As the CBD Rail Tunnel project slowly inches towards potentially becoming a reality, as a good public transport dreamer I feel that it is my task to look beyond this project to see what longer-term future projects might be needed to ensure that Auckland’s central city has the ability to cope with possible future railway lines that may feed into it – including a North Shore Line, a “Far East Auckland” Line (that I generally refer to as the Howick/Botany Line), an airport line and so forth.
Assuming that the rail tunnel between Mt Eden and Britomart gets constructed, then I would guess that we would generally end up running the following two main service patterns:
The Green Line effectively links together the Western Line and the Southern Line, via what could be called the inner city “loop”. This would enable someone to theoretically catch a one-seat ride from New Lynn to Papatoetoe via the loop. The Blue Line links together the Eastern Line with what would initially be the Onehunga Branch Line, but would hopefully eventually be extended to the Airport. Some diesel services from Pukekohe and Huapai would probably still terminate at Britomart and obviously avoid the tunnel – allowing direct access from the west to Newmarket and Grafton Stations on these services.
Now while this situation should very much suffice for our rail system in 2020-2025, when hopefully the tunnel and the airport line are newly built, what about in the longer term when we might want rail to the North Shore or rail out to Howick/Botany/Flat Bush? How would those additional lines fit into the mix? Could we really squeeze that much more out of a system that, even with the CBD tunnel, would still have some pretty significant bottlenecks at the east entrance to Britomart, at Newmarket, and the limits that a 2-track tunnel would bring (roughly 30 trains per hour in each direction I guess). Nick R did a guest post on the issue a while back, although I have a slightly different solution to his one.
My idea involves constructing the CBD rail tunnel as planned, and the first stage would end up with the situation shown in the map above. But for a second stage, the stage where we’re trying to provide a Howick/Botany Line and a North Shore Line within the constraints of the Britomart tunnel and the capacity of the CBD tunnel itself, I would look to solve that problem by completely bypassing the existing infrastructure with this later project – and creating a line that is completely independent of the current system – at least until it was well east of Britomart where it could end up sharing tracks with the eastern line (which would have hopefully been four-tracked by then). This additional line is shown in red in the map below:
This additional line would link together the North Shore Line and the Howick/Botany Line completely independently of Britomart or the CBD tunnel. I envisage there possibly being three stations – Gaunt Street at Tank Farm, Midtown (where transfers to the CBD tunnel could be made) and a refurbishment of the old Strand station – which could allow easy access to the development occurring in that area while at the same time could also potentially be where inter-city trains terminated: to help ensure Britomart doesn’t get overloaded.
With this system I think it would be possible to run trains at 5 minute frequencies on all three lines in both directions without many problems. That would equate to 24 trains per hour each way through the CBD rail tunnel and through the Britomart bottleneck: effectively enabling both Britomart and other stations on the CBD tunnel to be served by 48 trains per hour. This is probably about the limit before we start having serious problems. Which is where having our Red Line separate has its advantages, as it can add another 24 trains per hour of capacity into the CBD (12 from the north and 12 from the southeast) without affecting Britomart or the tunnel at all.
Of course this red line may not be constructed for another 30 years, and would be very expensive. But it does seem to be one of the most effective ways to add new lines to the system at a “second stage” of rail development – after both the CBD Tunnel and rail to the airport have been completed as the first stage. Critically, under this plan we don’t have to change anything about the CBD Tunnel project as it is being currently proposed – and don’t end up potentially putting it at risk over debates about whether Britomart should be bypassed or whether the tunnel should have four-tracks instead of two.
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Could you not include a uni station on the red line? Shouldn’t slow things down too much, and would be a prime station. I think it would be far better used than the Parnell station.
Matthew, the idea is that the Parnell station becomes a de-facto university station by having a pedestrian bridge over SH16 linking in to Alten Road. The university is inherently difficult to provide a railway station for because it is on a hill surrounded by valleys (Queen Street on one side, Grafton Gully on the other side). That means that any station would be hellishly deep to ensure our rail line didn’t pop above ground elsewhere.
That equals really really expensive.
Not necessarily so! Part of the reason the old Auckland Railway Station was relocated to Beach Road in the late 1920s was that it was intended that it would be connected to what is now the CBD via a tunnel (I think the first station would have been at Town Hall). As far as I can work out, the line would have crossed Beach Road via a rail bridge and entered a tunnel adjacent to the Station Hotel, so no real depth if they’d constructed a station in Albert Park, say. There’s absolutely no reason why the same couldn’t happen today as presumably they’d worked out all the grades, etc. Of course the scheme was dumped as part of a cost saving exercise by the provincial interests running the first National party administration leading to the station becoming a bit of a white elephant rather than part of an integrated transport solution.
That is possible Christopher, although a deep tunnel seems more feasible to ensure we get well under Queen Street and also to ensure that the red line can pass underneath the existing line that links Britomart and Newmarket.
Good point. I was being a bit dumb on Parnell – I was thinking of the Auckland train station. The Parnell Rise station would be a fair bit closer.
It looks to me to be a good mix of the rail infrastructure that would be in the city, I think it is a far superior (and cheaper) idea than what was rumbling around my head last week (and I posted today)…
To get diesel services stopping at a refurbished strand station would require them coming from the Eastern wouldn’t it..?
Why would terminating trains have to come from the Eastern line
@1, because of the junction… If you look at the map Admin has done, the green and red lines cross each other (presumably with the red line under the green line in the start of a tunnel) meaning trains using the Strand station would have to come from the Eastern Line…
You could design a suitable terminus in the ‘triangle’ betweeen the lines much how the old terminus worked, the main problem would be trying to do that and get a set of local platforms for each of the suburban lines plus maintain the connection into Britomart. It would end up the rail equivalent of spaghetti junction, probably need to have tracks on two levels.
But surely trains can come down the Parnell branch and then change tracks?
Purchasing the rail station back for refurbishment would have been ideal to do now, the leaky apartments in there were selling for 10-14,000 each. In the long term I can’t see this building ever becoming very valuable so it will hopefully remain something that could be re-converted to actual use as a train station in the future.
Jeremy, yes those trains would come from the east. It would be nice to restore a public use to that amazing building.
The North Shore line is probably the most problematic of all lines to fit in and at this stage I’m not convinced of any of the options I have seen (and I don’t have a good solution for it either). One of the issues with an alignment like this is all of the strata titles that would be needed as the route doesn’t stick to the roads. A bigger problem would be the building foundations that exist, especially for some of the towers along Queen St, they might not be so easy to avoid or may create huge costs for the project.
Is the current CBD tunnel study meant to looking at how a North Shore line might join in? I hope they do this work so they can at least built the extra foundations or junctions that are needed to minimise disruption in the future when it is built.
I imagine a good alignment would be down Daldy or Beaumont Street, perform a turn under Victoria Park and then head down Victoria Street, under Albert Park and then down Parliament Street and to the old/new station. This would keep it under public land as much as possible and avoid any tall buildings except possibly at the Waterloo Quadrant side.
Going under Victoria Street would make good sense. There are supposedly old tunnels under Albert Park – I wonder if they could be useful.
The tunnels are mostly caved in now, there was a report about opening them up as a tourist destination but it concluded that they are in such a bad state that they would pretty much have to be drilled again. Besides I think they would be too high up to be useful, the entrances are along the the really steep almost cliff like slope and I don’t think they go down at any point, one of the advantages with this tunnel would be that the start and finish of it is more or less the same altitude.
What are the pros and cons of this alignment vs a similar connection to The Strand via new platforms at Britomart instead of midtown?
Going via Britomart would allow the route to run almost entirely under customs or quay st -possibly via cheap cut and cover-, plus it would maintain one central interchange between all bus and rail lines in the city. Going via midtown however would bring shore commuters right into the central cbd wich might be more desirable than prioritizing bus connections. My main concern is the red line above does not connect with the central connector at any point.
I defnitely think auckland needs to plan for a proper rail terminal somewhere. My preference is to use britomart for this role while building new ‘metro’ platforms alongside, but The Strand definitely has merit. There appears to be plenty of room to rebuild terminal platforms there, which could be accessed from both the east and the Parnell branch. I think the main issue would be getting local platforms at the site, particularly on the Parnell side. No good having a terminal station if you can’t get to it on a suburban train.
Nick if you go along Customs St via cut and cover, how would this second tunnel get under the initial CBD tunnel..?
Well unlike the CBD tunnel the Shore tunnel would have basically no height/grade restrictions, as it neither needs to connect to the existing Britomart platforms nor would it need to make that steep climb up to the western line.
So it could cross under or over the CBD tunnel in the vicinity of the Albert/Customs intersection depending on what is easiest. That would probably mean the new platforms along Britomart would be either a bit shallower or a bit deeper than the existing ones. I guess going over the existing tunnel and having shallower platforms would be preferable.
In regard to the specific construction of it, it would be a case of carfully digging around the existing tunnel and constructing a reinforced bridge section above or below it, no major issue there. If they had such a plan on the cards before the CBD tunnel was built they would simply construct it with an underground bridge in the appropriate place.
My red line could go across town anywhere really. It could go under Victoria Street, Quay Street or Customs Street, or even under Wellesley Street I suppose.
To compare this option with Nick’s previous plans I guess you have the following differences:
1) Under my plan the two-track CBD tunnel only serves the blue line and the green line. This means that you can run each line at 5 minute frequencies in both directions. Under Nick’s plan the two-track CBD tunnel may end up having to be used for those lines as well as Howick/Botany Lines or North Shore Lines – all going through one two-track tunnel. So I think my plan has advantages in terms of metro trains running through the CBD.
2) Under Nick’s plan from memory the existing Britomart station remains relatively untouched for use of terminating trains. This means that his option probably works better for inter-city travel than mine does, as I have to send those trains out to the Strand to ensure there’s enough capacity in the Britomart tunnel. Diesel terminating trains from Huapai and Pukekohe are also probably more problematic on my system as you may need to terminate them at Newmarket or the Strand to ensure they don’t conflict with your electrics. Or you give up 2 out of the 12 trains per hour slots on the green line (4 in total, two from the south and two from the west) for terminating trains.
Probably the biggest advantage I see of my plan is that it means you can continue building the CBD tunnel as is currently proposed.
I’ll just add here that my plan is a modification of the next stage of rail expansion, the CBD tunnel, not so much a plan for after that. The idea is to maintain a functional terminal station for diesel trains and build the CBD tunnel for fast metro electrics in parallel, rather than forcing the two to share Britomart and the existing throat tunnel.
In this case we can keep building the CBD tunnel more or less as it is currently proposed, however we would need to extend it a little further from where the project currently stops. All of the work done so far is still valid (I assume they have yet to start on the detailed design of the connection to Britomart under the CPO).
So something like your red line above would still be perfectly feasible as the stage after the CBD tunnel, indeed with any extensions to Botany or wherever. My ‘stage 2’ actually involved new tunnel from the Shore to the Parnell branch and/or the Eastern line, pretty much identical to your red line except it it goes past Britomart instead of Midtown on the way.
It’s splitting hairs but you wouldn’t need four tracks on the eastern to run the Eastern Line and the Botany Line (even with five minute headways on both you’d be ok). What you would probably need is a third (and eventually fourth) tracks for freight accessing the port and for regional and intercity trains heading to terminate at the Strand or Britomart.
Yeah good point about the eastern line probably needing 3 tracks. Although I do wonder whether if you’re triplicating why not go a little bit further and quad-track. I’m sure that fourth track would be handy.
What is your “stage 2” Nick? Tunnels under both Customs and Quay Street?
No quad tracking of the Eastern after the Orakei development…
Well that depends on whether the CBT’s submission gets accepted or not.
*As plans currently stand… LOL…
Yeah I agree the fourth track makes sense if you a building a third, but my point was the two suburban lines could quite happily share a two track railway even at very high frequencies (as long as there were no freights in their way).
Yes, my stage one involves the CBD tunnel with new Britomart platforms under Quay St, while stage two would be the Shore line with similar platforms on the other side under customs St (I can’t imagine this would be much more difficult or expensive that current suggestions to run the line into midtown for example). My idea was to continue this one to connect to the Parnell Branch, from where trains could carry on to at least Newmarket, probably further to Manukau. In my scheme the eastern line already carries both the Botany line and the Ithsmus loop line, so it makes sense to send the Shore line along the Parnell Branch which would otherwise be quite underutilised carrying only the western-southern line.
With some separate freight/intercity tracks and a couple of short city tunnels in the right places, there is no need for more than two tracks on any metropolitan line to give a very high capacity network.