I recently read through the Jacobs prepared alignments for AT for the SMART (South-western Multi-modal Airport Rapid Transit) project. In it contains the proposed alignments for HR (Heavy Rail), BRT (Bus Rapid Transit), LRT (Light Rail Transit), as well as a Hybrid option. I would recommend giving them a look but they’re big files so perhaps not on your phone.
The first thing I noticed was for some reason the line names are wrong, I assume this was a mistake. The other and far more serious observation is the lack of a flying junction at Penrose, anybody who passed through here knows that trains can sometimes be sitting for minutes waiting for a free path. And this is with just 8 trains per hour (TPH) each way. I wouldn’t want to imagine the issues at the Penrose junction if trains are running 12-18tph each way. I assume a flying junction would theoretically be possible, though the Great South Road flyover would mean some serious thought would have to go into it, as well as money.
The route from there is basically what you expect, some level crossings are trenched, while others just closed. In a separate, low cost option some level crossings are simply upgraded to be safer rather than removed.
One important change is the Onehunga Station would be moved between Galway St and Victoria St. After passing through the current station site, the line continues over the overbridge currently being removed, and then under the SH20 Bridge to the western side of SH20.
As we’ve discussed in other posts, the trench at Kirkbride is not designed to allow HR at road level due to the grades involved, therefore it must go over the top.
Towards the end is where the real issue arises however, it requires a long tunnel, under the new proposed runway all the way to an underground station by the terminal. The Airport want to lock their plans in now and would be unlikely to allow the line’s construction after the new runway is built. As such this section would likely need to be built before the actual line was funded, this would create a need to accelerate funding either in part or full, not that building it sooner would be a bad thing.
Compare this to the length of Light Rail tunnel needed
Light Rail (LRT) is now AT’s preferred mode, so what does the alignment look like. The first worrying thing about the route is the large park & rides, right next to a rapid transit route on land that could easily handle transit orientated development. The very concerning part is at Denbigh where houses would need to be demolished to build the Park & Ride. Surely stations in areas such as this should be more focused on bus feeder services & active mode improvements to improve catchment rather than Park & Rides. At Mangere surely a more mixed use development could occur by the station.
The second worrying part is getting onto SH20, where additional homes would need to be purchased & demolished. There are surely many other ways that we could achieve access to SH20 without requiring the demolishing homes, I am sure a transit engineer among us would be able to draw them.
Looking at the alignment down SH20, it looks unlikely that both LRT and the proposed Avondale-Southdown line – which the designation is for – could both fit in. Kiwirail allowing AT to use the designation could be a big sticking point for LRT line. However, this route would not preclude an Mt Roskill spur from being built as LRT is only east of the Dominion Rd flyover.
The LRT route continues down SH20 onto Princes Street with two potential alignments around the Lagoon.
From there it elevates over the top of the existing station at Onehunga, possibly joining with a future line from Manukau Rd.
The LRT route then travels down the old rail corridor towards the port and above the NZTA’s planned roadsfest. Like at Onehunga Lagoon there are two options, one is next to the motorway bridge and it crosses onto the western Side of the Motorway south of the harbour. The second option swoops under the bridge like the Heavy Rail option.
Apart from that the route is similar to the video posted by Auckland Transport recently on LRT for SMART.
Now I give fair warning, the following images may cause distress, face palming & nightmares. The route starts with an underground bus station at Wellesley Street, it then continues to an at grade Symonds Street station. It’s not clear where the portal is but it’s unlikely to be pretty.
From Symonds Street it continues to an at grade Khyber Pass station before an underground bus station on Broadway. Not sure how I feel about an underground bus station at Wellesley & Newmarket to be honest :/ maybe we can rename it from Broadway to Busway 😀
Next down Manukau Rd, Pah Rd, and Queenstown Rd with well-spaced stations at Clovernook, Bracken Rd, Inverary Ave, Greenlane West, Pah Rd & Mt A Rd where it joins parallel SH20 Southbound in a new Busway where in parts it becomes a literal Sky Bus.
Similar to the LRT route, it continues down Princes Street into an Elevated Bus Station above Onehunga Station. Then onto SH20 where it has shoulder bus lanes over the bridge and connects to an elevated Mangere Bridge Bus Station, which if you can look closely doesn’t have any Park & Rides which the LRT had?
Lastly it follows the LRT route until Kirkbride where it transitions a BRT median down SH20A, which is rerouted around the end of the runway, until it gets to Tom Pearce Drive
The last option which is the Hybrid option, it simply combines the BRT from Onehunga, to an upgraded Onehunga Line, this would thus require transferring to/from HR.
And finally, here are finally “controversial” benefit cost ratio tables from the report, first the main one with Costs & Benefits assuming a 6% discount rate, and the second testing against 4% & 8%