The release of the CRL designation documents has definitely helped clarify a few key facts surrounding the CRL. One of the biggest happens to be that the Inner West Interchange (IWI) has been dropped in favour of the Eastern link and that was picked up by the Herald yesterday. With that interchange gone it should mean AT can now hopefully start to put a bit of effort into what service pattern we can expect to see. I think that if they get that right, it is something they should be able to start using to help promote the project. It would help to show that the it isn’t about looping trains around and around in circles or just about improving access to the city centre but that by routing trains through the tunnel that we can open up new destinations.

First for the sake of comparison, here is my understanding as to the thinking was with the IWI. It was largely driven by the fact that the majority of passengers in the city centre would be going to either Aotea or Britomart so the focus was on getting them to those destinations first. That means sending all trains from the southern and eastern lines through to Britomart and then up the tunnel on to Aotea and eventually the IWI. Eastern line trains would then head out west to Swanson while Southern and Onehunga line trains would terminate at the the IWI. They would then have to travel back down the CRL, likely mostly empty before either going to a stabling yard to be built at the strand or back out to Onehunga or Papakura. Off peak a shuttle would run between the IWI and Newmarket however during the peak it would be extended to Henderson. Just to make things even more confusing there would also be a handful of trains from the west at peak times that would do one run then terminate at Britomart before going to the previously mentioned strand stabling depot. For the sake of making it easier to show, I have shown this without special peak services.

IWI routing

So what can we do now that we know the eastern link instead of the IWI is being designated. By sending the Onehunga trains via Grafton it then gives us two routes that enter at the southern end and two at the northern end. Linking then together so they don’t end up going back on themselves means the western and southern lines get joined while the eastern and Onehunga form the second line. People from the west who want to get to Newmarket would still be able to do so either be staying on the train or swapping at the new Newton station like described in this post. Any trains that are not needed off peak would likely finish their run out to the suburbs before heading to a nearby stabling depot (there are now a number which fairly close to end of each of the major lines).

Post CRL pattern

Going a step further, I think the next rail project off the rank shouldn’t be rail to the airport but the comparatively cheep branch line to Mt Roskill. The reason for this is that the route is all ready designated (was done in the 1940s) while the more recent motorway works have included providing for the line at most places. With the exception of Dominion Rd, all bridges have a clear space or extra span for the rail corridor so the line should be fairly easy to build. It may not seen that important but the route ends up serving a couple of useful purposes. Stations at Dominion Rd and Stoddard Rd could serve as a focal point for the local buses from the southern end of the isthmus. That should either help free them up for their run to the city and/or allow the number of buses that need to run all the way to the city centre to be reduced. The other big benefit would be that services that run on this branch would add capacity on the inner parts of the Western line at the parts it is usually at its busiest and the area most likely to benefit from the CRL due to the vastly reduced time to the city centre.

The question of course is where you would run this line to and when you think about other major PT developments that are going on, and you instantly turn to Panmure. With the AMETI busway feeding into the Panmure station having extra capacity, and frequency is probably going to be extremely useful. A turn back station at Panmure (or possibly Sylvia Park) which is just used by the driver to change ends, would allow those trains to terminate here without getting in the way of other trains using the tracks.

Mt Roskill + CRL patternWhat we end up with is a network with three main lines going West, East and South and with a series of short lines that work to boost capacity on the inner parts of the network. The Mt Roskill branch would also allow us to look at other through routing options but I won’t explore that further in this post.

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  1. The other option is to connect the Eastern with the Mt Roskill branch and have Panmure to Onehunga via CRL and Grafton as the other line. That would provide a direct link between Manukau and the western line’s inner section.

  2. This just shows my stupidity, but for the life of me I have not been able to find out where the stations on the CRL will be. Is there someplace that will show me? I can’t even figure out what the route will be – nor when it is expected to be active.


        1. I wonder where, more precisely, that Newton station would be located.

          Of course, the plan says five and a half years, so I don’t need to get too hot and bothered about it yet 🙂


  3. Good to see you included future stations between Papakura and Pukekohe. But in the future services must be run out to Huapai and Waimauku. Any reason why that never appeared on your “future” maps?

    1. Why must they be run out of Huapai and Waimauku? The problem is that by the time you get to those areas you have taken such an out of the way route that is much slower than alternatives.

      1. Yes I agree, just because the main north freight line was run out that way doesn’t necessarily make it a good place for passenger services. Currently there are pretty few residents out that way, and even if there was a lot of growth the line is still only really useful for getting to Henderson or maybe New Lynn. The journey through to the City Centre and links to other lines is very circuitous and long from Huapai. The new bus network in the RPTP really sorts out the public transport for the northwest, and the proposed Northwest busway would only improve it further.

      2. Plus, there’s not much growth on the horizon for Waimauku, as the plans to massively expand it were canned. Kumeu/ Huapai are marked for growth, though.

    1. Effectively it gets relocated 300m north to Newton Station. The Mt Eden station is actually retained, but it wouldn’t be accessible on any train going to or from the CRL as it sits in the third leg of the main junction. I guess they could service it with trains that run from the western line to Newmarket directly, but that might be a pretty useless service.

      1. I think one of the major faults of the Auckland Train service (and generally all PT) is the Star System design assuming that everyone wants to go to CBD. That will not increase use as for non work related travel PT remains still pretty useless and very unhandy if you have to change. Even the new proposed network does not take this into account. What about a line going via old connection of the Western line down to east using the Strand station (avoiding britomar, the infrastructure is already there, and this could easily connect west with east south, even during the time CRL is built. Im travelling the western line, and in fact about half of the train is empty after Grafton and Newmarket, so i guess the need for this connection is given. Even City access is given using the Strand.

  4. Given the yellow line is a hypothetical future state beyond even the CRL it’s a long term problem at most, but it seems unfortunate that all the key interchange stations (Britomart, Newton, Newmarket) are slightly away from the actual line interchanges. Is this a natural situation for rail lines, where you want stations on straight pieces of track and intersections are typically curved or a consequence of the particular constraints of the existing rail lines in Auckland? In the picture above, Grafton and Parnell stations would be better served (and the route diagram would look prettier) if the yellow line ran through them to Britomart but it would make the line less attractive for most passengers if Grafton was an interchange and the alternative of reversing trains at Newton is presumably impractical?

  5. Thanks Matt for the diagrams. I know that this has probably been explained a dozen times here, but I’ve been scratching my head the last few days trying to figure out what the Inner West station was supposed to do if we had built it. I’ve also been wondering why you wouldn’t just route ALL the trains in a sort of lower case omega shape around the CBD and just leave the southern end of the omega open without needing to build the east-facing junction south of K-Rd. The first two diagrams explain things clearly, and the topology shown in the second diagram is indisputably more elegant and efficient than in the first.

    I don’t see how a Mt Roskill extension can be prioritised, politically. Brown campaigned on the CBD Link, the airport line, and rail to the North Shore in that order. Those were the promises and that’s what people voted for. I don’t see how you could introduce and prioritise new projects without election promises being seen to be broken.

    1. One question: How does freight fit in to the equation? Presumably north-south freight will route south of the CBD and the section of rail that Mt Eden station currently sits on will be retained for this use. It’d be a bit odd to have freight trains coming through Britomart and Aotea.

    2. It is important to serve Grafton Station. Freight trains will not go through CRL, they will use existing tracks.

      1. If my experience commuting on the Western line to the med school is anything to go by, a lot of people coming from the west alight at Grafton. At peak hours there’s queuing for the stairs to get on to Park Rd.

        1. Yes a lot of people get off at Grafton and Newmarket but as a total number, that is not likely to change hugely in the future as the western line already serves Newmarket much better than it does the city. The area where huge growth will be is in trips to the city centre as currently the circuitous route is to slow. Even so, from west more still go to Britomart than Grafton and Newmarket combined.

        2. Au contraire!

          With the Auckland Uni selling up and moving their GI/Tamaki campus to the Brewery site across the road from Grafton Station, the numbers of people using Grafton will skyrocket.

        3. The time to Grafton theoretically won’t be any different to pre-CRL as although you will have to wait twice the average waiting time will be halved in each case. Of course people leave home in time to catch the next service which mucks up this argument a bit, and a transfer is still extra inconvenience.

        4. Greg yes they will probably increase, but nothing compared to what will happen with the city centre once you cut that travel time down dramatically.

          Hamish – Yes that is it. Even with solid growth, the best you could justify for a west to Grafton/Newmarket service would be a 15 minute frequency. By comparison with all services heading down the CRL then we could end up with 5 minute frequencies so much more convenient.

        5. I think it’s a pretty basic assessment in terms of frequency. If you want to split western service between the CRL and Grafton/Newmarket, you have to split the frequency. Basically if you send half the trains to the CRL and half to Grafton direct, the extra time it takes you to wait for a Grafton direct service is equal to the transfer time required if they all go the CRL.

          Connections between super frequent super simple service patterns is the way to go, folks in Auckland will get the hang of it just like they do in London, Paris, New York, Tokyo etc etc.

        6. Of course the really important bit is that the tracks are not being ripped up so, if in the future demand requires it, the services can be adjusted.

    3. The issue of Mt Roskill is an interesting one. I see the CRL as not a city centre project but one that is really about opening up the network across the whole region so in some ways it could be described as just a later stage of the overall CRL project due to it allowing for increased frequencies on the inner sections of the lines. Where it comes into its own compared to those other major projects is that it would not cost that much as the route is already established and designated. Just need to build the junction, grade separate New North Rd and then lay about 3.5km of double track along with two fairly cheap suburban stations. All up it would probably be in the $50-100m range compared to maybe $700m-$1b for the Airport and $2.5b for rail to the shore.

      You could also argue that Electrification to Pukekohe wasn’t as high on the agenda as the CRL but that is now being pushed up the rankings due to it the benefits it provides by doing it earlier. Further I would say that while Len campaigned on those three projects, campaigning is different to what happens when you get into office and deal with the rest of politics as well as having people looking at the issues more closely. Rail to the airport and shore ended up being pushed down the priority list a bit in the Auckland Plan.

  6. Matt. I suspect that it may be easier (and more useful?) to four-track Westfield – Otahuhu to allow your yellow service to push on to Otahuhu and terminate than it would be to create something at Panmure to termainate a train there and get it out of the way awaiting its next working.

    From a performance point of view, you have linked the two long routes together. It would probably give the network more robustness if the two long routes were linked to two short ones: say – Swanson/ Manukau, Mt Roskill / Pukekohe, Onehunga / Panmure (or Otahuhu)

    1. Yeah it is a debate as to whether the yellow line should go all the way to Otahuhu or not. While it might be physically cheaper you would also need to look at the extra cost of running the trains there and back again to help decide on the best option.

      As for you second comment, I agree and only put the image above up as an extension of the previous one. I have a whole heap of other patterns I put together as potentials if you were to include the Mt Roskill spur including just what you describe. They don’t have labels and have slightly different colours but here they are

      1. Would it be easier to treat your Mt Roskill extension as a dual-branch green line, rather than a line on its own? Similar to London’s Central Line, which has two western branches to Ealing Broadway and Ruislip. In that case, you’d illustrate the topology with a simple modification of diagram 2 to include a small green “tick” extension to Mt Roskill. Some percentage of west-bound green line trains would terminate at Mt Roskill, while the rest would terminate at Swanson. The percentage would depend on demand and on the number of trains per hour needed to form a useful service. Surely this would be easier to schedule than your diagram 3, where the yellow line is a mix of green and red line.

        I like the idea of dual-branch rail lines. I think it is a natural thing to do at the end of lines where the passenger density goes down and the physical distance between the terminating stations on different lines becomes greater. It sort of fills in the geographical gaps, while still concentrating trains and passengers in to the CBD stations.

        1. In this case the lines would diverge at Britomart too with one heading east and one heading south so I do think they are separate lines rather than a branch of a single line.

        2. The beauty of these arrangements is that every single line from every station goes as directly as possible to the CRL stations, which will easily have the greatest demand for travel at any time of day or night, barring something like an event at a stadium (the lines through Newmarket can go either way as it is about the same time and distance. Nothing ends up going “the long way round”.

          A further beauty is that on the isthmus each of the three corridors has a double up of lines, leading to a double up of frequency where the peak loading points are. From any of those isthmus stations both lines passing a station go directly along the same route to the CRL, but on the far side one line each goes to the other two corridors, meaning you can simply just hop on whatever the next train is to get to the City Centre or to connect to other lines, or you can wait for one particular service to make a direct crosstown trip to either corridor.

          It’s quite efficient and effective at the same time.

        3. The various operating patterns have their advantages and disadvantages. For mine though, the most important thing is for AT to start making these pattern concepts public. When they start taking about how the CRL will actually be used, it will surely make the project seem a lot less abstract, more real and a lot more relevant to the average person. This can only help to build support for it.

          Where is AT on this?

        4. Yes Glen I completely agree and that was one of the themes of the post. It is key that AT start actually talking about this kind of stuff so that people can start to see how the project will affect them.

      2. A big advantage of #1 in the list of 6 diagrams is that the blue Onehunga / Panmure service acts as an ‘inner’ for the southern and eastern routes. Setting aside platform lengths on the Onehunga branch, you could alleviate crowding by runing it as a six-car service in the peak rather than run 6-cars in all the way from Pukekohe when three of the vehicles are only needed inwards of Otahuhu.

    2. Linking the Western and Southern makes intuitive sense because they’re the bulk of the rail network and invariably will probably be the busiest line so you can end up with reasonably well balanced patronage. The Southern Line will probably have better numbers at its southern end than the Western at its western end which does leave open the possibility of thinking of the Mt Roskill branch as just a branch off the western line. But I quite like it doing something a bit different to what most western line train do so that you have options.

      The exact routings will probably be further refined over time of course. Great that we have an east facing connection locked into the designation so that we at least have all these options.

  7. I think the importance of Grafton has been underestimated. In my experiences, the train empties at Grafton in am peak and arrives relatively empty in pm peak and fills up at grafton. It serves 3 large education centres and, even as a public transport enthusiast myself, I find the idea of having to transfer at newtown to travel one further stop repulsive

    1. Sam, to keep good frequency and a regular legible service each line can only go one way. Would you rather the western ran past Grafton to Newmarket and everyone going to Newton, K Rd, Aotea and Britomart had to transfer, or if it ran down the CRL and people going to Grafton or Newmarket had to transfer?

      In any case the act of transferring will be simple: walk across the platform and wait around 2.5 minutes… but it is still a minor inconvenience for sure, so it makes sense to inconvenience the minority going to Grafton and Newmarket and favour the majority going to the CBD.

      1. There is also significant overlap between Grafton and Newton. Ie for the hospital only a extra 200m walking from Newton as from Grafton, so most people will just walk from there. Same with anywhere east of Grafton, it is actually only 700m walk between the two stations. I suspect Grafton patronage will noticably drop post CRL however commuters will just use a different station.

        1. Not so sure Luke, the schools drive a lot of Grafton’s current numbers and in the longer term the university site will also drive it up.

          The key thing to remember is that currently the western line is well connected to Grafton but the Southern and Eastern are not, under the options above the Western will involve a transfer at Newton [or a walk as you say] but in a situation where the frequency is so much higher and connections are without penalty…. so on balance a far greater level of connectivity that present. A 2.5 min wait for a connection is absolutely fine in my experience, it’s just that we have no culture of transferring yet in Auckland.

        2. “Ie for the hospital only a extra 200m walking from Newton as from Grafton,”
          Yes thats fine in theory, but what about when its raining, blowing or cold or any combination of them- most people wouldn’t be bothered with that extra walk.

          And while there may only be a shortish (indirect) extra walk from Newton Station to the Hospital, its across a noisy motorway bridge (or two – if you go via Symonds St and Grafton Bridge).

          Quite exposed, no cover possible, nor any pleasantness about it really – unlike the walk from GFrafton Station to the Hospital which is an uphill walk, but which has the Domain on one side with lots of nice trees to look at.

          We want PT to be the default “no brainer” option, not one where you have to grit your teeth and freeze your bits off doing it.
          Not if we want people to actually the stations willingly once they’re built, and not just put up with them, like some kind of “PT Cod Liver Oil”.

        3. I agree Greg, but in bad weather the Link to K’Rd station becomes a good option for western line travellers from the hospital…. Remember we’re going to become a ‘connections city’!

        4. Well those people will be able to transfer at Grafton to reduce their walk if they so wish. However really important to help out with those annoying cold walks in free transfers onto buses, and Grafton is well connected for that, or if you get off at Newton can bus to Grafton bridge then walk over.
          Grafton must also get a little bit of patronage from Khyber Pass Road west of the motorway, as Mt Eden is hidden down a back street.
          These people will certainly get an easier journey with Newton.
          Hopefully in conjunction with these new stations there will be some nice street rebuild projects, so streets, especially motorway overbridges. K Road shows what can be done, hardly notice that you walking over a 6 lane motorway.
          Totally agree that transfer will be no problems, especially with the station designs with island platforms, and it will make it very easy to head back towards Grafton and Newmarket.

        5. “Quite exposed, no cover possible”

          Uhm, have a look at Grafton Bridge and Park Road. Walking cover and wind shelter is certainly possible, even on a Grafton Road route. Not saying that it will remove the downside of the longer walk, but its the distance more than the weather anyway.

        6. Remember if walking across Grafton Bridge from the Hospital then wandering down to K’Rd station undercover becomes an appealing option over going up to Newton,; more shops and other diversions…. good Transit provision also improves street life….

  8. Hard to beat No3:
    Mt Roskill/Onehunga
    Separates the two long lines, joins the two lower freq spurs.

    And Sam it’s pretty good for Grafton, high freq service, direct for the whole Southern [including a direct link to Middlemore Hosp.], City stations, and inner Eastern. One transfer away for the rest. I guess the only problem may be that not Grafton but Parnell might be a little underserved depending on the frequency possible on the Onehunga line. It would at least need a section of double track for passing. Of course ultimately this would become the the Mangere or Airport line, be double tracked and have higher frequencies…..

  9. Will the Onehunga branch line and the Mt Roskill “branch” line ever be able to be linked together to form a single line?
    I assume theres some rail corridor from Onehunga going towards Mt Roskill by the motorway, but the current plans seem to leave the link up bit out.

    Which is it safe to assume is because its a big expensive bit of work to build and/or needs lots of earthworks to make it so?

    And if these two were ever linked what would that mean here – some kind of rail loop from Onehunga through the CRL to Mt Roskill and on to Onehunga would be possible.
    But would it change anything for the better?

    Personally I’d like to see a large loop that linked the Onehunga line to Mt Roskill and then in turn linked Onehunga to Panmure via Westfield or whatever that area is.
    To form a large outer loop, which would have lots of touch points to the other lines meaning lots of useful ways for more folks to get across town, without needing to go via CRL in all cases.

    1. Not much of a fan of loops…anyway the cost of getting a reasonable grade from the Onehunga foreshore up to the Hillsborough ridge is unlikely to be justified by passenger services anytime soon. Cross town services certainly could be run pre-CRL, say something like Hendo-Man City via Grafton…?

    2. What you are talking about has been called the ‘Isthmus Loop’ and would require the full length of the Avondale to Southdown rail designation to be built along. The mount Roskill branch is part of this but the remaining sections would be at considerable expense. It may be built for freight assuming growth on the North Auckland Line, but that wouldn’t be for a very long time.

  10. I also think #3 gives a good pattern.
    Onehunga & Mt Roskil frequencies are probably well balanced.
    Operating both western & southern lines directly to Aotea probably gives the fastest, direct route for the highest proportion of passengers. This also gives a high frequency connection at Newton, and service from west to Grafton and Newmarket. Grafton remains well served.

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