In 2010 Len Brown campaigned on three major rail projects, the CRL, rail to the Airport and rail to the Shore. If there was one issue with them though, it is that to some they are too bold. Despite getting strong support among many members of the public, vocal opponents point to primarily to their price tags as a reason not to build them. However when it comes to the second and third of the projects I mentioned above, I also wonder how much of the opposition to them comes from the mental block of getting over or under the harbours. If we had a rail line to Mangere Bridge or to Akoranga, how different would the argument for extension of the network be?

History and common sense has shown us that when it comes to building expensive infrastructure, it is best to break it down into smaller more manageable projects. There are a couple of prime examples. Earlier attempts at building the CRL also included double tracking and electrification. They fell over in a large part due to the massive cost of doing it all at once. More successfully we have seen the tactic employed across the motorway network where the system has been expanded one project at a time. With the Western Ring Route for example, lots of smaller projects have been much more palatable to the general public yet by the time it is completed, the cost could reach $4 billion. Had the NZTA or its predecessor attempted to build the whole thing at once there would likely have been a lot more opposition.

I guess what I am getting at is that we need to find ways to break down projects and reduce costs wherever possible. In the case of the two rail projects mentioned at the start, getting rail across each of the harbours would likely change these projects from looking massive and expensive, to ones that we could break down over a period of time, extending the network one station at a time. At this stage the thinking about rail to the shore seems to be focused on integrated it into the same tunnels as a road crossing. For rail to the airport you may remember hearing that the recently completed duplicate Manukau Harbour crossing was future proofed for rail. But was it really?

Well it kind of was, but it turns out not in a way that seems to be that useful.

The story goes something like this. Transit, the predecessor to the NZTA, wanted to build the duplicated harbour crossing. They, acting with their motorway only blinkers on,  came with with designs and proceeded to try and get consent for the project. It was then that the Campaign for Better Transport and others became aware of just how mono modal the project was and challenged Transit to include provision for rail the the airport, something that had been on high level plans for some time. It took the threat of legal action for the agency to concede and start investigating how they could be done.

I have now been provided with documents from the time (7MB) which discuss the level of future proofing that was included in the project. It started with a high level investigation into what the potential route options were. They consisted of two routes on a separate bridge to the east of the motorway, one through the middle of the bridge piers, sharing some of them, and one to the west of the motorways. That was then narrowed down to two routes, the route through the middle piers (B) and the route to the west (C) as shown below.

So far so good and option B is what has been promoted to the public. However in my opinion, here is where things start to go wrong.  Engineers found that because the bridge hadn’t originally been designed with rail in mind, that for option B, there simply wasn’t enough space to include a double tracked line. By this time the bridge had now been consented and the construction contract awarded. Changing the design enough to allow for a double track line was considered too costly. However it wasn’t only financial costs, but the need to get consents changed and that it would have caused delays to the construction.

MHX options 2

That means the only option available if we are to use the newly built bridge is a single track line as shown above. You may notice it is called option B3. The reason for that is based on the engineering standards, the original route option was not only a single track but due to the curves it and issues should a collision occur, it would have seen trains limited to 25kph. By strengthening some of the piers and a few other changes, engineers were able to improve the option enough to allow the design speed to be improved to 70kph.

As the line not only serves the Airport, but also the commercial areas surrounding it and the residential areas of Mangere and Mangere Bridge, I suspect that we will eventually need to be running frequencies of at least 6 trains per hour in each direction. I simply can’t see a single track section being sufficient to handle that kind of service level without causing potential delays. That means that despite all of the talk of the new bridge being future proofed for rail, the only realistic option appears to build a double track crossing on a brand new bridge. Unfortunately there doesn’t seem to be any estimates as to what the cost differences between the two options are but I would have to imagine that double track option would be much more expensive.

More than anything, I think what this case highlights is the result we get when we plan infrastructure in isolation. Transits role was to build roads, yet if they taken a little bit of time to think about what the city might need in the future, they could have made changes to the bridge design early on that could have avoided this problem. Instead, as a result it appears that to fulfil the vision of getting rail to the airport, we will have to stump up for another bridge across the harbour. It also means that we are going to have to be extra vigilant when agencies describe a project as future proofed. It appears that what the engineers and planners call future proofed, isn’t necessarily what us, the general public would expect.

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  1. Question: Will we be seeing a post about the fringe benefit tax on parking soon?

    Regarding the single track while it certainly is annoying, we have to move on. Also I’m pretty sure that 6tph is perfectly doable. The single track is only going to be for a kilometre or so (AFAIK).

    1. “We have to move on”? From a decision made 3 years ago? That may cost us an extra $100 million in the near future?

      I don’t think so Frank – the implications of this poor decision need to be brought to light and used in courtrooms and engineering classrooms around the country to show how autombile-centric planning continues to this very day. Hell, most of the people involved in this decision probably still work at NZTA and/or in the private sector.

      We have to acknowledge past mistakes honestly if you are ever to learn from them – and to this day I have not seen anyone from NZTA stand up and apologise for this bridge. What a shocker.

      P.s. 6tph is only a train every 20 minutes in each direction, i.e. 1,500 pph. I don’t think the Airport Rail Line would stack up at that level of frequency.

      1. Hi Stu, I am interested in writing a post about the 881 bus service is there a particular format you guys prefer, and how do I get it to you?

    2. It was 6tph “in each direction“, or one train every five minutes. That would be pushing the safety envelope right to the edge of breaking, and a single track across the harbour also provides no way of switching other trains around a breakdown that occurs on the single-track section.

  2. Stu – Matt L talks about 6 tph in each direction – that is a train every 5 minutes overall across the bridge…

      1. As a part of the RTN it would have a minimum of 6thp each way most of the day all week to begin with. Higher frequencies would be a response to demand. Note that every RTN improvement [rail + busway] with the notable exception of the Manukau City spur [so far] has exceeded projections for ridership.

  3. Because Transit is like the beggar outside the State Highway builders’ banquet what little we do get to build is half-pie and almost immediately redundant and then needing to be expensively and inefficiently rebuilt. – The Britomart Throat, the single track through Onehunga, Kingsland Station, the terrible squeeze at Newmarket is going to cause trouble soon enough too. The fact that the Busway is only a Busway for 41% of it route does hold it back…. and so on. So if we build a single track across here because the car crazies refuse to accept there will be any demand and it’ll be a cheaper for now we will find ourselves fighting for a second structure for the other track soon enough. Or we could build it properly once.

    I know the argument, Matt uses it above, and I am glad for the actual 41% Busway over a 100% but unbuilt one, am glad for the single track Onehunga Line that is actually there and working, but I do think we’ve done enough proof-of-concept trails now it is time to invest where the growth and demand is, and has been shown to be all this century, and spend our not inconsiderable transport investment money more wisely.

    1. Yes and clever staging of delivery should not be an excuse to cut ridiculous corners. In this case, ARTA wasted $2.5 million on a “solution” that is useless.

  4. What. A. Shocker.

    Single track? What planet do these people live in? Or what century?

    Amazing that basic accountabilities of the relevant Government agency are so woefully delivered that “we are going to have to be extra vigilant”.

  5. It’s always been rather clear that the bridge would not be able to carry heavy rail over it. I used to always wonder what you guys meant about it being future proofed as the only options I could see we’re either a visually intrusive bridge or a tunnel.

    I note the existing bridge is visually intrusive but a new rail one taking a path of its own would make it look like a real mess.

    1. regarding what’s built, “in theory” there is scope for a single track rail bridge resting on the horizontals of the ‘A’ frame bridge supports, but such a bridge would be very close to sea level and would probably have salt corrosion issues. I am not sure if there would be room for catenery.
      In this case, the wider issue would be that unless there is an overarching strategy / plan for the airport line determining its true purpose, and hence identifying its broad route through Mangere, you won’t know which side fo the motorway you want the railway to end up on at the south end of the bridge. Without knowing whether the railway is crossing the motorway or staying to one side of it it is going to be pretty difficult to ‘future proof’ the road crossing. If you stand on the south shore you can see that there was a real opportunity to line up the new bridge piers with the old to get a good clear route through the bridge – if only you knew at that planning stage what route was actually needed for the railway.

      Without a long term vision (at least 30 years out) of the desirable future look of the railway network then there is always going to be a lack of future proofing – or inappropriate future proofing.

      For another example of this false “future proffing”, you need look no further than the “Third Main”. Everyone talks about the ‘Third Main’ as the savious for capacity issues south of Otahuhu. That is an incredibly short sighted vision giving a false sense of security. The vision should be for a four track railway – even if we only need three tracks in the immediate future. But I can just see all the bridges being rebuilt to accommodate a third track, and then not many years further along, (and in my view, “not many” is a really small number) further traffic growth being constrained because it is too expensive to rebuild the bridges all over again for the fourth track.

      1. Richard the line heads west side of SH20, like all things rail in Ak plenty of planning is all there if you look.

        And indeed the 3rd main is so visionless, oh and see what they are doing right now at Panmure a double stacked highway on the rail designation that renders the necessary tracks hugely expensive. Anti-future proofing. Like Newmarket. There were four tracks through there.

        Of course Kiwi Rail are a huge part of the problem they are clearly being run by people tasked with dismantling the existing network in order to try to prevent its revival.

        1. It’s not the looking that is the problem. It’s the finding. I didn’t see anything definitive about which side of Route 20 the line was going.

          Just looking at Google, it seems that if the line were going to Mangere town centre it would be a lot less disruptive to build the line on the east side of Route 20 followed bythe east side of 20A than it would be to cross route 20 at the bridge and then cross route 20A to reach the town centre .

        2. The space is west side, MTC is to the east, but the station would involve substantial bridging of mway at this point and probably be elevated. The bridging alone helps repair the terrible severance issues caused by SH20. However there may be a good route that crosses the motorway before MTC (heading south) I haven’t looked at it for a while as we are waiting for the latest report on the route to be released.

          A key issue is station numbers and placement, there is an argument between 4,5, or 6. You know the usual debate between coverage and line speed. Contenders:
          Mangere Bridge
          Montgomery Rd
          New Terminal
          IIRC that makes for an average 1.2km spacing. And the closest two are Onehunga and Mangere Bridge but they are of course separated by the harbour and have their own catchments. I believe the current thinking favours five, dropping the Favona (Walmsey Rd-I think)

  6. Didn’t ARTA give Transit (now NZTA) $2.5m to allow the crossing to the future proofed for passenger rail? If that has not been achieved, would there be an argument that NZTA should come to the party with some money for a rail crossing.

    This was in 2007, right in the middle of Project Dart where double tracking was a key focus of upgrades to the Auckland network, so to only allow for a single track in this instance does seem to be a deliberate as opposed to an unthinking act.

    1. The only thing achieved with that money was that the piles of the new Manukau Harbour Crossing are strong enough to support a single track rail crossing in addition to the motorway itself. I can’t stand the term “future-proofed” either. It is always a half-arsed cop out for not doing something now.

  7. Here’s another thought re a Manukau Harbour crossing. I believe that NZTA is considering how to replace the “old” Mangere Bridge with a facility which will enable existing pedestrian/cycle and recreational uses of the facility to continue. Instinct tells me that having double tracking on a much shorter bridge more or less “at grade” leading to the existing causeway would be a far cheaper option for getting rail to the Mangere area than taking it under the “new” bridge on a single track. Going along with the idea that piecemeal extension of the network may be an easier “sell” than mega-projects, why not extend first just to Mangere Bridge when this bridge is constructed (don’t know their current thinking on timing)? If there are solid reasons why it’s impractical, I’d like to hear them. I posed the question at the time but was told that the current strategy was locked down, but I see no reason why it shouldn’t be revisited.

  8. What were people actually wanting here. A massive road bridge at twice the cost so that it could one day carry a rail line? Or a road bridge to blend in with the existing one that didn’t prevent a rail crossing or make it any harder?

    1. A bridge with a rail line on top of it and a stop at Mangere bridge, but it was an NZTA project so the best we could hope for was an allowance to build rail at some stage in the future.

    2. How does a dual track railway line make an 8-lane motorway bridge “twice as big”? Have a look at the Sydney Harbour Bridge.

      1. Yes have a look at the Sydney harbour bridge and how long the approach ramps are. Rail needs several km’s to get to that height. Not a few hundred meters.

    3. Dan – The point is that had the engineers who designed the thing thought about a rail line at the start, it wouldn’t have been twice the cost. The bridge still could have been designed to blend in with the existing one and the only major difference would have been that the piers were a bit further apart.

      It may have only cost a few mil extra to do it at that time, but by not doing it, we are consigned to having to spend considerably more to get the same result.

      1. I really don’t see how that would be possible given the grade of the existing bridge is too steep for rail. You would almost need a spiral loop each side just to get up to level.

        It’s like future proofing the next harbour crossing tunnels for rail. It makes $3 billion road tunnels turn into $5 billion road tunnels that still need fitting out for rail.

        1. Of course it won’t be on top of the bridge, the single track rail line is proposed to go through the middle of the piers (each pier is a set of two). Widening the gap between them would have enabled a double track to fit through. (the gap is 8.4m, the report states that a minimum of 9.7m was required).

          As for the Waitamata harbour crossing, the road only tunnel option was listed at $5.3b. Adding in rail capability isn’t expected to increase the cost by that much.

        2. Anyway that’s all backwards. The next Waitemata harbour crossing (after Skypath) is a rail tunnel sub 2billion, unless six useless traffic lanes are included adding another 5billion!

        3. The monster road tunnel future proofed for trains was $5B, if it were just for cars then it was $3B. Rail was $2B after a road only tunnel or about $3B on its own. After the $5B future proofed tunnel it was still about $1B to get a line from akoranga into the CRL.

        4. Once again, do some research before you post.

          Q5. What is the cost of each option?
          The road bridge option will cost around $3.9 billion and a road tunnel $5.3 billion in 2010 dollars – a difference of $1.4 billion. [Both options exclude rail tunnels, which have a cost estimate of an additional $1.6 billion]. This is upper end of the range of cost estimates [refer Form Assessment Study Report, section 17.costs estimates, for details of the range of cost estimates].

          Whatever option is chosen, an additional crossing of the Waitemata Harbour will be one of New Zealand’s largest infrastructure projects.

        5. So if you are so sure of those figures, can you explain to us why this tunnel will cost about 4 times more than interview yet it’s only about 50% longer?

          And why the rail tunnel that is twice as long as the CRL comes in cheaper?

        6. The comparison to the CRL is fairly easy, a big part of the CRL costs is in the stations, the AWHC rail tunnel only has one station at Wynyard which is likely where the TBM would be launched from anyway.

          As for the road tunnel costs compared to Waterview, perhaps it is to do with a more challenging build.

        7. It actually has two stations, one being Aoteo which will need are large rebuild while it’s operating.

          Also waterview has more complex ground conditions. The harbour crossing has one simple easy to dig rock all it way along.

        8. Well I would have thought any rail bridge would need to provide the same clearance as the road bridge. Or is rail exempt from future proofing for other modes such as ships?

          Also rail to the north shore will be well over $2 billion. Significantly more so if it were built before the road component.

        9. Do you live in Auckland and if so have you ever been to this area, ships can’t get into the harbour thank to the old bridge that is now used as a cycleway and fishing spot.

          As for rail to the shore, the latest AWHC study costed it at $1.6b for a separate tunnel while another report listed getting it to Albany using the busway corridor at $2.5b all up.

          Please do some research

        10. The rail bridge only needs to provide the same clearance as the old Mangere bridge, which is a lot lower. Ships don’t have any reason to come past the bridge: the port is to the west, and the water isn’t really deep enough. In any case, the bridge is future proofed for a rail line at that height – the problem is that it’s only single-track.

        11. You clearly don’t know what future proofed means if you think blocking off a body of water for the rest of time counts

          And yes I now of the costings as I have seen the real ones, not just the manipulated ones that only cover part of the actual cost. Much like the CRL which costs about $2B yet only 2 years ago was being sold for $1B.

        12. Dan again – under your argument, you would have to admit that NZTA didn’t do ANY future-proofing in that case, because their proposal does have the bridge on the lower level.

          And we could argue that deciding to NOT allow larger craft (larger than single-deck ferries and pleasure craft) into the Mangere Inlet is a more sensible (and lower-impact) decision to NOT future-proof than many others that have been made, conciously or unconciously, in our transport history. Sure, if we ever dig the canal to the Tamaki River to enable ocean-to-ocean crossing. What is mroe likely – that, or airport rail?

        13. What about simple high mart yachts? Should they be fenced out for the rest of time so a rail project can save some money and make an unsightly bridge?

        14. Dan, the inner harbour is, as others have said, blocked by the Old Mangere Bridge, which is only about a metre above the surface at high tide. There has been no entrance to the inner harbour for anything larger than a dinghy (and not even for those at high tide) for over a century; the first bridge was opened in 1875 and was replaced by the current “Old” bridge in 1914.

          A rail bridge doesn’t need to be as elevated as the road bridge, it only needs to be clear of the highest possible storm tide. The only reason the new road bridge is so high is that it’s run between two points that are elevated above the surrounding area.

          It’s pretty clear that you have no familiarity with this area whatsoever, otherwise you wouldn’t be presenting such ignorant objections.

        15. Yes. Because high-masted yachts in 2013 and onward serve no purpose than pleasure, and its perfectly valid to exclude them from an area that they aren’t in today, and need not be in tomorrow, if that choice can save dozens or hundreds of millions. It is considered a trade-off decision, and I don’t think its a hard one. If those industrial areas surrounding the inlet ever get developed into fancy villa areas, people don’t need to dredge channels through the mangroves to their yachts either, the poor fellows will just have to keep their boats further away from their villas.

          And stop talking of the rest of time, please. As if whatever gets built here will last longer than earth…

        16. Keep your cool Mr cloud. The road bridge actually raises up on both approachs on its own accord to clear a future proofed navigation channel.

          The old bridge was left there as nobody currently needed the area and so it was left as protection. Now it has turned into a community area. When it gets removed a new area will open up for boats.

        17. The old motorway road bridge was presumably raised originally because people were still a lot more serious about the canal being built. These days, nobody is taking that serious anymore. The fact that the new bridge next to it was also built to that height is likely to have had as much to do with visual impact, and the difficulty of tying into a motorway that was already raised up anyway, as with keeping the clearance free.

          NZTA is unlikely to WANT to spend lots of money on future-proofing for coastal shipping either, unless somebody requires it of them, yet you seem to say its good that they did that, yet you don’t care that they didn’t future-proof for rail well?

          What is the difference here? Do you have a yacht and would like to sail there, dan again? I would love to do so too, but not if Aucklanders have to pay extra dozens or hundreds of millions just to enable that AND airport rail.

        18. My point is that there is not all that much that could be done to future proof the road bridge. If kiwirail is able to get away with building a low level bridge there they have swarms of potential 2 track alignments to choose from.

          For myself I would much rather they build a tunnel rather than further ruin the look of the area.

        19. It’s a good thing the road tunnels are completely unnecessary, then, since it means that the $1.5 billion rail tunnel isn’t turned into a $5 billion tunnel.

  9. Ok, so now that unfortunately it has been built like that, now what?

    One idea would be, depending on costs, to build the single track bridge for now on the B3 alignment, then come back and build the second (and third?) track on alignment C…

    1. yup, or build single track one-way now, then two track bridge later, and leave the initial single track as a freight bypass to access Onehunga port from north and south. Perhaps?

  10. It isn’t rocket science, all that is needed is just transport amenity that isn’t moronically monomodal.

    But I guess seen as the geniuses in charge in NZ looked at the Sydney Harbour Bridge and said lets have one of those but we’ll make it better by hacking off everything except the vehicle amenity, why would they do anything better at the other harbour?

    Oh but they did add the nasty rapists-delight pedestrian slot under the eight lanes of traffic.

    The old bridge has saved part of their shame as it is a wonderful wide ‘place’ a perfect example of really good pedestrian/cycling/fishing/hanging out shared space that should be the model for all pedestrian spaces. NZTA always make ped bridges too narrow as of course they only ever think about movement never being somewhere.

    And we will now have to add the missing rail bridge between. That’s all.

    1. The old Mangere bridge will go soon. They don’t like doing maintenance on it. It will be replaced with something, nobody I talk to is sure what.

      Notice that the consultation was not on the options. The consultation was narrowly framed in service of a particular outcome, and the only input the public were invited to give was how best to implement that outcome.

      1. The NZTA’s project page still says the replacement will be six metres wide, which is less than half the current width of approximately 14 metres. That’s bloody narrow when you’re talking about three metres for bicycle lanes (they’re going with the proper 1.5m per lane, right?!) and still have to allow space on both sides for people to fish without their rods and tackle becoming hazardous to cyclists and pedestrians.

        1. Six metres wouldn’t be so bad, if it was a brand-new bridge. But as Patrick mentioned, the old bridge, by virtue of its great width that had become a free-for-all for peds and cyclists, had a specific “place” function, beyond the transport function, and that is what is at risk of being lost.

        2. Whoever came up with the width has clearly not spent any time on the existing structure. The fishers legitimately need a couple of metres of space to be able to work with their rods without endangering others, and they legitimately need to change which side they use based on the tide; that’s four metres, which use will change throughout the day and at inconsistent times.
          Cyclists need at least a metre in each direction, or 1.5m if NZTA’s guidelines on bicycle facilities are followed. That’s another two or three metres, taking us up to or beyond the proposed width of the replacement bridge.

          If the fishers and pedestrians swap sides depending on the tide all will be well, but I can see it being the bicyclists who are forced to compromise (as per usual) with no consideration for the bridge’s place as part of a long-distance route that’s used by serious training riders who will, not unreasonably, expect to be able to maintain their 20-plus-km/h speeds on the new structure. I just don’t see six metres as being even remotely wide enough for a replacement.

          Even if this was a new bridge it would be exceptionally narrow for how busy it gets during summer weekends, though I guess it just wouldn’t be so busy since it wouldn’t be such an attractive place to go.

        3. Even if this was a new bridge it would be exceptionally narrow for how busy it gets during summer weekends, though I guess it just wouldn’t be so busy since it wouldn’t be such an attractive place to go.

          There’s the tragedy. An extensively utilised, attractive, user-friendly piece of existing pedestrian, cyclist, and other recreational infrastructure with significant historic value is to be destroyed. It links two communities. In its place will be created something which lacks much of the above, and does the rest more poorly.

          If NZTA wasn’t so concerned with subsidising massively expensive unnecessary roads, none of this would be necessary. I also have no doubt that if this structure was in Devonport or Parnell, or a similar suburb where those with more power reside, it would be retained in its entirety.

        4. George I doubt it would make a huge diff to their budgets to do it well it’s just that it seems to be beyond their comprehension. Any chance, for example, that the existing bridge could be structurally upgraded? Or just replaced where it it needs to be to the same scale. As it is working brilliantly now.

        5. Patrick, the current bridge has suffered two ship strikes (including one in 2005) so I think there are some big questions about its long-term structural integrity. The costs of appropriate engineering to ensure it’s safe are probably higher than complete replacement, and it’s not like it’s an attractive example of bridge building. The NZTA project page implies that the replacement will be built higher off the water, allowing more use by surface craft, and that it will be built further up the harbour so that the risk of ship strike in future is mitigated (the 2005 incident was a vessel that was under power, with tug assistance and full bow thruster application, but still couldn’t beat the wind) while retaining the current bridge’s navigation lights.

  11. If a single track can fit between the two pillars shown in Matt L’s photo above, simply build a third pillar to the left with similar spacing (which I assume would be to the east) and put the second track between that and the existing left pillar. Unfortunate, but what about providing a dedicated cycling/walking path on top of the third pillar? Silver linings & all.

    1. No need for a new path for pedestrians and bicyclists, there’s already a good route across the old bridge and through the corridor (Patrick’s “rapist’s delight” above) beneath the new bridge. We don’t need a third crossing option within a linear distance of less than a kilometre.

  12. Could someone confirm that the Onehunga Line itself – which is single-track, after all – doesn’t have any serious issues with being double-tracked? Is the corridor wide enough?

    And for those structural engineers here, an easy question: Could one put an third set of piles just to the north of the new bridge so they could carry the extra track, spanning between the new piles and the northern motorway bridge piles?

    1. I believe there’s some minor property acquisition to widen the corridor, but most of the Onehunga Line runs adjacent to industrial property where the loss of a couple of metres from the boundary is not going to be a significant imposition (or hugely costly to purchase). The tricky bit is right at the last bend before the station, where there are apartments built almost up to the tracks on one side and a storage unit facility to the other. I’m not sure if there’s sufficient width through there for double-tracking, but someone on here will know.

        1. Yeah, those are a whole other kettle of fish. There are five level crossings, including two within 200m of each other, and they’ll have to be grade-separated if the line is to be double-tracked and given appropriate service levels without some significant impacts on what is a very high level of industrial traffic. Dealing with those is not a corridor width issue, though. It will, however, be horrendously disruptive to the Onehunga Line while those crossings are separated, because the road configurations make them very poor candidates for overbridges because all bar one (Victoria Street) are immediately adjacent to intersections with business premises on the corners and high levels of through traffic on the road that’s parallel to the track.

        2. Not really the case that they’ll have to be grade separate to handle a 6tph each way. Ideal but not necessary. It depends somewhat on what is done with Nielson St to improve truck traffic which would influence any decisions around closures. Otherwise it looks like trenching the track at least in part is probably the most direct way to grade separate…. not cheap.

  13. Can’t see how this is a failing of transit. They are building roading infrastructure. If the job required to be future proofed for rail that would have been the job of
    ARTA to inform what the requirements were. Sounds as if they were left hanging. And Then what were the rail future proof specifications? Again, sound like they were left in the dark.

    What became of ARTA? Oh, that’s right, they were abolished. Not what would happen to high performing organisation. And for government agency to have judged to have failed, they must have been rubbish.

    Stop the hating and think about the process.

    Question: was there meetings between transit and ARTA prior to awarding of the contract? If so, why was no understanding of future needs

    1. My understanding is that ARTA only became involved after the consent process started and Transit agreed to include rail, but by that time the majority of the design was done and they refused to make any real changes to it.

      As for your comment on ARTA, wouldn’t that also apply to Transit who are also not longer around. ARTA was added to and morphed into AT just as Transit became the NZTA.

  14. > What became of ARTA? Oh, that’s right, they were abolished. Not what would happen to high performing organisation. And for government agency to have judged to have failed, they must have been rubbish.

    Oh yeepers, you really don’t know ANYTHING about politics, or power relationships, especially unequal ones, do you?

    In fact, your comment is a perfect example of “might makes right” and “right or wrong, my country” attitudes.

  15. If they’re replacing the old Mangere bridge then it would make sense to build the double track option and add the pedestrian and cycle crossing to that, rather than demolish one bridge and replace it with two…

    1. Karlos, it would – but there’s no money in the budget for sensible solutions. Worse, NZTA is FORBIDDEN from using their money for rail.

  16. But WHY was ARTA not involved pre consenting? That office was huge, there must have been a cast of hundreds.

    1. Are you serious? Are you really asking a question, or just trying to get responses? Why are you surprised that a motorway-focused National Government-level department would ignore attempts by a local government-department known to be PT-focused, especially when that input was likely to cost the motorway builders big-time money?

      That is how politics and power work. If you don’t like someone’s input, you ignore or marginalise it until you can’t anymore, because someone forces you to listen to it. And then you can still do a half-job, while claiming you did what they wanted, and have future-proofed the bridge!

      1. When the work was underway it wasn’t National in charge. The planning and consenting for the new road bridge commenced under Labour, though even then Transit was very heavily focused on roads and the Onehunga Line was still a disused length of track that ran to nowhere.

        1. I did not say “National” as in party. My sentence clearly contrasted “National Government”-level with “Local government”-level. Never found a good way to clearly distinguish the two.

        2. The normal terms are “central government” and “local government”. If you capitalise the National it gets particularly confusing.

  17. The optimist in me thinks it’s ultimately useful having SH20 Mangere Bridge as an clear, recent example of poor transport planning. Sure it’ll cost us $50-$100 million more in the long run, but we’ll deal with it. The real battle is making sure that every major highway upgrade from now on considers (and subsequently makes appropriate allowance for) the future role of rapid transit in that corridor. SH16 I’m looking at you …

    It’s also important to acknowledge that the bridge itself has delivered some important benefits – it has greatly alleviated congestion on SH20 and was useful during RWC. It also does match the curvature of the existing bridge. On balance it’s probably still had a positive impact even if it in doing so it (almost deliberately) screwed rail and seems to be a blunt way of providing for local connectivity between MB and ONE.

    For the highway men the take-away message, as they say, is “must try harder.” Time for some more chocolate methinks …

    1. Okay Stu, what happy pills did YOU take today??? 😉

      I can’t see how it helped – at least in any way meriting the huge cost – during the RWC for example. I still think that Joshua Arbury’s cutting comment about “Helping all the RWC tourists who will bring their cars on the plane” went right to the heart of that particular piece of hogwash.

      1. ah but I wouldn’t underestimate the level of increased bus, shuttle, and taxi traffic associated with RWC. But worth checking the numbers as it might be hogwash.

        In the meantime I’m going to maintain my happy state of delusion 😉

    2. Stu, it would be fair to say the SH16 boat has pretty much sailed too. So no lessons were learnt it would seem.

      1. yes well that’s true. In the meantime I’ve eaten all the chocolate and all the icecream so I guess it’s time to crack open a moa.

  18. It is not the job of transit to design for future rail when it’s not their business and they would have NO IDEA what the requirements would be. If they were told to future proof but not given a specification you think they, as road builders, would know? That’s where inter organisational relations come into play.
    You can just imAgine, being told to future proof and that’s it. Don’t bitch about the outcome unless it was not delivered to scope. Bet you dime to the dozen there was no scope.

    1. Tend to agree with you actually. ARTA weren’t pushing for the rail option until late in the piece, when Mike Lee from the ARC told them to sort it out. And Manukau City Council could have been pushing for it from the outset, but they didn’t in spite of CBT presenting the idea to them in plenty of time( circa 2004 from memory) It wasn’t until CBT went to the Environment Court (against Transit and MCC) that a corridor was preserved on the western side of SH20 as far as Walmsley Rd for rail. Where the hell is that SMART “mult-modal” study at now anyway? In some kind of bureaucratic limbo no doubt.

      1. I was working at ARTA during this process and was involved in this work. Option B was insisted upon by Mike Lee for political reasons to force Transit to future proof a rail corridor along SH20, even though it was an inferior solution than option C, which could have been built at a later date without affecting the road bridge. Having said that I doubt that option B will ever be built as it won’t take much analysis to show that a double track bridge will be operationally necessary.

    2. Yeah I also have to agree with Sweet As here. The NZTA had a project to deliver which they did.. and as with all infrastructure projects they stuck to the agreed scope. Stu is also right, the bridge itself is a massive improvement for those of us who drive over it.

      The trouble isn’t with delivering the projects. Charles Landry was interviewed on the radio just now.. well worth checking out the podcast. He had a nice line on building development projects, but it could equally apply to infrastructure projects.. “you have to decide is Auckland a city of projects or is Auckland the project?”

  19. I said at the time that some were claiming it was future proofed for rail, that it wasn’t, but nobody believed me. Both options B and C require entirely new bridges, with their own piers, for the railway. It’s quite pathetic that any option should involve curves. The track should be straight out of Onehunga, across the harbour, and then either stay on the east side of the motorway all the way, or pass beneath it further south, toward the motorway junction.

    1. Sorry, to clarify, the option B doesn’t require piers into the ground, but it requires cantilevered piers, which are every bit as large and expensive as if they did have to go into the ground. I.e., there’s no cost saving but connecting the rail bridge to the motorway bridge.

      1. Hi Geoff – I also thought that at first glance, it required cantilevered spans out from one side of the bridge. Then I noted that the image on the photo shows only the “old” Manukau motorway bridge, the new one appears directly above the proposed rail tracks…ie doubles car lanes from 4 to 8. The single track would be slung under the new motorway bridge between the piers…not sure if that counts as cantilevered or not.

        One further aspect that does concern me is that the rail track pops out on the west side of the bridge in Mangere. The upside is that it is closer to residential centres, saving multiple Ellerslie type motorway pedestrian overbridges to get to a rail corridor positioned on the East side of the motorway. further south. A further upside is that at Moyle Park it is an easy turn toward the airport for the rail corridor.

        The downside is that in the area near the Coronation Road and Walmsley Road overbridges there are roads at a range of gradient and grade levels that may interfere with a rail corridor positioned to the west. At ground level there is a large area of swamp. There may be a potential problem threading a rail corridor through without expensive works providing a cutting through the swamp, and/or modifying the off-ramps and overbridges. In addition, the motorway itself gets pretty close to residential properties along the western edge of the motorway corridor, from memory closer than the motorway is to the factories along the eastern edge. A case to move the entire motorway over by a lane? Which if it does prove necessary is another cost to be born by rail which could have been avoided with better planning?

        It will be interesting to see what comes out in the “SMART” multi modal study. I will be disappointed if the study doesn’t address the nuts and bolts of constructing a credible rail corridor.

  20. Sorry but have to take exception to Geoff s comments. Again, a misunderstanding of what the delivery entailed. What does “future proof” mean? It doesn’t mean build half of something (with out knowing what the “something” is). If future options have not been precluded that is future proofed. Perhaps peps on this site would have preferred transit have a punt at a rail crossing without a scooby-do of the unspecified outcomes? It’s only money after all.

    1. Future proof at the bare minimum simply means not closing off options. Including not making them unnecessarily expensive (because, of course, anything is possible with enough money and effort). Doesn’t look too hard here to have arranged the structure to allow a future rail route of standard dimensions and directness. A little serious effort would have been good.

      A good example to raise Matt, hopefully this is a reminder to those working for us to think a little more beyond the immediate task when designing the project scope of large and expensive bits of kit like this.

      A real sign of the times eh? Hopefully we are doing things better now, especially with all this multi-modal talk by politicians and agencies. And how much am I pleased to see the end of the dreadful MCC, what a mess they left us with.

    2. I should have been a bit clearer as to the relevance and context of my comment. A couple of years ago, the rail crossing of the harbour was topical with those of us debating the merits of airport rail via Onehunga, vs airport rail vi Wiri. I favour Wiri, as it’s shorter, cheaper and enables trains from all lines to use it (from north, from the east, from Manukau and from the south). One of the counter arguments put to me was that the cost of the harbour crossing was no longer a significant factor because NZTA had built the motorway piers with rail in mind. Somehow the belief was that the rest of the rail bridge would be simple and cheap. I disagreed entirely. The truth is, you may as well build a whole new standalone rail bridge, as the “future proofing” did not involve anything that will make any noticable dent in the construction cost of the rail bridge.

      1. My take on the reason to pursue the airport link from the North is that there are very good potential residential ridership catchment areas in Mangere Bridge and Mangere Central along with strong local links to Onehunga. There are employment areas with moderate potential areas through the factories on the east side of the corridor, Kirkbridge Road Area and the recently developed light industrial areas closer to the airport. The airport itself is an employment area with high potential for commuters. It is known that the airport draws considerable employment from Mangere through to Onehunga residential areas.

        Overseas examples demonstrate that airport rail links work best when they are also providing a local commuter role. This spreads the overheads. Looking at specific traffic sources from the airport, the line through Onehunga avoids the congested railway corridor through Westfield and offers the more direct link into the city for airport express passengers. As a supplementary source of passenger riders for the overall Onehunga-Airport corridor, Ellerslie is a major station. Growth out of Ellerslie has been created by the enhanced frequencies made possible by the Onehunga corridor.

        By contrast, what can a link from Wiri offer? Through traffic to/from Manukau City, Papakura, Pukekohe and Hamilton? The whole idea of an sort of Auckland-Hamilton rail service is very contentious at present as is the status of Manukau City…traffic source or destination? One other thing, a link from Wiri would also require a bridge as does the current road link between the airport and Wiri. So not too many cost savings there and in terms of potential sources of traffic, vastly inferior.

        In short, a landslide win to the rail corridor from the Airport north through Mangere and Onehunga.

        1. Bingo. Between Onehunga and the Airport are some residential populations that are woefully served by public transport and the second-densest employment cluster (after the CBD) in the region in the area of Airport Oaks. Rail from Wiri will pass through a whole lot of nothingness.

        2. Yep, even if it costs $100-200m more to go via Onehunga, it has many more benefits from adding new stations to the network. I suspect there will be more patronage to/from those stations than the airport itself.

  21. Not too hard to arrange the structure to allow a future rail route? Give me strength . The contract as was discussed earlier had been awarded. It would have been an absolute nightmare, and the construction outfit would have been laughing their arses off as they rolled in the mountains of money. There would have been delays to the entire critical path of the whole job.

    This is NOT a MCC balls up.

    Mike Lee and the heads of ARTA should have been all over this. This is the level at which the PT requirement discussions should have initially been held at. How would MCC be responsible for defining a strategic regional PT rail alignment?

    1. Perhaps you were involved, getting rather defensive there… If you read my comment with a little less spleen you will see that I carefully aim it at those designing the scope of the whole project, not expecting those lower down the food chain to have responsibility for strategic issues. Yes and that includes the territorial authority of the time. Now I would expect NZTA, AT, and AC to have that vision… and am hoping that they do. This is now well spilt milk, and will require an expensive work round. But don’t expect it to be forgotten. Not sweet as.

      1. Not involved, nothing more than a person who suffers transport issues in the city and read this blog.
        I just came to add some balance, like I think Dan Again attempts for time to time.
        You can at least see this was not an MCC failing, or a simple fix thwarted by the evil road diggers?
        I agree This is very much spilt milk , but then, I assume your comment is equally aimed at Matt?

        This blog is fantastic, and i think everyone appreciates what must be a huge effort from the team behind the scenes. just sometimes it is a circle jerk. for best outcomes for the city should be an exchange of ideas. One that it takes all view points. I for one don’t act like I know all the answers ;0)

        1. To be fair, I don’t blame the engineers who came up with the designs, they were doing what was asked of them and when told to future proof they did what did what they realistically could. It probably has more to do with those at higher levels who set the scope not thinking ahead enough. What I was trying to get at with my last paragraph in particular is not assigning blame but saying that we need to use examples like this to do better in the future.

          An example where this seems to be happening more is with the AWHC. Now I have stated plenty I times that I don’t agree with another road crossing but at this stage it is proceeding. When the latest study came out the NZTA had their road crossing tunnel and a separate rail tunnel. Afterwards it was pointed out that overseas cities, like in Shanghai have built road tunnels with the same dimensions and been able to include a rail line in the same space. Since that time I have heard that this is now what the NZTA are planning for. If we have to have a new road tunnel then it does make sense to include rail in it rather than have a separate tunnel with increased costs (although I’m hoping for a rail only tunnel initially and then seeing if there is still demand for a road tunnel).

        2. Surely it’d cost a hell of a lot more to bore a tunnel of sufficient size to carry at least four lanes of vehicle traffic (dual-lane bi-di) and two rail tracks than just a tunnel for two rail tracks? The machine would have to be significantly larger, and the amount of liner material would be exponentially greater. I just don’t see it as economically wise to bore a tunnel that can be road-plus-rail and then only commission the rail part.

        3. They won’t bore one tunnel but two, one each direction. The plan is for three lanes each way but the thing is there is roughly enough space below the road deck for a train line (where the cable tunnel is.

          If we went for a rail tunnel only, it would be just that, a rail tunnel and if a road crossing was needed in the future, a separate tunnel would be dug.

        4. That’s what I was recalling, if a little off. That tunnel would be enormously more expensive than rail-alone, so there’s no conceivable way it would be done and then not completed as a road tunnel. Never happen in a million years. Either we get rail-only or we get a full-blown multi-mode tunnel, because as much as I don’t think we need a replacement road crossing I would be beyond apoplectic if multiple billions were spent building that diagrammed cross-section and it was then only used for rail. That would be a more-criminal waste of money than the RODS, and not even the Greens would support such nonsense if the only way to get rail across the Harbour was as part of a multi-modal tunnel.

        5. I agree Cloudy Matt, rail only across the harbour is considerably cheaper both to build and to operate than any road version. Being both a smaller diameter and requiring much less elaborate ventilation as only electric vehicles will use it.

          Certainly other work will be needed to link this line with the rest of the network, but then that brings additional benefits, as Wynyard Quarter in particular needs connecting as it grows. Also the road crossing itself leads inevitably to additional expensive network expansions as it surely can only be justified by a massive increase in driving, presumably at the expensive of Transit systems.

          The wider cost to society of expanding the ability to drive between the city and Akoranga would be horrendous. It can’t happen.

  22. Just wondering who else here uses the old Mangere Bridge or for that matter has walked under the old motorway bridge? I walk over the old bridge most work days and it is going to be tricky if it gets replaced by only a 6m one. Especially as a number of scooters and the odd motorbike seem to think they qualify as bicycles. As for the walkway under the old motorway bridge it is in a shocking state and I honestly don’t feel safe crossing it. So removing the old bridge and not replacing it is not an option in my opinion. As for single tracking to Mangere Bridge it is not perfect but I would gladdy have that than nothing.

    1. I bicycle the old bridge regularly, and occasionally take the new bridge but my road tyres are not good on the gravel section of the path on the Mangere end (yes, really, a gravel path!) so I don’t do it often. I don’t mind scooters using the old bridge, but it’s a bit cheeky for motorcycles given how close the motorway ramps are.
      As I’ve said above, what’s planned is less than half the width of what it’s replacing, and appears to have been designed by someone who has zero familiarity with the amenity provided at present. I wish I’d become aware of the project before submissions closed, because it’s something about which I would definitely have put in my oar.

      1. Also maybe just just not aware of the local culture either, it’s a more hangin’ out place than other parts of our fair city. Please don’t ruin it NZTA; please learn to think place as well as movement, after all FFS, all that movement is surely to get somewhere, isn’t it?

      2. > on the gravel section of the path on the Mangere end (yes, really, a gravel path!)

        Actually, from memory that path looked to me like some sort of sealed path that had a lot of vehicle traffic until the surface broke apart, and was never repaired…

        1. I ride this route daily and share the love between the two bridges. It is definitely gravel, but this might be on a base of broken asphalt. I’ll take a photo this afternoon. I did not get a free coffee this morning 🙁

        2. The bit I’m meaning has gravel laid on it rather than just being a broken surface (unlike the old bridge), and it really stands out because it joins the bridge corridor to beautiful, smooth concrete paths. I thought it was only a bit of unfinished business the first time I rode it because the new bridge hadn’t long been open, but it was still gravel earlier this summer which was the last time I rode it. For obvious reasons I try to avoid gravel paths because I ride a road bike.

  23. I’ve heard that a driver on this ‘future-proofing’ was Labour President Mike Williams, added to the Transit board as a political overseer to keep an extra eye on them. Soon after appointment he queried Transit on what they were doing about rail to the airport, and the answer was nothing! Given that it was at a very late stage as first mentioned, all that could be done it seems was this half baked solution outlined above. One lane would be possible for this stretch, but would require excellent timetabling, and a bunch of operational hassle for a long time to come. Tough decision for an extra $100 million.

  24. Yeah the old bridge is a lot more than and ends to a mean. Also AT have a bike pit stop at the village end of the causeway. This morning.

    1. Bike stop? Really? I assume it’s mobile rather than something that’s just been installed, since I rode through there twice on Monday morning and didn’t notice anything.

      1. Yes it was mobile. I have never seen one before. The guy stationed there must have setup up pretty early as it was ready by 6:20am when I went by. As I was walking I was not able to see what it was about.

        1. That must have been one of the cycling promotions things that AT is putting on. If you had come by a little later, you might have scored yourself a free coffee.

  25. Has anyone answered the question about the concept of having one track under the motorway bridge and adding a second track alongside on a third set of pillars? If feasible this seems to be a good, but unexplored, option.

  26. What about a tramway double tracked from the Airport over the old bridge and along Manukau road down Parnell to the Ferry Buildings?
    Mangare Bridge, well Ports of auckland can put up large pilings well clear of the structure to fender off any out of control ship

    1. Well a tram on existing roads is not much different from a bus is it? It would still be stuck in traffic, just got steel wheels instead of rubber. If we’re going to spend the money on rails we really should make sure it has its own Right of Way so it offers the speed and efficiency as well as the appeal and environmental benefits of electric drive.

      In other words its’s the corridor that provides most of the value in Transit amenity, the great thing about a train line is that it HAS to be grade separate along all of its route so if we build rail we will certainly get that quality, whereas with a tram or a bus service there is way too much likelihood that the quality of the right of way will be compromised.

    2. The old bridge isn’t considered to be safe for continued pedestrian use in the long term, never mind putting many tonnes of moving metal across it. It needs to be replaced.
      The old bridge is also in very close proximity to the dock. Trying to put deep-sunk piles in far enough out to matter would be taking space away from ships trying to manoeuvre in and out of the berth.

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