to Auckland’s PT network. No doubt eventually the Northern Busway will eventually need upgrading to light rail / light metro but extending rapid transit to currently unserved areas of the city should be a higher priority.

        1. Not such a bad idea, as the RTN link from Constellation to Westgate is on the agenda anyway. The investment problem with having many major projects to deliver is what sequence of investment will make most sense. We need to avoid political pork-barrel glamour and stick with a ‘best’ plan. Of course, choice of how much to spend on any one project does complicate this. But we should only change plans when something like available technology really changes options.

        2. Fair, I read light rail on Joe’s original comment. And glossed over the rapid bus part. I think the current GA RTN is the best approach. But I would seriously doubt that it would make sense in the near future for that upper harbor route to be light rail. Agree with everything else though.

  17. The bridge needs travel demand management long before any additional road crossing. This would also assist with the current situation.
    The bridge and city side approaching motorways are currently free flowing with light traffic.

    1. Yes, and since the TDM for the bridge is so clearly about reduced vkt, it’s a great project to explore what the sector should be doing everywhere in the various road network optimisation programmes.

  18. At Friday, Northshore bus such as NEX got cancelled until very late.

    Passengers ends up get stuck in city without any way to get back home. There is no way to walk home. Those people where so frustrated.

    If you have a car you can at least know you will eventually get home after few hours. But people without a car and without any public transport, and a non walkable bridge, means they can’t get home at all.

    It is another very bad example of how AT handled public transport. On one hand they want people to use public transport, but on other hand they treat people using public transport as second citizen.

    It makes passengers lost the faith to public transport.

  19. Given there was a hefty gust going through which flipped the truck its not only the trucks momentum which damaged the bridge but also wind force on the bridge structure itself.

  20. The NZTA have just announced they’ll have a temporary bus lane in place northbound though St Mary’s Bay from Fanshawe St to the base of the Bridge in time for the evening peak.
    They’re also closing the Curran St on-ramp until the bridge is “fully operational”.

        1. Yes agree all day would be better. Seems this afternoon closure caught a lot by surprise and are caught in the diversion clogged up traffic. Wonder if there were electronic signs warning motorist further back on main routes? Google doesn’t yet show it as closed so wouldn’t help.

  21. Regarding hot rivetting, the technology is still alive and well, thanks in some measure to the navy dockyards, our transport museums and heritage railways, where the skills and machinery involved have been passed down to the younger generation. No need to look overseas.

  22. Reading the article it seems that the author swings the argument any which way to suit the outcome desired.

    One the one hand it says ” Any new crossing will result in one of two things.
    1. ….
    2. No increase in capacity. It’s also been suggested that in the event of a new crossing being built, the existing bridge could have space on it repurposed, such as for bus lanes and maybe even bike/pedestrian lanes etc. This would mean there is no real new capacity across the harbour and that the level of demand stays about the same. But that also means we’re still having to accommodate that traffic in fewer lanes than we do now.”

    And then further on it says “There are other forms of resiliency

    The best way to add resiliency to crossing the harbour is to have a multiple separate networks, ones that is not affected by whatever happens on the others. Separate networks in the form of Skypath and a dedicated public transport crossing.”

    So, in one paragraph you argue that adding bus lanes and bike/pedestrian lanes adds no increased capacity. And yet further on you argue that that is exactly what is required for resiliency

    This simple man is confused. Capacity? Resiliency? Aren’t they pretty much the same in this context?

    1. The author is talking about road crossings in that section / capacity of the roads. Adding capacity / a new crossing in other modes would however increase resiliency. It could be made slightly clearer what mode the author is talking about in that section, but if you read the lines above, he says:
      “Resiliency is often cited as the main argument for building another road crossing but even if we already had it, it wouldn’t have prevented chaos. Here’s why:”
      There is an image between the next bit which is why its a little confusing.

      1. So to summarize:
        increasing road capacity with a road tunnel crossing, will not increase the resiliency of the cities transport network. (plus the second road crossing wont really increase the road capacity in a very meaningful way.)
        Increasing capacity / effectiveness of other modes will increase the resiliency of the cities transport network. (which would probably include a rail tunnel harbor crossing)

    2. All made sense to me. You’re right there is a simple man/woman that is confused but you might find you’re looking at a mirror.

      1. Taking your advice I have looked in the mirror, and yes, I can confirm that I am a simple man.
        Perhaps you could explain to this simple man how building a new crossing, and then repurposing the existing bridge doesn’t give any extra capacity, whereas clipping a skypath onto the existing one does.

        1. Lots of reasons you wouldn’t want, say, another general traffic (cars, trucks etc) bridge or tunnel then using the existing harbour bridge for say buses and walking, cycling etc. Good question though:

          I think the main one would be you would spend a lot of money to put a new 6-8 lane general traffic bridge and particularly more for a tunnel across. A tunnel costs a lot more to operate with ventilation & safety systems etc etc. Bridge or tunnel would have environmental issues to contend with.

          A dedicated public transport (probably light rail) bridge or tunnel is far smaller costing a lot less to plan, construct & operate. The “Skypath” is pretty cheap in the scheme of things really & can be done in the very near future. Another whole crossing would take years of planning, consents etc.

          What we don’t want is additional general traffic lanes as there is no real capacity to handle it at each end including the city centre. With induced demand, these lanes would all fill up just as the author alluded to with the Western Ring Route (and this is a once in a 60 year issue, so can’t justify yet another backup bridge etc for another similar event.)

          Some on the blog have argued to re purpose the existing Harbour Bridge would be the cheapest, fastest solution. Probably only political problems with that one.

        2. I’m using southbound as an example but I presume northbound will be similar. By turning the harbour bridge into a centre city off ramp we remove about 25% of the traffic, currently about 75% continues on to other destinations through the southern and western motorways, and this is a dropping statistic year on year with more people taking the bus to downtown. So win one we get about a lane of extra capacity for through traffic. Without significant widening efforts though out the rest of the motorway system around in spaghetti junction and all the way north on the shore, we cant really do any better than that.
          Now for what happens to the bridge. Left at about 25% needed capacity, we can take a couple lanes for bus / rail and another for walking and cycling. But really kind of makes the bridge pretty redundant. Especially with dropping need.
          So we replace the bridge with at least 4, perhaps 5 lane wide tunnels (which is absolutely massive) for huge expense and dont really get that much extra capacity. Now the capacity we free up for through traffic will pretty much immediately fill up. One more lane ain’t that much. So congestion wont really improve, there would be more trips made however, which is really the end goal. I really just dont think it would be worth the price tag. We would kind of be replacing the bridge rather than really augmenting it. Plus there’s the ongoing costs issue, tunnels are vastly more expensive to operate than open air motorways.
          Even NZTA, an incredibly pro car organisation, doesn’t think its a good idea. https://www.greaterauckland.org.nz/2019/03/06/nzta-confirm-harbour-crossing-road-project-is-a-waste-of-money/

        3. Graham – it’s reasonably obvious reading the lead in section to the quote you selected above that Matt is talking about vehicle capacity.

          It is true that building a new road tunnel and repurposing the existing bridge would add overall capacity, however this approach makes little sense. It would be considerably cheaper to build rail tunnels instead and put a $300m pedestrian crossing on the existing bridge.

  23. Engineers of the bridge repair are talking about large jacks and having to pull parts of the bridge apart to take tension out of replacement part to install it. Why don’t they just use a replacement part with a built in fence strainer (a large one), works every time everywhere else in NZ 🙂

  24. Amazing. The first resource I thought about was transport blog upon hearing this news. Good analysis and right as always. Good luck Aucklanders, I left many moons ago, never looked back!

  25. So the thing is, if the recommend option for the new harbour crossing existed this would have never have happened and people would be enjoying better PT and better trips on the road. This is because the central span was to be converted to one lane each way for PT and freight only.

  26. I’m using southbound as an example but I presume northbound will be similar. By turning the harbour bridge into a centre city off ramp we remove about 25% of the traffic, currently about 75% continues on to other destinations through the southern and western motorways, and this is a dropping statistic year on year with more people taking the bus to downtown. So win one we get about a lane of extra capacity for through traffic. Without significant widening efforts though out the rest of the motorway system around in spaghetti junction and all the way north on the shore, we cant really do any better than that.
    Now for what happens to the bridge. Left at about 25% needed capacity, we can take a couple lanes for bus / rail and another for walking and cycling. But really kind of makes the bridge pretty redundant. Especially with dropping need.
    So we replace the bridge with at least 4, perhaps 5 lane wide tunnels (which is absolutely massive) for huge expense and dont really get that much extra capacity. Now the capacity we free up for through traffic will pretty much immediately fill up. One more lane ain’t that much. So congestion wont really improve, there would be more trips made however, which is really the end goal. I really just dont think it would be worth the price tag. We would kind of be replacing the bridge rather than really augmenting it. Plus there’s the ongoing costs issue, tunnels are vastly more expensive to operate than open air motorways.
    Even NZTA, an incredibly pro car organisation, doesn’t think its a good idea. https://www.greaterauckland.org.nz/2019/03/06/nzta-confirm-harbour-crossing-road-project-is-a-waste-of-money/
    It’s not really stated how much it would cost, but really there would be far better places to spend money on for transport in Auckland. If the goal is to reduce congestion, then it wont do that. But if the goal is the add another third of cars as through traffic mainly then sure, it would probably do that.

  27. And this from AT with the numbers up on the Ferries yesterday , and at least the weather was perfect ;-

    ” Auckland, you’re doing a great job. Thanks to people using their public transport options, ferry services yesterday saw a jump in patronage, compared to Monday last week. Here’s the results of ferry services in the Waitematā Harbour:

    • Bayswater – 121.5%
    • Birkenhead – 283.6%,
    • Devonport -105.9%
    • Downtown – 92.6%
    • Hobsonville – 38.2%

    North Shore bus services saw an increase of about 5%. On both ferries and buses, there is still plenty of capacity for travel to/from the North Shore. Using public transport if you can, means that those who do need to travel by car will have a smoother journey.”

    1. Oh almost like going back in time with the email today with the 9pm closure overnight for southbound harbour bridge lanes:
      During the closure, there will be no north or southbound bus services over the bridge. If you are leaving the city after 9pm tonight, you will not be able to use normal bus services, due to buses not being able to return to the city. Instead you need to use the Birkenhead Ferry, departing from the Downtown Ferry Terminal at Pier 1.

      At Birkenhead, buses will meet the ferry and transfer you to Akoranga Station. From Akoranga Station you can catch your normal bus service home.

      Good they had just repaired/upgraded the Birkenhead Ferry terminal.

      1. And I wonder how many of those new passengers will still us the ferries after the repairs are done ? , or if the weather changes , as right now they are fair weather sailors .

  28. How vulnerable are high-sided double-deck buses to being blown over on the bridge? If this had happened to a bus we could have had a real tragedy on our hands.

  29. Please no more rhetoric and carefully crafted arguments. It is time to build another crossing, whether we go over or under. It is the 21st century and we live in a Super City and our population is growing. I am more than happy to get the paperwork started. Where do you want me to sign?

    1. I think most people agree with this. The argument is whether it should be yet another road crossing, or whether it should be for rail. The absence of a rail service to the North Shore is in large part the reason for the insufferable traffic conditions pertaining.

    2. Wayne, it seems you assume we need more crossings because the population is increasing, but we can put our infrastructure to better use. By looking at the range of roading per capita that cities have, we know that lower roading km per capita mean lower emissions and lower maintenance costs per capita.

      Basically, the transport system we’ve built over the last 60 years isn’t serving anyone particularly well.

      Looking at reutilising all this expensive roading infrastructure more efficiently, retrofitting it for a new transport system that’s cheaper to run and maintain, is not ‘rhetoric’ or ‘carefully crafted arguments’.

      In fact, it’s the only responsible thing to do.

      We don’t need a new crossing, just as Auckland could have gone up not out instead of building the bridge in the first place. But building a new crossing may be a good option. What needs to be done is a proper look at what our options are. As far as I can tell, no-one has done a proper assessment of starting from scratch, looking at what a complete repurpose of the entire harbour bridge approach areas could provide – for radical modeshift, emissions reductions, and liveability. If totally unrestrained by the expected kickback by traffic engineers, the possibilities could be quite appealing to the public.

  30. I am always a bit concerned riding on the edge lane in the double decker Northern Express when windy or if there was a crash causing the bus to be hit or go off the edge. Has it even been considered if it is safe for the bus to be on the edge lane. Anything is possible this year

  31. Bruce many years ago large vehicles were excluded from using the Clipons when they were doing the strenghtening , so why don’t the do it again after they have finished this set of repairs or just ban them from using the outside lanes fullstop .

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