Making use of Christchurch’s rail lines – the ‘tram-train’ concept

Posted on September 5, 2011 by


Many people believe that a rail revival must play a role in the future direction of transport policy in Christchurch and as a part of the rebuild and overall new direction for the city following the earthquakes. We have already seen the vision of a light-rail network produced by the City Council as part of its draft Central City Plan, but what of the existing rail infrastructure? It is clear from the plan and various talks from the Mayor that utilising existing rail corridors will form a part of the overall ‘rail vision’, but exactly how we make use of them seems to be an area of some discussion and contention. Therefore, I thought it worth exploring this issue further in a two-part series which focuses on each of two leading options; the tram-train concept and the more traditional heavy commuter rail concept, respectively.

The situation:

Christchurch has a number of railway lines running along key corridors. Essentially, they are:

  • the Main North Line to Rangiora, via (lower) Riccarton, Papanui, Casebrook, Belfast and Kaiapoi
  • the Main South Line to Rolleston, via Addington, Wigram, Hornby and Templeton
  • the Lyttelton Line, through Opawa, Ferrymead and Heathcote
  • the Prebbleton Line (officially the Hornby Industrial Line) via Hornby

In the past, Christchurch had a number of passenger rail services along these lines as well as to country towns further afield. Competition from the growth of car ownership coupled with pro-automobile policies and lack of central and local government enthusiasm meant these services were whittled down to just a few by the end of the 1960’s and disappeared altogether well before the next decade was over. The last suburban service was a single daily service to Rangiora which was discontinued in April 1976 while the last local passenger services of any kind were the boat trains connecting with the inter-island ferry in September 1976 (the once intensive Lyttelton suburban services were discontinued in February 1972).

Since that time Christchurch’s large brick station stood with its platforms empty, serving just a handful of long-distance passenger trains a day. In 1993, passenger rail operations were moved to a new site in Addington, some distance from the CBD. The link between the Main North Line (MNL) toward the city was reversed so it faced Lyttelton, and a few years ago most of that land was developed and had a new road built over it, making any future re-connection pricey and tight. Most of the suburban stations have been demolished with only a handful still existing in some form or another.

This situation obviously presents a number of challenges to the revival of rail services on existing corridors. Perhaps the biggest problem is getting rail services close to the CBD. The previous station on Moorhouse Ave is still there, albeit with no track access and many modifications as well as indirect access from the MNL. It was also never in the best location anyway and, much like the location of Auckland’s old main station prior to 2003, this fact was much lamented. This fact almost certainly played a role in the hurried abandonment of rail services from the 1950’s-70’s.

This means that any revived rail services might have to terminate at both Addington (MNL) and Moorhouse Ave (others), unless Addington junction is fixed (possibly expensive and difficult). In either case, rail services will still terminate at the edge of the CBD, not the most ideal situation. To get rail services into the CBD would therefore require either a tunnel or some other access way, and that would be an incredibly expensive and difficult undertaking for a city like Christchurch that doesn’t yet have any rail services. Much like Auckland has done, the only hope might be to roll out a rail system incrementally with investment made as it can be justified. Rail access further into the CBD could therefore be decades away. Or could it? A new technology is sweeping the world that would allow rail services comparatively cheaper and easy access into the CBD, and many people are keen on it, including the Mayor and Council. This concept is the tram-train, and in this post I will look at what tram-trains look like, the advantages and disadvantages of introducing the system to Christchurch, and some general background and examples.


Tram-trains are rail vehicles capable of operating on heavy rail lines as well as on street tramways/light rail. They usually have dual equipment that suits the respective needs of both a tram and train, including the ability to be dual voltage and even a diesel/electric hybrid. Essentially, when on a railway line they operate much like a normal train, and can switch to operate like a tram on tram/light rail lines via a connecting track.

A Karlsruhe tram-train street running

A Karlsruhe tram-train running on a railway line

The most famous tram-train system is that in Karlsruhe in Germany, which pioneered the idea when authorities wanted to to find an easy way to gain better access for regional rail into the city, instead of requiring rail users to transfer to the tram system. Tram-train systems now exist in a number of cities in Europe including: Alicante, Spain; Paris and Mulhouse in France; and many, many more. Tram-train systems are also now proposed in a number of cities around the world, including in Adelaide, Australia.

Alicante tram-train

A Seimens S70 "Avanto" tram-train on Paris' T4 tramway

A number of tram-train models are currently in production, and most are capable of being modified to suit the requirements of the system they are to run on (e.g. size, style, gauge, motive power etc). Alternatively, it is also possible to order custom-built models should no existing products be suitable, such as in Alicante. My personal favourite is the Siemens S70, or “Avanto”, model which is used in both North America and Europe. It really looks the business, much more like a railway vehicle than a tram and seems to be quite popular. It is used on the MAX light rail network in Portland, Oregon a system that has inspired the rail revival ideas in Christchurch’s draft Central City Plan. Below are links to a couple of videos I found on the Mulhouse tram-train which uses a similar version of the S70 to the Paris T4 tramway. Mulhouse is also a smaller city than Christchurch, which is interesting. The first video shows the tram-trains running in a light rail corridor and in city streets while the second shows them running on the railway line amongst other passenger rail services.



Christchurch and tram-trains:

In Christchurch, tram-trains would operate on existing rail lines much like any other heavy rail passenger trains would. They would leave the rail line to access tram tracks to gain access to the central city and would operate much along the lines of a light rail vehicle.

The advantages of the tram-train concept being applied to Christchurch include:

  • the ability of trains to run into the heart of the city, reducing the need for transfers
  • comparatively inexpensive option to gain CBD access for rail, as opposed to tunnels or viaducts
  • possibility of future extensions that would otherwise be very expensive, e.g. Prebbleton line to Lincoln
  • possibility of fleet integration with proposed light rail network
  • ability to operate on existing railway lines like any other train

There would be no reason for conflict with other rail operations as the tram-trains would operate as trains themselves when on the railway lines, or at least no more problems than traditional commuter rail would pose, such as in Auckland or Wellington. However, there are some disadvantages with tram-trains. There would certainly be a need to address the railway gauge issue (width between tracks) as tram tracks are usually standard gauge (e.g. the current tram in Christchurch) while New Zealand railway tracks are narrow gauge. This could be solved by making the light rail system narrow gauge or by building the links into the CBD as dual gauge (standard and narrow). There will also be issues around capacity as street running might limit the length of trains (as is the case in Portland, Oregon). Depending on what standard the tram/light rail links are built to there might also be issues relating to a difference in service quality between the railway and tram/light rail sections. The work needed to bring the railways up to tram-train running might also be expensive (especially around signalling and motive power) which might rule out an incremental roll out. However, there are, of course, diesel/electric hybrid tram-trains available which would make it easier and cheaper to introduce the concept in the short-term and the rail corridors would probably need adapting, such as new signalling, whatever approach is taken.

A rather crude diagram showing rail line in blue and possible light rail corridor in red that would allow tram-trains access into the CBD

Effectively, a tram-train concept for Christchurch might involve the procurement of light rail vehicles capable of running off electric overhead as well as having onboard diesel engines. Connections between the current heavy rail lines and new light rail lines that run into the city centre could then be made allowing tram-trains to operate on the light rail/tram section via overhead and utilising the diesel engine to run along the rail corridor to Rangiora, Rolleston and Lyttelton. The system could be upgraded incrementally with improved stations and increased passing loops/double-tracked sections (mainly for the MNL as the other lines are mostly double tracked) and eventually full electrification once the expenditure can be justified. In future, further lines (light rail/tram) could be opened off the rail corridors to areas not currently served by rail, for example to Woodend and Pegasus. The Prebbleton line could be reopened and extended to Lincoln via street running, an advantage as the old route through the back of Prebbleton was recently built over.

That is just an off-the-cuff visualisation, there are many possibilities but I hope it gives an idea of how the concept could be applied in Christchurch. In summary, the tram-train concept would allow passenger rail services easy access into the heart of the Christchurch CBD avoiding the need for passengers to make transfers and aiding in the rebuild and revival of the inner city. It is a proven concept that is being increasingly implemented in cities around the world, and there is no doubt it could be achieved without compromising existing rail operations or in turn having them compromise light rail and tram-train operations. In many ways, it is an idea well suited to Christchurch given that rail access into the CBD is poor, we are starting from scratch, and we need to utilise existing infrastructure as best we can. However, it is just one possibility and there are other ways to use the railway lines. I intend to discuss that further in the next post.