Some people have been a bit surprised that our Congestion Free Network does not expand our existing heavy rail network to a greater extent, particularly given the significant investment currently under way in the City Rail Link. I covered off that issue to some extent a few weeks ago by highlighting that CRL does not have unlimited capacity – one of the reasons we propose complementing the heavy rail network with a new, light-rail, network.
But this isn’t to say that we propose ignoring the (heavy) rail network. On the contrary, we think that it will be essential to work the network much harder over time so that it’s able to perform three key tasks:
- Enable much higher passenger train frequencies, eventually getting up to true “metro style” frequencies of a train every 5 minutes.
- Enable much faster travel times through express trains, especially from the south where the network stretches right down to Pukekohe.
- Progressively separating passenger and freight trains so rail can play a greater part in meeting Auckland’s future transport task
To some extent, these tasks are recognised in ATAP, which says the following about future rail network investment:
The CFN includes these investments, and we envisage accelerating a number of them to enable the strong recent growth in rail numbers to continue into the future. The most pressing investment is a third main between Westfield – Wiri which will allow off-peak services to be increased pre-CRL. This $58 million project is a critical piece of infrastructure. Over time this would be extended to Papakura, then Pukekohe, as eventually a fourth main from Westfield – Papakura too. These additional tracks and trains, as well as removal of road/rail level crossings, will help a lot in letting us get much more from the rail network.
However, a network is only as strong as it’s weakest link and some of Aucklands weakest links are it’s many junctions. We currently have five around the network (Quay Park, Newmarket, Penrose, Westfield and Wiri) and delays at one junction can quickly cause ripple effects around the entire network. To really ensure the network is resilient to disruptions and to get the absolute most out of CRL, we think a couple of further projects not identified in ATAP are likely to be required. These are upgrades to the Westfield and Quay Park rail junctions to become what’s known as a “flying junction”. Flying junctions allowing speedier travel times as rail traffic no longer will need to wait for opposing line traffic to cross. Flying junctions will be built at Mt Eden as part of the City Rail Link project, including one that will eventually be completely underground.
If you look closely at our CFN map on the southern line, you’ll see that trains coming up from Papakura and Pukekohe will skip a number of “inner” stations so they can achieve a faster travel time. This is done by expressing past two sets of stations where the lines already double up: Middlemore and Papaptoetoe, then Greenlane and Remuera. In addition Te Mahia is no longer stops at all, while Penrose is only a stop on the Onehunga branch of the Western Line.
Under this pattern, a train from Pukekohe would stop at all stations to Puhinui before only stopping at Otahuhu, Ellerslie, Newmarket and Grafton before entering the CRL tunnel. This means it would only stop at two major interchanges between the outer southern stations and the edge of the City Centre. All together we estimate this will save around ten minutes off the Southern Line. We think a speed improvement is important when the electrification of the Southern Line is extended right through to Pukekohe with extra stations at Paerata and Drury to serve the growth areas down there. With this Papakura will be about 40 minutes from Aotea, while Pukekohe will be just under an hour despite the two new stations in between.
In the west, the rail network faces a different set challenges to the Southern line. The biggest being that rail freight is far less frequent and usually travels at night so rail congestion is less of an issue. However, the line includes a significant number of level crossings, has closely spaced stations, often close to those crossings, and it follows a relatively indirect route along its course from Swanson to the city. As a result it has slower average speeds than other lines. To truly unlock the transformational impact of the City Rail Link on the western line will require investment to remove level crossings. Those crossings influence rail speeds and capacity, as well as creating localised road congestion. This will only get worse as the frequency of trains increases. The rail development programme endorsed by ATAP between KiwiRail and AT has $585m to grade separate or close level crossings; the CFN 2.0 proposes the same. Removing level crossings will increase reliability, speeds, capacity while reducing localised road congestion.
An extra platform at Henderson is being delivered as part of the CRL to turn trains around, although I personally would prefer to see that at Swanson so the entire line can benefit from improved frequency – under ATs plans stations past Henderson will see no further improvement in frequency at peaks above what exists now.
Increased train frequencies post-CRL may also need a third feed for the overhead electric lines, as well as a fourth platform at Henderson. Other more detailed infrastructure upgrades, such as further upgraded signalling will eventually be required to further improve the capacity of the CRL and wider network. Upgraded signalling as well as improved track-work may be needed to keep reliability high and increase average speeds.
Overall, by building on the significant rail upgrade programme that is already within ATAP, with a particular mind to getting more express rail services to the south, the CFN proposes what would be significant, ongoing, improvements to the rail network.