It has been a while since we heard anything about progress on another of Auckland Council’s key rail projects: a rail link to Auckland Airport from Manukau and Onehunga. The agenda documents for Wednesday’s board meeting of Auckland Transport highlight that quite a lot of work has been going on behind the scenes over the past few months – analysing at a broad brush level which transport solutions are needed in this corner of Auckland in the short, medium and longer terms. The result is a fairly short, but quite informative report that is probably backed by a much larger study that will hopefully also be released to the public in the fairly near future.

The study made the following conclusions:

– Packages incorporating rail connections in the airport corridor will be the most effective in delivering the project objectives in the long term
– The Rail Loop package would provide the best network resilience and highest benefits, while the package associated with a rail connection to the South is the most economically efficient
– The rail options would be expensive compared to a package incorporating bus services operating mainly on the existing state highway network, however the latter option is likely to be much less effective in the long run
– However, the packages are not mutually exclusive and the way forward is likely to be a combination of more than one package, involving a progression between the different elements of the packages over the study period. For example, the
improved public transport services might initially be started using buses on the existing state highway network, with a rail connection to the South or North being added later, ultimately leading to the completion of the rail loop as demand continues to grow.

At first glance they seem to be a fairly logical set of conclusions. The ultimate goal is, of course, rail connections to the airport from both Manukau and Onehunga. Without both links the line can never really function as a proper southwest rail link, connecting people from all over Auckland to the employment hub of Auckland Airport (and its surrounds) as well as offering extremely time competitive trips from the Airport to the city, Newmarket and other important nodes.

But at the same time it’s also pretty clear that this is a project that can be staged, and it’s likely to be sensible to adopt such an approach. Just as I think Puhoi-Wellsford is a road that should be staged (starting with a Warkworth bypass and safety upgrades, then seeing what problem is left after they’re implemented) it makes logical sense to stage development of rail to and around the Airport. The first step is obviously running better bus connections in the area – aimed at people who work at the airport as much as those travelling between the airport and the city centre. It seems crazy there’s no regular bus link from Onehunga to the airport, for example.

While the full “rail loop” (why are we always so obsessed with loops?) will require further investigation to determine its exact alignment, a broad overview of what’s proposed (including station location) is outlined in the map below: Once again at first glance there seems to be some logic to both the alignment and the station location – although I imagine with the alignment there will be some changes, probably mostly to bring it closer to the state highways and therefore minimise the amount of property that needs to be acquired (and limit the damage to Mangere). What is quite clear from this map is the potential for the line to really revolutionise this part of Auckland, offering a really high-quality transport option into the industrial estate around Auckland Airport (as well as the airport itself), but also offering Mangere and Mangere Bridge high quality transport links to the rest of the city. Mangere would seem ripe for comprehensive redevelopment as a model transit-oriented development, for example.

In coming to the conclusion that what’s highlighted above is the best eventual transport solution for the area, the study looked a number of different options.

Package 1 – Rail loop. This would comprise rail links from the airport through the northern corridor and southern corridor (connecting to the existing passenger rail network at Puhinui and Onehunga), plus the common elements (state highway, arterial road and local transport improvements)

Package 2 – Light rail to north. This would comprise dedicated light rail link from the airport through the northern corridor to Onehunga (connecting to a light rail network running into the CBD or to a rail station at Onehunga), plus the common elements (state highway, arterial road and local transport improvements)

Package 3 – Busway to north or south. This would comprise dedicated busway from the airport through the northern and southern corridor connecting to the existing bus and rail networks through interchanges, plus state highway, arterial road, and local transport improvements.

Package 4 –Rail connection to the south. This would comprise a rail link from the airport through the southern corridor connecting to the existing passenger rail network, plus State highway, arterial road, and local transport improvements.

Package 5 –Rail connection to the north. This would comprise a rail link from the airport through the northern corridor connecting to the existing passenger rail network, plus State highway, arterial road, and local transport improvements.

Package 6 – Bus lanes on the motorway shoulder. This would comprise express bus services from the Airport through the northern
 corridor and southern corridor using motorway hard shoulders, plus state highway, arterial road, and local transport improvements.

Package 7 – Rail or dedicated busway through Otahuhu. This would comprise rail or busway links from the Airport through the eastern corridor, plus state highway, arterial road, and local transport improvements.

Each of the seven options were run through an initial assessment of their effectively at ‘tackling’ particular issues, and their alignment with broader goals, such as land-use change:  Once again I guess there are no real surprises here. The most comprehensive (and expensive) option would have the biggest effect. The ‘cop out’ option of shoulder bus lanes would have very little impact. The more detailed economic assessments of the different options highlight something of a correlation between the level of cost and the level of benefit, although a few of the busway options probably start to drop out here because they’re expensive, but don’t provide the extent of benefit to justify their high cost. No actual cost-benefit ratios are provided, which is quite interesting: After looking at the cost-effectiveness and qualitative assessment of the various options, the study made recommendations on each of them – narrowing things down to four options, which would serve as something of a staged approach, shifting over time from a bus-on-motorway solution to an eventual full rail connection from both the north and east: 
I had been somewhat worried that this study might end up somehow recommending a busway option. Now I have absolutely nothing against busways (bring on the Northwest Busway!) but if we’re fundamentally trying to achieve a “one seat ride at rapid transit quality” between the Airport and the City Centre, which is something I had always thought this project was about, then a busway simply isn’t going to cut the mustard. Where are you going to put it between downtown and Onehunga? In effect we already have half the line to the airport – it’s called the Onehunga Line, so it makes sense to utilise the existing infrastructure rather than duplicating it or having to compromise on a fundamental goal of the project.

Overall I am pretty satisfied with where things are at with this project. The next steps will look at more detailed alignments and integration with other transport modes, undertake a more detailed business case and comparisons with non-RTN options (which seems a bit weird as the route is a designated RTN in all the planning documents) and provide a way forward to the third stage, which should be preparation of designation documents so the route can finally be protected.

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  1. There are definitely some positives in the report but I wouldn’t be to concerned with the next stage doing a more in depth analysis of the non RTN type options, remember this was one of the big criticisms from the government of the CRL business case. The study already seems to have gone some way to justifying the need for a full RTN saying there will be enough demand by 2041 for 30-50 buses per hour through the area. The other good thing is the NZTA is involved so there should be much less complaining about the business case from the government.

  2. No mention of staging the rail line itself which is interesting. Assuming each of the nex stations should be designed for bus to rail transfers anyway then why not stage things in a linear fashion. E.g build the bit from onehunga to Mangere Bridge first and have buses shuttling there, then extend it to Mangere town etc. They could basically stage it in over ten years of slow but steady construction.

    Also I note the Southdown link has dropped off the radar, it would be good but expensive and not the priority, so I can see why it is on the back burner.

  3. I’m not aware of one, but is there a designated route from Onehunga to the Airport?
    At least the route from the Airport to papatoetoe/Manukau is mainly farmland.

    1. There is no designation John but the assumption is the rail line would fall mostly or entirely within the motorway/SH20A corridor, which would make it a lot easier.

      I think the line on the image above is only indicative of it running right alongside the motorway, they would be crazy to build it 50-100m away as the map actually shows.

      I do hope they plan for the airport station to right in the terminal building, the proposed extension of the international terminal and closure of the domestic terminal would be the obvious time to make this happen. A Brisbane style situation where the station is outside the airport on the other side of a carpark would be much inferior.

  4. If you were to stage could you potentially stage it as a single track first before building the second track when demand picks up? I know that Managere Bridge is future proofed for rail, but would the grade from Onehunga and Managare Bridge be suitable for rail? It seems awfully steep particularly at that Onehunga end, it is also extremely cramped at that end especially if you had to extend the Onehunga platform.

    1. Oh please, what’s with all the timidity?, build it all the way and properly, Key now wants the Commonwealth Games in 2022, clearly we need to get sorting the infrastructure now, CRL and Airport line essential.

      If big sporting events are the only things these politicians understand I’m happy as they provide deadlines that help getting good stuff done. And Com. games means more people by air at Mangere not more SUVs from Takapuna: so Airport Rail not cars across the harbour. Yay.

      1. The reality is that it will get staged anyway (you can’t just construct a whole line at once), so it’s a question of staging with benefits or staging with no benefits.

        1. Build one track first. Start building up patronage while you build the second line. That way you get the benefits quicker and help push the BCR up.

        2. The cost differences between 1 and 2 tracks would be pretty small as the big money goes on securing the alignment and doing the earthworks. Single track just makes life difficult for nearly no benefit.

        3. That would imply a single train only shuttling back and forth. Which probably means one train an hour, which isn’t going to be attractive for an airport service. Then it’ll have to slow down every time it comes to the construction workers laying the second set of rails. Plus you’d probably have to turn off the overhead power on a frequent basis so that construction workers could do things like rig the second set of power lines safely.

        4. Doing it that way would make for much higher labour costs, and probably higher materials costs due to inflation. Better to double-track in one go, and take advantage of the people and machinery already being in place.

          Plus, as obi points out, a single track imposes significant limitations on service frequency and that has serious effects on the viability of the line. Look at Onehunga, which is limited to half-hourly services by a combination of single-tracking and Britomart’s dead-end design.

        5. For staging I think it would be better to do it by station rather than by track, extending the Onehunga line to Mangere bridge first would allow for a station to be opened there and patronage built up until the next phase of getting the line to Mangere Town Centre was finished, once that stage is done then the station could be opened as the new terminus until the next stage could be finished etc. With EMU’s running half hourly on the Onehunga line it will lead about 10 minute turn arounds at each end, extending the line to Mangere Town Centre would allow the same frequencies without the need for any extra rolling stock so would be an ideal starting point.

        6. There are economies of scale in construction and in commissioning that need to be considered too, staging like this may be no saving at all. But regardless the vital first stage is route identification and protection, let’s get there and then get the professionals in to discuss how to proceed. Oh and shake down the great waster of monies to help fund this puppy.

  5. Just build it already. Don’t worry about doing it in stages as it just takes longer / costs more. The benefits will be there for generations to come. You can BCR the thing to death but I have yet to talk to someone who thinks it is a bad idea.

  6. buses on the motorway shoulders don’t do the same thing as rail, no intermediate stops so no pick-up set-down along the way, apples and oranges

    a segregated and combined busway & heavy freight (remember the airport is a developing industrial/commercial area) route could well prove to have higher economic benefits and high capacity buses on a five minute or less headway would provide greater opportunities to travel

    the forecast headway of 15 minutes in 2041 is not hugely frequent, what would it be in 2021? 30 minutes would be unlikely to be competitive with other modes (risk of missing train, therefore flight etc.)

    1. Rail, and PT use in general, is always under planned for by the authorities and experts in this town…. 2041?: 5 min frequencies is my guess. I know, let’s build it it and find out.

      Remember the big fact that NZTA et al try to pretend isn’t there: what you build has a huge role in shaping demand; construction is never neutral, just some causeless reaction to an existing but unfulfilled desire. No, only build roads and we’ll all have to find a way to use them, no matter how inefficient or impoverishing this is. Build the CRL and the awareness and use of the whole network will jump, and there is so much spare capacity in the existing lines that this is a wise thing to do; get the latent value out of the existing ROW.

      And this route is such a no brainer. And extend the Manukau Line to Botany too, FFS.

    2. A busway is considered in option 3 but the problem is you either need to force everyone to transfer to a train at Onehunga or build the busway all the way to town which would be very expensive. The study indicates that by 2041 there will need to be about 50 buses per hour to service the airport at peak times and that doesn’t even seem to take into account the patronage from the other areas the route would pass through like Mangere. At those sorts of frequencies I don’t think you would also want to be mixing in trucks as well.

      I agree that 15 minute frequencies isn’t great and suspect that when the airport patronage is combined with the other stops along the line we would actually see 5-10 minute frequencies be more of a reality.

  7. The junction with the Southern Line looks less than ideal. I think if it were done properly the two lines would cross at right angles at different grades, with a station at the junction allowing people to change lines. Instead, the maps seem to show the lines merging and separating, all presumably done at-grade. That’ll limit the frequency of trains in and around the junction which will be hard to fix later on.

    I wonder what they’ll do at the Manukau end of the line. At the moment the line ends short of the center. To be really useful as a way of getting workers to their jobs at the airport, it needs to carry on through the center and out the other side to places the workers are likely to live. I’m assuming that a fair percentage of airport workers live in South Auckland, rather than further away.

    1. Re Manukau, I think the balance of the city centre will shift west towards the station, remember a branch of MIT is to be built right there, and there has to be room for the bus interchange station…..

      What will happen then? Continue the thing under SH1 and along Te Irirangi Dr to Botany Town Centre…. properly join the severed parts of South Side. You’ll have seen Nick Reid’s genius route:

  8. Remember this is just an indicative route, the exact route along with things addressing the junctions etc should be part of the next phase which is to work out the exact location and do a business case.

    1. A really important thing to consider is the role this route would have in reconnecting Mangere Bridge to Mangere Town Centre and them both to Manukau City… while the airport traffic, both workers and travelers, will form the backbone of this service and make it a clear winner immediately, those local connections will do a great deal to help fix a region severely split by motorways. Mangere Town Centre is hardly any kind of centre isolated as it is from its catchment by three highways…. this route, especially if it is west side of SH20 from Mangere Bridge then cuts over to the Town Centre side later has real local value. It’s not just about German backpackers or downtown suits.

      And Manukau City has failed to live up to the ‘centre’ status it should because it too is only served, and therefore also separated, by roads. SH1 is a big barrier to its easterly catchment, as is the railline and SH20 to the west. This connection, especially when it also heads east would facilitate some real functionality for this potential southern centre.

    1. Which makes complete sense, provided that there’s a third (and forth, in the future) track. Linking the airport and Airport Oaks to POAL’s inland port by rail is a no-brainer, but you can’t run rail freight on a high-frequency passenger line.

    2. One use they haven’t considered is having it as the primary path for intercity trains. It would make a lot of sense to have services too and from Hamilton, Tauranga etc stop at the airport… Although perhaps that’s a little too far thinking for them.

      1. Would require some pretty significant extension of electrification to make it worthwhile, since the current diesel passenger fleet is ageing rapidly and unlikely to be replaced. Plus they’re slow, noisy and very nasty compared to electrics, which is in no way a draw card for international visitors who’ll be used to near-silent high-speed trains, or for commuters.

        I can see electrification being extended to Hamilton with minimal fuss (and consider it a logical course of action, in any case), given that NIMT’s electrified section starts in Frankton and Auckland’s electrified metro section will end at Papakura (when’s Pukekohe getting the buzz?), but building it out to Tauranga is a whole different story.

        1. Electrifcation is hardly necessary Matt, many cities across Europe run an all diesel regional fleet and even the likes of Paris still see locomotive hauled carriages, albeit modern nice ones. A fine example would be Melbourne’s fleet of new 160km/h DMUs travelling up to 3.5 hours away. Heck even the three silver ferns could service the routes in a quite fast and comfortable fashion.

        2. Sorry Nick R, maybe Eastern European countries and Australia run all Diesel Rail Fleets, but I cannot think of any Train Networks in Western Europe save small lightly used Branch lines. Most Lines out of Paris about 80% are electrified. Hell not even the UK runs all Diesel Railfleets and the UK is Electrifying the GWR out to Cardiff.

        3. Yes Michael I was talking primarily about Eastern Europe, but Ireland is one example in Western Europe. More importantly there are many smaller cities across England, France, Germany, Spain, Italy that have only diesel service, even if those countries main intercity links are electrified. In comparison Auckland and the upper north island are very much in the same league as the minor centres, not Paris or London.

          Like Matt L says below $1 billion to electrify to Tauranga is fairly infeasible. The opportunity cost of one billion bucks is about $164,000 a day at a 6% discount rate. We’d have to be moving a hell of a lot of passenger trains on the corridor for the savings of electrification to offset $164,000 a day.

        4. Kiwirail looked into the costs extending electrification, I believe they got an external consultant to do the work and it was determined that there was little point in doing so unless they went and put wires up all the way to Tauranga but would push the cost up over $1b so meant it wasn’t feasible.

  9. Nick R – that is quite advanced! I think Britomart’s terminal platforms would need to be cleared, first and foremost.

    I think the junction near Wiri should be grade separated to allow all trains to go all directions. You would hope Papakura to Manukau would be done and g-sep by then. We’d then need Airport line to City and to Papakura.

    Maybe Western line trains could go via Onehunga and Airport to Papakura, and keep any non-Britomart trains off the main Southern lines. The new track would probably have much better line speeds and more spaced out stations, and so journeys might not be that much worse via the Airport.

    In terms of the Airport station, it should be a through station but with 4 platforms (2 islands) so some trains can terminate – such as regional ones or shuttles from Papakura, for example. It should also be partially in open air or in a trench (like Copenhagen Airport for example –,_Kastrup_Station ) so that regional diesel trains and potentially charters can sit there too. Maybe 5-6 platforms would give more flexibility – better build more at the beginning than underdeliver and have to go back.

  10. CM we are crap at planning ahead aren’t we? The vital thing is that the ‘metro’ platforms at the airport are integrated right into the arrivals and departure areas of all terminals. Regional lines as close as possible too. Freight, of course is a different matter.

    How likely is it that the Airport Company is at all interested in planning for this? How much of their income is from carparking? How forward looking can we expect them to be. Given AC owns a chunk of the business is there leverage- or is it all at arms length?

    1. I would say they are well into this and would probably contribute to a station. According to the latest results:

      In millions
      Airfield income $72.529
      Passenger services charge $78.760
      Terminal services charge $28.342
      Retail income $111.150
      Rental income $49.927
      Car park income $33.437
      Interest income $1.460
      Other income $22.118
      Total income $397.723

      So well under 10% of income is derived from carparking. They say in the results “Passenger Volumes are our biggest value drive”. So presumably anything that gets more passengers to the airport works for them. I suspect they offer carparking as there is no other cheap timely way to get to the airport presently- catching a taxi can wind up costing more than your airfare in many cases- and would happily convert the outer carparking into warehouses if they could to add to their rental income. Certainly Air NZ added carparking to its offerings after feedback from customers about the cost of getting to the airport and the cost of long term parking at the time.

        1. Nice work Governator, ta. you’d hope they could see the land saving and growth facilitating up side to well integrated and efficient PT to their business…..

        2. One assumes that they’re perfectly aware of it, what with it being abundantly clear from their annual returns just how low the per-square metre returns are for parking vs industrial/commercial land use, but haven’t seen any point in pushing for it when there’s been no support from government at any level.
          It was only in the last term of the last Labour government that public transport spending really gained traction, and the current lot are so vehemently anti that it’s amazing AIAL have expressed even this much support for extending rail in the airport’s direction.

          I don’t think AIAL have been given a very fair stick in here regarding their views on transportation. All they want is to get people and freight to the airport with minimal possible delays, but the historic environment has been all about building roads. So of course they were going to encourage the widest, highest-speed possible roads to be constructed. Doesn’t mean they’re anti-public transport, it just makes them pragmatic about the political environment. It’s much more effort to agitate for change than to agitate for the most-advantageous outcomes within the current order.

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