This post was first published by Nicolas Reid on his Linked In page.
The Onehunga branch was Auckland’s first railway line, running from the port of Onehunga on the Manukau harbour to the port of Auckland on the Waitemata. Despite being primarily a freight link for steamers coming up the west coast and the Waikato river, it had a long history of carrying people until the last passenger service ran in 1973.
It was reopened in 2010 as part of Project DART, following a package of work driven by Auckland Regional Council chairman Mike Lee and supported by a grassroots campaign by the Campaign for Better Transport.
The branch was reopened for passengers very cheaply, a mere $21m with half going on trackwork and half going on buying land at the Onehunga terminus and building two new stations and a third platform where the branch joins the mainline at Penrose Station. Just ten years later these costs seem stupendously small.
But there is a reason for this, the project was a no-frills job that did little to change the old single track freight branch other that make it functional. Its an example of how you can get things done quickly easily if you don’t load up the brief, but unfortunately that does mean the Onehunga Branch is severely limited looking into the future.
Limitations of the Onehunga Branch
In its current form the branch line can only accommodate half-sized trains running at best once every half hour, while every other station in Auckland can handle six-carriage trains every ten minutes at least.
The main things holding back better services on the branch are:
- Single track line. There’s only one track, which means only one train at a time on the whole length of the branch. Each train has to run all the way from the main line through the Penrose third platform, Te Papapa and Onehunga stations then turn around and come back the same way again, before the next train can enter the branch. This is the main reason why they can’t run more than 30-minute headways.
- Single track ‘wrong way’ junction. The junction is very basic. The Onehunga track comes off the northbound mainline track all the way up by the Great South Road overbridge. This means that outbound trains heading to Onehunga have to cross over and go the wrong way on the mainline for a couple hundred metres to get to the branch. This isn’t a problem itself but it does require blocking the southern line in both directions to give the Onehunga the green signal through. This is an issue with reliability and makes running more frequency difficult.
- Single track terminus. Only one track at the terminus means only one train at a time can stop there. Sounds obvious, but it means you can’t have a schedule where a second train arrives before the first has left, which makes it more or less impossible to do timekeeping/layover stops at the terminus at any kind of frequency.
- Level crossings. The 3.6km long branch has eight level crossings, one every 4 or 500m on average. Increasing train frequency would mean the barrier arms go down more often, which means more delays for pedestrians and road traffic. But that could also delay trains, as once the arms go back up, they have to stay up for a reasonable amount of time to let people and cars cross the tracks safety. This makes doing anything clever with single track scheduling difficult.
- Short platforms and tight curves. The platforms are only long enough for three-car trains, and the one at Onehunga can’t be lengthened because it sits hard up against a tight curve lined with apartment buildings.
- Third platform at Penrose. The branch line platform at Penrose is located quite far away from the main Penrose station, and connecting to trains on the southern line requires a 250m walk up and over the switchback footbridges.
So to summarise, Onehunga is stuck with what it has. The single-track line limits the branch to infrequent headways, and the single-track terminus and the junction at Penrose would still limit the frequency and reliability even if you could run more trains through the middle. The level crossings could become a problem if you did find a way to do more frequency, while the constrained platforms mean only short trains can stop there.
What are the opportunities and limitations for improvements?
The airport rail and CRL projects have looked at options for fixing these issues, but the main problem is to run “normal” frequencies and trains requires masses of work to fix all the problems at the same time. To run six-car trains to Onehunga (or the airport or another extension) would require a new Junction at Penrose, rebuilding Penrose and Te Papapa stations, double tracking the whole route, removing the level crossings and relocating and rebuilding Onehunga station. In effect, it could need a billion-dollar elevated rail viaduct and junction, or an even more expensive trench to bring it up to scratch.
This is obviously a hard thing to justify for two stations that currently generate one to two thousand trips per day at best. But a bigger conundrum comes when you want to run Onehunga as part of an integrated network, especially once the CRL is open. The CRL tunnel works as the central core of a through-routed network. If all the other branches of network are running six, eight or more trains an hour, how exactly do you handle one branch that can only manage two trains an hour? What do you have to do to an otherwise efficient and legible train plan to fit that in? And can you still justify the potential reliability issues of the awkward junction to get them on and off the mainline, when they could delay Southern Line trains carrying a thousand people each at peak?
Then there are the short platforms. The two stations that are only served by the Onehunga Branch probably won’t ever need six car trains themselves as there’s enough capacity in the three-car units (especially if you could find more frequency at peak time). But what happens once those trains continue past Penrose onto the southern line and through the CRL? Can you justify using up the peak slots in the CRL for the little branch line trains, when they could be used for full sized trains on the main lines instead?
There are a range of solutions that have popped up for running the Onehunga Branch with the future CRL rail network. One is to split one of the main lines at Penrose to run two trains an hour to Onehunga and the other six or so to somewhere else like Otahuhu. Another idea is to run those two short Onehunga trains an hour across town to Henderson, avoiding the CRL entirely. A third is to simply keep running the Onehunga line into Britomart to terminate there as it does today, while the other lines carry on through the CRL.
These are all technically viable options, but none of them actually provide any better service frequency or longer trains for Onehunga, and in some cases make connectivity worse. They’re sort of ‘damage control’ concepts, acknowledging that Onehunga branch line services won’t ever get better but at least trying to stop them making the rest of the network worse. Nonetheless, they all still end up running odd twice-an-hour services with short trains on the main line. This means still running these ‘low value’ services through multiple congested junctions and stations, taking up resources and space that might be better used for other trains.
The shuttle option
There is one other option, to run the Onehunga branch as a shuttle. I think this actually solves a lot of the problems and could be the basis for getting better service quality for Onehunga passengers without a lot of cost.
Under a shuttle arrangement the Onehunga line would effectively become its own separate short train network. Trains would simply run the 3.6km route back and forth between Onehunga and Penrose only, taking six or seven minutes each way plus turnaround time at each end. This immediately deals with a couple of the issues. The trains would not pass through the Penrose junction at all, making the southern line work more efficiently. They wouldn’t run onto the main line at all, so they wouldn’t use up space on the network, making the use of three-car trains a non-issue. The very short shuttle service would also be more reliable, itself no longer being exposed to delays at various stations and junctions along the line. This should reduce the time required for timekeeping stops at the terminus.
It would also make the service delivery much more efficient. Right now, running the Onehunga trains to Britomart takes two or three trains in service simultaneously (depending on the time of day and the stopping pattern) to keep the half hourly timetable. A short shuttle could do the same headway with only one train and crew in service. But perhaps more importantly, those existing two or three trains could run the branch every ten or fifteen minutes, doubling or tripling the capacity and slashing the wait time.
The downside of a shuttle course is that practically everyone from Onehunga would need to transfer at Penrose to get where they want to go. But that doesn’t have to be a downside if you can address the two things that can make transfers a hassle: the waiting time between connections, and the quality/convenience of the transfer environment. For the wait time, that is a factor of the service frequency of both the routes you are transferring between. Once the CRL is operational, or even before then, the main line side of the equation should be fine. With the southern line and probably also the western line running through Penrose Station there should be a train every five minutes or so each way at pretty much any time of day.
To me the question is: if we start from the assumption of separate shuttle service pattern for the Onehunga branch, does that let us significantly improve the frequency without breaking the bank, and what would we need to do at Penrose to make the transfer work well enough?
The following diagrams show the Auckland rail network with the width of the Onehunga line in proportion to the service frequency. The first one shows it as it is today, and the second what it could be with a shuttle.
What might an Onehunga shuttle look like, what would it need to succeed?
Doing some sums around the round trip and layover times, it looks like two trains shuttling back and forth on the existing tracks and platform could manage five trains an hour… if they had somewhere to pass near the middle. So this would allow a train every twelve minutes each way all day. Unfortunately, due to the time and distance it looks like a nice even 10 minute headway would require a third train (and some complex passing requirements), but a 12 minute headway is still far better than 30 minutes.
I’ve assumed that the trains wouldn’t dwell long at Onehunga, just long enough to let people on and off and for the driver to change ends. The main timekeeping point would be at the Penrose end, so effectively Penrose is the only terminus. This makes sense to do at the transfer point as the shuttles with an eight minute dwell time at Penrose could allow connections to perhaps four different trains across both directions at peak times.
If we are using two trains for the shuttle then there is no way of avoiding the need for double track section near the middle of the route for the two trains to pass each other. I say near the middle, but because of the longer dwell time at Penrose the halfway point on the schedule would be closer to the Penrose side.
From what I can see the easiest thing would be to extend the current second track siding that starts just east of the Mays Road level crossing and Te Papapa station, to just west of the O’Rourke Road level crossing. This is a 900m stretch of wide-ish corridor with only one level crossing to be doubled in between, and at Penrose the corridor is easily wide enough for two tracks on the approach to the station if not at the platform itself. In theory this should be quite cheap to duplicate as it requires no land and no major structures.
But what to do for connections at Penrose Station?
When the Onehunga Branch was reopened for passengers an extra platform was added to the side of the tracks near Penrose Station for the trains going to and from Onehunga, as the tracks actually bypass the main platforms. This is known as Penrose 3 and it is used in both directions. This was a cheap and pragmatic way to get access to Penrose from the Onehunga Branch, but the third platform is some distance away from the main station via a long up-and-over ramp and footbridge.
This means it’s not ideal for transfers between the two lines. It’s not terrible, it does meet accessibility standards and the path is pretty clear and direct, and currently very few people need to make this connection. But its not great either, and certainly less than ideal for a shuttle transfer. To use the current platforms to connect between an Onehunga shuttle and the main line would require everyone to walk about 250m up the ramp, over the bridge and down the other side, on a relatively narrow and exposed path.
I’m a little torn on this because it’s neither so poor that you wouldn’t use it for a connection, but nor is it quite good enough to say it’s ready to go. Perhaps some fairly simple improvements could make the difference, things like a canopy shelter over the footbridge like they have at Ellerslie, or possibly adding a pair of lifts or more direct stairs to supplement the long ramps?
What do you think?
So what do people think? Would the near-tripling of service frequency offset the somewhat difficult transfer between platforms at Penrose station, or would upgrades or a revised platform layout be necessary?
Is a reliable shuttle running every twelve minutes, with a connection to the double-frequent main lines at Penrose, a better use of the same resources than half-hourly but direct train to Britomart? I’m most interested to hear what current or prospective users of the Onehunga line think about these tradeoffs.
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Sorry, no pictures appear in the post. It will probably be because of my security settings, do you link to a site blocked by me? I have had this in previous posts but not lately.
It would be nice to have the photos…
The photos appear for me so it is probably a problem at your end.
I’ve uploaded the images directly so should work now
All good now thanks 🙂
Wait until the Save The Onehunga Branch Line Historical Society hears about you wanting it to have more capacity and better headways!
wait for the “save x service, no one will use PT otherwise!!!”
And then over the course of the next year ridership increases significantly, but no no, we dont care pesky stats or ridership numbers. Bring back the xyz!.
And by save x service, I mean save our one seat rides to Britomart, Newmarket, and Ellerslie. Britomart will become much less useful than Aotea say, soon enough too.
I think turning the Onehunga service into a shuttle is a good idea. I think there’s also scope for further amenity improvements over time:
– Upgrading Penrose station with better pedestrian access to the roads on either side, more covered waiting areas, better integration with the very good 66 cross-town bus route.
– Upgrading Onehunga train station to better integrate with the bus station (probably by moving the bus station to be next to the train station) so that transfers are easier and more legible.
– Level crossing removals (but only after removing all the level crossings from the Southern and Western lines).
The reasons why these improvements are a good idea include:
– Onehunga is a growth area with a lot of new apartments being built and scope for further intensification.
– Penrose and the adjacent stations provide access to the largest industrial area on the isthmus.
– Penrose is the main station for getting to and from Mt Smart Stadium (which is Auckland’s most sensibly located stadium).
– The new bus network relies on transfers and the Onehunga bus station is key to this but it’s hidden 300m away from the train station down a back street, hard to use and doesn’t have good amenities.
– Future transport links (CC2M or similar) will likely go past Onehunga station so it makes sense to turn this into more of a transit hub.
The problem is for such a short line people might simply not bother using the service at all.
This idea sounds the same as how weekend services on the Melling branch in Wellington were provided back in 1980 (similar length service, similar distance from the CBD). Within a few months the service was scrapped entirely.
From memory this is also how passenger services were provided in the last few years on the Onehunga branch before passenger services were scrapped entirely in the early 70’s.
This service exists in Cardiff for a shorter difference and is quite popular.
It’s an ex port line too.
https://en.m.wikipedia.org/wiki/Butetown_branch_line
Maybe look at the land with in the former Wye Junction, currently occupied by the Portacom business. I’d be surprised if that’s not still Kiwi rail lease.
Converting the line to light rail has its options as well, longer term, especially as it has a tighter curve radius, which might help at Penrose. It would require a complete track rebuild for ab underground power feed and most likely be standard gauge (4ft 8 1/2in).
If we’re going to run the NW Light Rail along SH20 then surely we could extend the Onehunga Branch down back along the existing corridor space down to Onehunga Harbour Road and have it run under the Light Rail alongside the motorway. Then instead of a weird station with a carpark hanging off it, the end of the branch is another rapid transit connection.
So then the light rail doesn’t need to run into Onehunga. Still need the existing station but it would need to be rearranged. Need to think how the buses would link in. Light rail to travel on the motorway bridge. There is a bus lane either side.
The long winding overbridges are off putting. Many don’t do it.
An underpass is short and safe.
We have underpasses at Ellerslie, Gi, and Parnell on the south line that work well.
I use the Onehunga line almost every day and would find the idea of a shuttle service very off putting – direct trains every half hour are a far more convenient and useable transport option than Having to transfer at Penrose twice every day. You may say the Penrose transfer is not terrible – but it is infuriating for passengers that that junction is so long and exposed and to be able to see trains on either platform departing without you when you have no way to get there any faster, in the massive crowd that has just got off a train and is going up that tiny ramp.
This change is probably going to be marginally less good for existing users, but far better for non-users. Higher frequencies are the best thing we can do to make PT more attractive.
I was sceptical, reflexively opposed even, but having read what you’ve proposed… it just makes sense.
That being said, I’d try and resolve the transfer problem by seeing if a third track could be run up to Ellerslie and having the train terminate there instead. The idea would be remodel Ellerslie so it’d have two platforms instead of an island. The Onehunga line trains would terminate on the western side of a island and north bound Southern Line trains on the Eastern side of it. Both platforms would be accessible by a slight rejigging of the current modes of access (i.e. bridge and underpass).
Of course, I have no idea if there’s room to run a third bit of track up. If there isn’t… in principle you could create a double door opening situation. Build a platform that runs from (3) to the northbound track… open the doors of the northbound trains on NIMT on both sides and ditto trains on (3). It wouldn’t make the the southbound transfer situations better but it would make the northbound ones into a flat journey. But, again, not sure about the possibility of this.
The point of this is a quick, mostly service-based change that could solve a few problems and greatly increase frequency with the same trainsets. I.e. its a cheap and short term option.
While something like running up to Ellerslie could be great, it wouldn’t solve the main problems of the awkward single track junction, running little trains on the mainline, and getting better frequency from two trains (you’d need at least a third in circulation to go as far as Ellerslie, or you’ve got less frequency). This would also introduce a new problem, being that you can’t terminate an Onehunga train at Ellerslie without blocking the main line for over ten minutes each time (they’ll need to get it, let passengers on and off, make a timekeeping stop then get out again the wrong way).
Sure all these problems could be solved by building third tracks and extra platforms and new junctions and new track switches and extra trainsets etc, but that’s probably hundreds of millions of dollars of capital investment to make it work. That is a whole lot of change for a two station branch line that moves a couple thousand people a day at best.
If we want more freight to go via rail instead of road a heavy rail connection between Southdown and Avondale needs to be resolved so as to avoid freight having to go via Newmarket. Once that is resolved then the form the network takes in that corridor can be determined. I favor a crosstown link between Avondale and Otahuhu.
Won’t happen. The western Line will be too busy during the day between Swanson and Avondale to put freight trains on while metro services are running so freight will wait till night to run through and at that time they might as well still use Newmarket which doesn’t cost any extra in infrastructure. This is especially so as building most of that route, even though already designated, will cause a massive fight with locals
If even a part of Ports of Auckland moves to Marsden Point, it is going to have to happen, it will be like the southern line now.
Or the equivalent of Metroport is located around Kumeu or Westgate.
If that is the case then Northport is not an option as it would be like making all heavy vehicles go via Queen St.
Disagree, it would be like making heavy vehicles go via spaghetti junction rather than the western ring route.
Going down queen street would be like going down CRL tunnels with freight.
Agreed, it wouldn’t help with scheduling.
If they used electric traction through the metro area for freight then there wouldn’t be any concerns with air quality either, and they would be a bit quicker.
They would have from say 9pm to 6am to run first with the semi-frequent urban services, and then a few hours of exclusive track time.
You can shift a lot of freight over a window like that. More than the northland line could for sure without significant upgrades.
Between westfield and papakura kiwirail manages to squeeze 10 or 11 outbound trains per day between subbies plus the same inbounds. so i dont see how avondale to swanson will be any more difficult
I guess because we want to increase frequency on the Western line from what we have now post-CRL, hence why the 3rd main is needed for that current freight traffic you note
They do this be restricting the length of the peak period where AT are able to run 10 min frequencies and by limiting off-peak frequencies to 20 mins. In addition to this they require AT to build extra time into a number of peak Eastern and Southern line services.
The peak is already longer on the Western line, although for some reason AT haven’t taken the opportunity to increase off-peak frequencies.
Between westfield and puhunui there is 12 subbies ph in the morning peak. (Same as post crl western line) and still a few metros depart or arrive and a couple of ex wgtn trains are scheduled plus te huia . 3rd main will make it easier but i disagree that its somehow impossible to run more NAL (western line) freight trains due to suburban train schedules post crl. Therefore avondale~southdown may happen.
The long term running pattern has 18tph between Avondale and Henderson, although only in the peak direction.
It might be possible to squeeze a few freight trains in but as we already see between Wiri and Westfield it requires timetable compromises for passenger trains.
ASL is going to be an expensive and controversial project, there is no way it is going to be built for the few freight trains that could be squeezed in between Western line services.
18tph?. Every 3 and a half minutes or so. Far out is this london is it? If they do get to those frequencies i would imagine it would only be for an hour or so and in the very long term. An hour or so gap in the morning and evening wont make that much difference to freight schedules running the other 22 hours of the day. And they can run counter peak direction during those two hours anyway. Im not saying a~s will be built. There is no freight need currently, but just saying suburban schedules post crl are not a good reason for it not to be built as was Matt L’s assertion.
While you are right it may only be a small peak, this also applies to the existing tracks between Avondale and Southdown via Newmarket.
If there is space to squeeze in freight between Swanson and Avondale there will be space to squeeze in freight via Newmarket.
There are no real scenarios where building ASL is viable.
Actually i take that back, i think the a~s line is an underrated opportunity for the suburban network. And therefore should be built. Crosstown light rail could be an option. However due to kiwirail already holding the designation, and potential freight connections i dont think it will be built as anything other than heavy rail.
The number of crossings (11+ in Onehunga) and the destruction of amenity along the Avondale-Southdown line, means it would be a very poor business case.
I don’t think you are allowed to use the word shuttle unless it is for the exclusive use of AT staff or people who live in Devonport. (Or AT staff who also live in Devonport).
We could make it an on demand shuttle. Book it in on the mobile app at any time of day, and you’re guaranteed a pick up from one of the three stations within the next 12 minutes, and no more than one stop on the way to get to your destination station.
Try to keep up. The AT Staff Shuttle ended years ago, prior to AT consolidating all staff into one building.
The Onehunga line was resisted by AT who wanted to operate a bus shuttle between Onehunga and Penrose, so a lot of the shortcomings can be put firmly at their door.
However, I’ve always thought that this short line would operate better as a simple shuttle, but not to Penrose but on to Ellerslie where a third platform could be easily fitted, or better a Newmarket three track two island concept, although to make that work best for the Onehunga branch would require the Onehunga shuttle to cross over the UP line, but if the cross over is close to the platforms that shouldn’t DDS1’s too much of a delay to the UP line.
If the Onehunga shuttle was to pull into a dual exit pair of platforms this would reduce the need for mobility challenged people from having to negotiate the overbridge and mean that passengers simply stepped off one train and walked across either platform and board the train going the direction they wanted.
With such a cross over this would give the ability for the trains to use the mainline to return to their depot, plus that centre line could be terminal line meaning that the UP and DOWN line platforms could be joined as one with the shuttle line in the centre.
The Onehunga branch is a perfectly adequate commuter railway providing a trip to town with a 30 minute frequency. Lots of suburbs would love to have something that convenient. It not much use if you want to go south on the rail network. I find catching two buses and changing at Mangere Town centre a better option to get me to Papatoetoe. It’s not that far to the buses and some stop at the station.
Would it be possible to run a separate line up to Ellerslie station. Would that help. What if trains could cross at platform 3 would that allow for improved frequencies. There is room to have another line and center platform at Onehunga. Of course I have always wanted to extend the track back down to the Port along the old formation there would be room for to two trains down there.
Just a question – how did the Onehunga line work, back in the day when we had a real railway system? Was it all one track back then, or is the single track a more modern / 1980s thing? They probably didn’t have long 9 car trains, but i suspect they had a better, more connected service? Where did it go to back then – did it also have the crossover problem at Penrose?
I am no expert, but I can think of a couple reasons.
No disability requirements or ownership of safety. You have a gaping maw between the platform and the carriage, this means the platform can be on any curve you want. Or really hardly any platform at all and people just step down.
The line used to run all the way down to onehunga wharf. There is more room for straight platforms down there.
Auckland’s only really had a real rail system since 2003, the ‘good old days’ don’t really exist for rail in Auckland like they do for Wellington.
Onehunga has never had two tracks and had never had a frequent all day service like it does now as far as I’m aware. It used to have a great tram service though.
Thanks Jezza. I was under the (perhaps mistaken?) impression that Auckland’s rail system worked well in the 50s and 60s? I think my Dad used to catch the train to Penrose in the 60s. Trains were certainly more common in Auckland back then – just not perhaps in Onehunga?
There were certainly multiple services per day, which would probably considered good service depending on what part of the country someone came from.
However, they were nowhere near the frequencies that have been run in the last 10 or so years. The rail network was typically carrying 3-4 million passengers per year during this period, nothing like the 20 million it carries now.
I used the Onehunga service in the last year of 70s operation. It consisted of a couple of wooden cars hauled by a Dsc loco. I think there were two morning services each way and two afternoon services each way. The services ran from Penrose and then the empty cars were attached to a scheduled northbound suburban service and taken to Auckland for servicing. There was no platform for the passengers who had to alight onto the ballast pretty much where the platform is now and either cross the main south line onto the Penrose station platform or use the overbridge.
Today the trains are smarter and there are more of them but the suggested shuttle link from P3 to the main station would be just as shite as it was almost fifty years ago. I think the idea to terminate at Ellerslie has merit
So five new EMU trains an hour to a transfer platform will be ‘just as shite’ as two old carriage trains a day that drop you on the ballast to walk across the tracks?
Back in the day the trains were pretty terrible to be honest, far worse than we have today.
I can’t find an actual timetable but according to Wikipedia, the Onehunga to Auckland route had 14 trains a day total (about one train every two hours each way) in the early 20th century, but when the Onehunga tram was opened in 1950 there was a significant drop in patronage and the train was cut back to run Onehunga-Penrose only. Not sure how that was run, a bit before my time! In 1973 they closed the passenger route entirely.
In 1937 the Onehunga passenger service was a peak-hours-only Penrose-Onehunga shuttle taking 7 minutes and stopping when required at Te Papapa, second class only except for the 0704 ex Onehunga:
* Mon-Sat mornings one train out (0740 ex Penrose), two trains in (0704 & 0812, the former through to Auckland Mon-Fri);
* Sat midday, two trains out (1144 & 1244), one train in (1203);
* Mon-Fri pm four trains out (1620-1752), three trains in (1631-1741).
Other suburban lines had an irregular service every hour or two (or so) Mon-Sat with peak extras, and a very limited service on Sundays.
“Just a question – how did the Onehunga line work, back in the day when we had a real railway system?”
It was used by freight trains from Penrose, to and from Onehungy Wharf
The transfer would put a lot of people off, having to get out at a desolate station and walk across multiple completely exposed walkways in the dark and rain, and wait yet again is far from ideal. It is bad enough to put people off.
Transferring from the Airport Shuttle to the train at Papatoetoe station is a similar experience, it’s an unpleasant, wet, and desolate station to transfer at and personally I wouldn’t do it once it’s dark.
How well did the Swanson-Waitakere shuttle that replaced the train there work out? Does anything bother to catch them?
Agree. For it to work some land needs to be purchased for platform 3 to be brought parallel with the other platforms and a high quality Newmarket like indoor transfer to be available.
Bringing platform 3 closer probably wouldn’t shorten the distance, as you still need the distance to get the height up and over. Look at the switchback ramp on Platform 1/2, at 95m it’s about the same length as the ramp from platform 3.
I think the biggest improvement would be a canopy like Ellerslie has, followed by a pair of lifts and maybe some stairs. That’s sort of thing would cost hundreds of thousands, but buying land and moving platforms and tracks would cost tens of millions.
Get the platforms in parallel. Install stairs and lifts as is standard on network. Not long ramps. Forced transfers need to be properly facilitated, or will be opposed and probably rightfully so. Make it easy as possible and this looks like the best option for the little line for the post CRL world.
“Transferring from the Airport Shuttle to the train at Papatoetoe station is a similar experience”
Try to keep up. Now you can use the AirportExpress electric bus to and from the Airport to Puhinui Station. Use the AT Journey Planner.
Try to keep up…
Puhinui Station is currently closed, not much chance of getting off a train there and connecting to a bus.
The AT Journey Planner is never updated for disruptions. In the past years this has for example meant that it is almost completely useless for any journey across the city centre. It tells you to go somewhere and then the bus you want to catch just doesn’t stop there.
You have to count at least half an hour of penalty if you have to connect to another bus in the city centre because of that.
So using the AT Journey Planner, that is really bad advice.
Great idea. Faster frequency etc. The insistence to only have a one seat trip is unrealistic in a more widely connected network anyway. Someone living in London, Paris or NYC wouldn’t bat an eyelid at having to transfer once in a journey.
The transfer really needs to be sorted. I had not thought about the Ellerslie solution, I think that would be best. But perhaps more expensive and they are being squeezed a bit by the constrained corridor at that place.
More cheaply, if you look on google maps, the 3rd penrose platform is not even near as close to the rest of the station as it could be. Purely so the disability ramp works, and therefore they would only need to build one ramp. No stairs or lift etc. Just shifting / extending the platform north, adding lifts and stairs would shave off most of the unreasonably long transfer. And adding covers to both platforms and transfer place would be needed. Just a decent station upgrade really.
I agree that running a shuttle option from Onehunga to Ellerslie would be much better solution than the Penrose proposal. More friendly access & better transfers for people. It only takes 9 minutes travel time.
Another possible solution to increasing the frequency is to install a passing loop…
The ideal location is halfway along the singe track section,… the Captain Spring reserve would be a likely place, there is space for potentially a 150 metre loop which could accommodate a 6 car set OK..
There is already a passing loop just North of Mays Rd which was installed as part of the Line upgrade. This is of adequate length for a three car unit.
Alternatively close Captain Springs and Church St crossings. Then the section between Alfred and Mays Road is almost 900m. This option would mean less property purchases, less crossings and no major crossing required on Urban Route 10 at Mays Road.
Closing captain springs seems obvious, given Mays Road is the main road in parallel already.
It all depends on implementation and on other circumstances. I remember I was walking on an industrial pipe stretched over dozen of rail tracks not designed for pedestrians at all to change from train to underground metro. It was not very comfortable, but I preferred that way because there was no other viable option for connection between two systems. Driving was not considered at all because it was taking twice more time.
What I’m trying to tell is that many commuters will choose any option even quite ugly if it’s notably faster than driving.
Speaking as someone who regularly goes Newmarket-Onehunga via train; no sale. I would give up altogether rather than change at Penrose.
Not even if the change was improved to The same level as Newmarket, and you had to wait an average of 2:30 for the connecting train? And your original train came almost 3 times as often.
Have to agree lets see if there are any relatively simple fixes that can squeeze a bit more frequency out of it. If it could get to a train every 20 minutes that would be great in my opinion.
A passing loop similar to the Johnsonville line would be the easiest way to increase frequency. A long walk over that bridge in the pouring rain to just miss the southern line train would be the easiest way to reduce ridership.
This is what’s wrong with Aucklanders. They want a hyper connected network but aren’t prepared to switch around the network. As I said above a New Yorker wouldn’t blink at having to switch lines. Single Seat everywhere is 20th Century and that type of attitude is what keeps people in cars. C’mon Daphne, you’ve got this
Some one who goes Onehunga to K Road area or Ormiston to Te Papapa is likely to vote the other way. Existing users shouldn’t get a veto on any changes.
“Existing users shouldn’t get a veto on any changes”.
Couldn’t agree more. Do we want to optimize for the good of people, or do we hand out veto rights like chubba chubs. Could be applied to so many things (zoning for example) and many others, but apparently that’s not what we do here.
I think your missing a key point that onehunga will become a key interchange station with the airport light rail and eventual connection with the western line, either through bus under the current proposed network or sometime of crosstown lightrail/avondale south down link and potentially could be one of the busiest stations on the whole network in a decade or two. There is also a massive opportunity to double track the onehunga line and integrate it with the western line, there’s even a illustration of it on the CRL website so I think its being planned and that would be amazing. Double tracking of the onehunga line was only projected at 650mill around 4 years ago so I’m not sure why you said a billion dollar affair. IMO the onehunga line should be double tracked integrated with the western, the avondale south down line built with a third main to New Lynn allowing a crosstown loop.
What you are describing is well into the future. None of what Nick is proposing precludes the Onehunga branch being double tracked and reconnected to the wider network in the future.
I’d go further than that and describe it as fantasy land stuff.
How is it fantasy land when the double tracking of the onehunga line has already been confirmed by AT under the ATAP and some type of long term link between onehunga and new lynn has been officially confirmed by AT under the proposed future network in the ATAP. My proposal is the only practical longterm one taking that into account and building the avondale south down link was costed at 1billion in a 2016 report I believe by kiwirail, so including a extension to newlynn based off third main construction costs and inflation etc could be done for 2-2.5billion. That’s a reasonable investment if we are serious about public transport and network practicality it would unlock, connecting the west to South (Mangere, favona etc )via train through onehunga. The only fantasty land is your vision, everything im saying is in line with official plans, people like you are why transport is bad in this country.
Nothing in ATAP for either Onehunga double tracking or a crosstown to New Lynn:
https://www.transport.govt.nz/assets/Uploads/Report/ATAP20212031.pdf
A line on an old map for decades in the future means nothing. It’s only when funding is committed that a project is confirmed, and even then it’s not certain. Aucklands history is littered with examples like this, but until the budget is there and the contract signed they’re fantasy.
At current construction cost escalation, $650m four years ago would be at least a billion by the time they’d finished doing it. Don’t forget that a project of that size would take five or six years to complete even if they started today.
No way, three years max considering thats how long the third main is taking and the CRL is taking roughly that per section. The 2016 paper also provided a method of construction that meant the onehunga line could remain open for most of the double tracking construction, onehunga has the potential to be a massive interchange and a shuttle just isn’t viable for that but its still well thought out by you.
The wouldn’t even have the business case finished in three years.
Onehunga a massive interchange? I think you mean Otahuhu, or Puhinui. Onehunga will become a busy LR stop, but not much of an interchange; anyone on LR and heading to city will likely stay on it, or already be on HR via Puhinui.
The Penrose junction and the finite number of CRL slots means it will never have sufficient frequency nor soon one-seat city destinations to be a viable change from LR for Mangere users, even if $1b were dropped on doubling and separating the line itself.
In any analysis precious CRL slots will go to main line services, as these will deliver way more value. The post above makes a compelling case for improved user value through higher frequency, though only also with a significantly improved physical transfer environment. Which looks entirely achievable and a significantly lower cost than all alternatives. Surely this is a more likely mis term outcome?
We know that the Onehunga to Britomart service is unreliable now, but this change would make things go from unreliably good as they are now to reliably bad with that overbridge crossing in its current form. Definitely fix that transfer at Penrose. Once I took a bus to Penrose to hop on the train and that road is deadly. Once I tried to ride my bike there. NO. Penrose station has no redeeming features, please reconsider.
My two cents is that it’d put me off using it ‘coz it changes the time equation too much. To get from town/Newmarket to Māngere Bridge, a one-seat train ride to Onehunga then a transfer onto the 309 or 38 is often the quickest way to do it. A 250m walk at Penrose and then a possible wait for a shuttle might be a deal-breaker; I’d possibly be better sticking with the 309. I ride an ebike most days now anyway, but the above scenario makes it a bit too much of a faff in my case. Dunno how it’d work for everyone else.
The difference is that to get from town/Newmarket, instead of waiting for the Onehunga Line (every 30 minutes, average wait 15 minutes), you’d be able to take any southern line train (every ten minutes, average wait five minutes), and transfer to the shuttle (every twelve minutes, average wait six minutes).
So on average you’re saving four minutes, but more importantly (for me at least) you can leave at any time and hardly have to wait.
That’s the trade off, do you give up an always-infrequent one seat trip for an always-frequent journey that requires a connection.
This is a fantastic idea, this makes the Onehunga so much easier for anything except the direct trips to Newmarket, Ellerslie, or Britomart (and not any worse for those, trading a transfer for a way more frequent service). But that transfer would be an absolute nightmare. The transfer can, thankfully, be easily made significantly better. See the image below (blue platform and light blue over bridge with elevators).
https://i.imgur.com/I3yt7U0.jpg
Try this link
My thoughts were, if you were going to spend some money, to make a new island platform 2/3 to the west of the existing. This would give you a cross platform interchange between the onehunga shuttle and the northbound southern line. Southbound southern you’d still have to go on the overbridge.
Like this (hope the link works), looks like this would fit within the rail corridor: https://media-exp1.licdn.com/dms/image/C562CAQE0zlvjIN9-TQ/comment-image-shrink_8192_1280/0/1620903329624?e=1621414800&v=beta&t=wmq_RVmHvxBXTTcKL28wCogi7rQiS7ne5sftcXmxcNQ
We’d need large elevators too train loads transferring. Not a small Sylvia Park size. More like Newmarket size.
If it is going to be trainloads, we should be going for escalators, not elevators. I’m seeing this as an interim option until the corridor is converted to LRT, once that happens , we definitely need escalators.
The only real thing lost is the express and therefore faster trips that the Onehunga line makes on the southern line.
Apart from that, average trip times would be less, if you include the average wait time of 15 minutes at onehunga station waiting for a 1/2 hourly service. Compared to a service every 12 minutes (6 min wait) and a transfer to a train every 5 minutes (2:30 min wait)
What if you can read and understand a timetable and arrive at the train station 1 minute before departure time?
Agree with you Zippo.
In Waiuku we have two morning buses an hour apart. We do not stand in the dark for half an hour waiting but turn up 5 minutes before.
This is where the lines get blurry. Regular trips differ from non regular trips. If I’ve decided I want to go to or from onehunga spontaneously in the weekend, I would likely sit at my house for 20 minutes doing stuff all and then leave home get there 5 minutes early to the station. So I’m less likely to go, more barrier, waiting around time to decide I don’t want to go. Or that stuff it, the car will be quicker if I leave now etc. clearly a worse transit experience.
However if I’m on my highly optimised commute to work then the half hourly service is less of an issue. But a massive pain in the ass if I make it there as the train leaves.
Given the terrible off peak ridership on the onehunga line, we can see the results.
Then you travel differently to most of the population for most of their trips. Most people get ready for their trip walk out their front door and walk/cycle/head to the transit stop/drive. They don’t specifically schedule their departures. Similarly for appointments or shift work, people can’t schedule travel around a schedule.
The only reason that a lot of people seem to do this is because our PT system is so bad that PT is *only* viable for the tiny minority of trips that can be scheduled around PT.
What if you don’t need to read a timetable at all, because it’s guaranteed that you’ll only have to wait a few minutes for your bus or train or transfer to arrive?
That’s how it works for me with the Northern Busway. Local buses are usually just out of sync with the citybound NX1/NX2, but those run every 10 minutes off-peak so the wait is not so bad.
During rush hour, when there’s a busway service every couple of minutes, I can step off my local bus, cross the platform, and step right onto the citybound bus – barely any wait, no need for a timetable.
Frequency is freedom, and will incentivize more people to use public transport.
The return trip is normally harder to time right too from another service when out and about. From home you can wait around & make use of the time easier. We have literally done this for going from Penrose on the Onehunga line but often mistime it and have to take a Southern line anyway.
Most people don’t actually have the ability to time their every minute around a train timetable.
For example, while my work hours are fairly regular I can’t guarantee I’m done to the minute any day. There might be a meeting, a phone call, a report due, a bump into someone on the street corner on the way to the station, etc.
Same when leaving home, did you need to put the bins out this morning, can the kid still not find their other shoe, did you spend a extra 90 seconds daydreaming while tidying the kitchen and now you have 29 minutes to wait for the train to be half an hour late for whatever you were trying to get to…
Same with using the train for a doctors appointment, or a movie, or whatever. Good transit is available when the user wants to travel, not the other way around!
Yes this is part of being reliable. If you leave 5 minutes late, will that balloon into arriving 30 minutes late?
(for the many of bus trips near me, yes, because all cross-town lines around me have a 30 minute headway)
If yes, why would you bother waiting maybe up to 30 minutes for a bus if you can drive there in 15? Not going to happen.
Plus, maybe you come from another bus, what if it is delayed? Now you have to wait 25 minutes at your station. Which—thanks to the magic of single use zoning and single use buildings—really means waiting. This unpredictability is a reason why public transport commutes are so soul-crushing.
You need to add a bit of time for the transfer to actually happen. A 250m walk with turns is probably a bit over 2 minutes. In practise this will mean you would get on the train to the city on average 4 1/2 minutes after the train from Onehunga stopped.
True, under such a shuttle scheme, it would be totally unacceptable to not upgrade the transfer at penrose, or run up to Ellerslie on a third track. So I’m presuming its a going to be a lot shorter than 250m. Wishful thinking perhaps.
But yes, probably another minute added for transfers.
Also
1) There is also the “sudden crowd” aspect of transferring train to train. If there are 240 people from Onehunga disembark at Penrose and they walk single file that is a 4 minute long queue or as an average a two minute queue. This is now 4 minutes to get from one train to another with waiting not counted.
2) Will this Sudden Crowd affect the Southern Line? I would suspect not but if the Southern Line was crowded for some reason people may not get the next train.
Of course some people will see the next Southern Train but not get there in time so there total wait will be greater than 10 minutes, which is a lot if compared to a 30 minute direct trip.
1) yes, this would have to be a design consideration. You would want to ensure you can handle full trains of people all at once walking between. Multiple, wide pathways. Or at least enough consideration to be able to build for that in the future.
2) If you consider the alternative. Continuing running 3 car trains to britomart. You are taking a potential 6 car (or eventually 9 car) slot away. So overall network capacity will be increased by running a shuttle and having larger southern line trains. If the southern line was filling up under this shuttle scenario, it would only be made much worse by putting in the Onehunga line as it stands today.
Yes these are the trade offs, 4 1/2 minutes is a touch slow for the transfer time, it would be more like 2 to 3 minutes but the point holds.
The trade off of the couple of minutes transfer time is having trains that depart every 12 minutes instead of every 30, so on average you’d save 9 minutes wait time each way… so probably still quicker on average.
I don’t think you will get the ‘sudden crowd’ effect because you wouldn’t have 240 people depart each train because they would be divided across five trains an hour instead of two.
Well you might get that problem if peak-hour patronage increased 250% but that would be unlikely, and a good problem to have!
One factor than makes Feeder and Trunk more attractive than point to point is if the trunk has high capacity “vehicles” that are not possible on the feeder portion. The increase in transfers makes Feeder and Trunk less attractive. So make the transfer easier and the balance overall is probably for the shuttle option.
The change in actual use would be the balance of an improved frequency from 30 to 12 minutes against the need to transfer. In one study transferring was the same as 8.5 minutes of extra travel. The 9 minute decrease in wait may not be enough to result in a better service for passengers. I note that there is probably not a large walk up at Onehunga meaning people will have to transfer twice to get from Britomart to home.
I would be looking at making a list of all of the possible improvements that could be done to increase the functionality of the service, including:
– Passing loops
– Trenching the rail service
– Closing level crossings
– Putting lifts an a new transfer route (raised or subway) at Penrose station
– Second track at Onehunga
I’m sure there are more, but it’s about creating a list of options that can be publicly viewed and discussed.
For prioritisation I’d look at what would exclude other items or require rebuilding later and doing those first, then some form of cost, so that cost benefit could be looked at.
We’d want to start improving things, then start making service changes, trying to take people on the journey of improvement, not making change and then justifying things.
There’s already been studies into double-tracking & grade-separating the Onehunga Line, in 2016. Costs were estimated at $500 million (which didn’t seem to include a grade-separate junction at Penrose).
https://at.govt.nz/media/1927314/draft-smart-indicative-business-case-appendix-h.pdf
The Alamein Line is run largely as a shuttle in Melbourne with a change at Camberwell. It’s double tracked virtually all the way, it always seems very quiet to me. Even pre covid
The biggest impediment to increased train frequency is surely the level crossings, either left as they are ,or 2 years of disruption as they are undergrounded.Given the current antipathy to LTN in Onehunga, will take a good PR campaign, just don’t mention cycle in it or you’ll have no show
Am I right that if you did the Onehunga_ Ellerslie option you would need its own line for shuttle for 3km running next to the mainline? When it gets to Ellerslie would it just disembark/board leave or would it sit? The it heads back on its own line to Onehunga. It seems a lot of line resource for a shuttle, The frequency with two trains would be less than 12 minutes Also the previously proposed cross over point would have to move closer to Penrose. Neither deal brakers but all points to consider
its more like 1.5km from Penrose to Ellerslie. I also have no idea what the grade separations look like, is there enough room for a 3rd track under Great south road? etc
I suspect Ellerslie would be a drop and go type deal.
Given that the line would have around 10 movements per hour, it would still be one of the busier pieces of line in the country. Compared to the >300 million spent on the northland line which might have a couple per day now. different situation, but still.
They had to shrink the platform width at Ellerslie about 10 years ago to fit an extra motorway lane in so I doubt there is room for an additional platform and track in the rail corridor.
Interesting. If they were willing to make a retaining wall then I think they might have enough room for another track. But seems too cramped for a platform too.
https://goo.gl/maps/51dnku6uFF5CFBVp8
Slightly further south down the platform there’s more room, although that would pose issues too with connectivity.
This little carpark could be purchased maybe.
https://goo.gl/maps/uoAb19evMhFefHiQ6
Its a shame Ellerslie doesn’t have more room. It could be a big hub.
Maybe those buildings altogether could be purchased, hub upgraded, and sold on to develop into mixed use apartments / shops type deal. A Panuku job
Ellerslie had plenty of room once but it has all been taken by the motorway.
Makes sense. Trading a one-seat ride for frequency. Could be the start of a west-bound LRT service to Avondale, eventually?
Clearly, from the comments above, the transfer station is an issue so that would need work. Ellerslie termination sounds interesting, especially as an interchange to the eastern busway and eastern line.
I have always wondered
That’s a great point. If we could make a better interchange with the one of the busiest bus routes in the city, the 70 (and make the 70 better), even by just bringing the bus stops closer to the motorway footbridge then this would continue to be a nice little hub. Except now with much better service to Onehunga, so it would be a feasible trip. Instead of a half hourly service, equivalent to some small feeder service but on rails.
The extension of the service to Ellerslie would be a very valuable upgrade compared to the pure shuttle to Penrose.
Alternatively, could it be possible to elevate light rail above the existing Penrose heavy rail platforms (something like the long-term plan for Puhinui Interchange), and extend light rail from Penrose to Sylvia Park or Panmure? That would solve the transfer dilemma and improve connections with the eastern line & eastern busway too.
I’m still inclined towards converting the Onehunga Line to light rail concurrent with CC2M, and extending light rail from Mt Roskill to Avondale to operate Harriet Gale’s Crosstown Light Rail proposal from 2018.
That would:
1. Negate the need for the Henderson-Newmarket-Otahuhu ‘Purple Line’, enabling the highest possible frequencies on heavy rail to Swanson, Pukekohe, and Manukau.
2. Fill the New Lynn-Onehunga section of the proposed RTN.
3. Create the potential to extend light rail east from Penrose to Sylvia Park or Panmure? Especially if the Eastern Busway and A2B get converted to light rail in the long-term.
4. Allow for interim Penrose-Airport light rail service, in the event that CC2M is built in stages.
The issue with the Onehunga line shows up when ever there is an issue with the Southern line etc at peak with it getting run as a shuttle until the timetable comes perfect again.
Yes I think it would be better as a permanent shuttle though it’s nice the limited stops service cruising alongside & faster than all the motorway traffic often.
As mentioned by the posts author and comments made the Penrose station transfer need to be greatly improved. The shelter for starters would be good, a reconfigured overbridge & lifts as per Sailor Boy sounds better.
Another helpful thing would be large displays showing either Southern or Onehunga times that you can read from either Station or Great South Rd bus stations/P&R before committing to which platform you make your way to. I’ve often arrived thinking which train may turn up next but don’t have time to look on an app (or have and then narrowly missed a service, other people don’t always have an app or data to do that even).
Breaking News: well it is Onehunga related.
https://www.newshub.co.nz/home/new-zealand/2021/05/onehunga-low-traffic-area-vandalist-removes-temporary-roadblocks-part-of-decried-safety-programme.html
People are just scum aren’t they. Surely someone has got some crystal clear footage of this clown on their forklift?
The ones that are scum, are the ones that spent $41,000 on those crates.
What an appalling waste of money.
The plywood crates for Onehunga had cost around $41,000 to be produced, transported and installed – NZ Herald.
Yet more absolute lies from the NZ Herald then, no surprises there.
Immovable bollards and some trees might have been better. . .
Great idea. It literally improves all services on the network including Onehunga with the only downside being the connection which as you point out can easily be improved with a pair of lifts and a bit more shelter (and I’d add more lighting & CCTV for safety).
Super geschriebener und informativer Artikel :-). In diesen Blog werde ich mich noch richtig einlesen
Erm, Danke!
I have seen a short line starting off a metro line exactly like this before.
Maybe I missed something but how did that platform end up being so far from the others? And while you still need a long switchback for accessibility but you can also build a set of stairs.
A very very low budget to open the branch line a decade ago, I imagine
Yes but there is no obvious reason why having the platform closer by would be more expensive.
There are already stairs down to Station Road, and there is room where those stairs go down.
https://goo.gl/maps/SwE8XmhK4ggtbGMb8
25kv feeder station in the way. Why it was put there, who knows. Both projects were done at the same time.
It was done like this because it was very cheap and it all fitted in the rail corridor without buying land or moving tracks.
Excluding the land for the station at Onehunga, they spent $10m doing the whole project, it was super cheap.
Electrification design started the year the work on the Onehunga platforms was finished, so they weren’t done at the same time. That substation would have been located there because the space was available.
Page 21 of the ATAP says the onehunga line will be upgraded to enable “longer and more frequent trains” which can only mean double tracking.
Just saw this – so maybe no one will come back to read my reply… 🙂
But as a daily Onehunga line user, I would be happy with this if the Penrose connection is improved (as many have noted above).
The key point that has been mostly ignored in the original post however, is that there is a major wave of residential development happening in Onehunga, as well as Oranga, and Te Papapa. And it is likely (if not certain) that in the next 20 years a significant amount of the light industrial land use in the area will also be converted residential.
And with the Light Rail passing through, and the possibilities allowed by the Onehunga to New Lynn corridor, there are opportunities and considerations not fully addressed in the OP.
A shuttle may still be the best option, but we need to really extend our vision beyond current circumstances, and (unlike most Auckland Transport planning) really think about the longer term.
We’ve seen from Covid, and the Government’s resulting desire to use infrastructure to stimulate long term economic activity, that freeing up large amounts of money is possible for the right uses.
We may look back in 20 years and think 1 billion to double-track the line would’ve been a prudent investment…?
Just too soon to spend that much. There is lots of development going on elsewhere in the city too.
Would be nice double tracked etc
The disadvantage to building huge capacity early is that you don’t use that capacity for decades. But you still have to maintain a larger, more expensive asset, the money could have been working and doing good if we had invested in other projects so there’s big opportunity cost. Plus there is the risk that politics or other changes happen which means the asset will never get to be used to capacity. Representing wasted money.
However you are correct, we might look back and think that was a good move. Maybe not though. Its hard to tell if we invested the same dollars in other projects we might have had a better end outcome. EG northwest rapid transit
Jack, surely that sort of approach is a recipe for never doing anything within the Public transport area.
At some point a bold move in building a particular project will encourage the patronage that will in turn show up other projects that will enhance the bold move of before.
Cool, thanks for the replies.
As mentioned, I’d be more than happy with a Shuttle – if the Penrose end is improved…
If you look at the space in that big yard at onehunga, there’s quite a lot of space there. If they were to just change the location of the platform so that it fits longer in the yard, then the 6 car train option would work. There is enough space along the line for 2 tracks, apart from the tight area into onehunga train station. But if they bought some land off the factory owners to the right of the tracks, it would work. Also, if they changed the location of the platform at onehunga, they could have an entrance at Neilson street and at onehunga mall. It would work well.
There is already a passing loop just North of Mays Rd which was installed as part of the Line upgrade. This is of adequate length for a three car unit.
Dave Field, that loop on the Onehunga Line just East of Te Papapa is not a proper crossing-loop and has never been used as one. It is designated as a siding and to my knowledge it is not electrified. That is not to say it can’t be made into a proper loop, though it wouldn’t be ideal having a crossing-point so close to a station but not actually at the station. Much better if the two were co-located. But it is what it is, and it could be used for crossings if the will was there. Wellington’s Johnsonville line supports a 15 minute frequency on a single track branch with 3 crossing-points.
Anyway, in the 12 years that the Onehunga branch has been operating, I don’t think any thought has been given to upgrading it to allow higher frequencies. Everybody seems to blandly accept that the skeleton-service it has now is all it will ever have, unless the whole thing is double-tracked and several road-crossings are somehow eliminated.