There’s a fantastically interesting post over at Human Transit on comparing the benefits of buses and streetcars (trams), and how it is easy to get blinded by the romance of streetcars rather than looking at the transit problem we are trying to solve and then going about the best way to fix it. Jarrett Walker, a well respected transport consultant who writes this excellent blog, outlines his observation (after making a seriously large number of disclaimers):

Streetcars that replace bus lines are not a mobility improvement. If you replace a bus with a streetcar on the same route, nobody will be able to get anywhere any faster than they could before. This makes streetcars quite different from most of the other transit investments being discussed today.

Where a streetcar is faster or more reliable than the bus route it replaced, this is because other improvements were made at the same time — improvements that could just as well have been made for the bus route. These improvements may have been politically packaged as part of the streetcar project, but they were logically independent, so their benefits are not really benefits of the streetcar as compared to the bus.

While we tend not to have this discussion particularly often in New Zealand, because there aren’t any tram systems left (apart from a tourist circuit in Christchurch), trams may well form an important part of  future public transport investment, so it’s crucial to have a decent look at whether or not they’re worth the (significant) investment.

What is crucial to remember here is that the blog post is only talking about “mobility improvements” and not the potential wider benefits of tram systems. Unlike trains that run in their own exclusive corridors, trams tend not to be able to travel faster than buses, and are not necessarily more reliable. Clearly, if a tram is able to travel within its own right-of-way then it will be faster than a bus that gets stuck in general traffic – however the speed differential is due to the right-of-way issue and not the fact that it’s a tram. Comparing speeds of a tram with those of a bus lane would give a more realistic outcome, and probably tell us that the bus was quite likely faster.

Gosh, this is all sounding quite heretic at the moment coming from someone like me. Like most public transport advocates I do consider trams or streetcars to be superior to buses, but it is certainly necessary for me to ask the question “why”? Is it just because trams are cooler? Is it just because buses are all a bit boring, smelly and noisy? Is it some hazy nostalgia that wants to recreate how cities were in the early 20th century?

The telling thing is that the answer to all the above questions is “no”. While trams are cooler and there may be some nostalgia attached to my desire to see them reintroduced to Auckland, there are some very compelling reasons to invest in trams rather than the cheaper and easier option of only buses. Human Transit outlines those reasons quite clearly, by saying what the paragraph quoted above it clearly NOT stating:

I’m not disputing the ridership benefits of streetcars. Streetcars do attract more ridership than the buses they replace, though it’s not always clear why. There’s an urgent need for more research on how much of the ridership benefits of a streetcar are truly results of intrinsic benefits of the streetcar (such as the ride quality, the legibility provided by tracks in the street, etc) as opposed to results of other improvements introduced at the same time (including speed and reliability improvements, better public information, off-board fare collection, and possible differences in operations culture).

I’m not saying that streetcars don’t promote urban development; clearly they seem to be doing that, though there’s room for disagreement about how much the development really requires the streetcar.

I’m not saying that electric streetcars aren’t quieter and more environmentally friendly than diesel buses; clearly they are, but if this is your only reason for wanting streetcars, electric trolleybuses may meet your need less expensively.

I’m not saying that streetcars aren’t fun to ride. They are.

While the “fun to ride” aspect might be a little trivial, the other three are critically important reasons why trams may be the best transit option even though they don’t necessarily provide a faster journey than a bus. Attracting more ridership than the buses they replace is a crucial sign that investment in trams can very much be worthwhile. A key aspect of this is that developing a tram-line forces an upgrade of the corridor that it runs along – you simply can’t use the current bus stops and you simply can’t get away with not upgrading the road while you put the tram line in.  The second issue, promoting urban development, is perhaps the most significant benefit of investing in trams rather than buses. A tramline provides certainty that services will continue to be run along that route, that they will be provided at a decent frequency (due to the significant capital investment in constructing the tracks) and also provides a “legibility” to the route – that is the route is easy to understand. You know where it will go without having to acquire complex route maps. Finally, the quietness and environmental friendliness of trams cannot be under-estimated. If oil prices do skyrocket in the future then the price of fuelling all our diesel buses will also go up, therefore driving fares up to compensate for the higher cost. If we have an electric streetcar network then we can escape the effects of the oil spike, and public transport can have a cost-advantage over private vehicles. Trolleybuses may be cheaper, but they don’t provide as many benefits.

This is not to say that I don’t agree with what Jarrett is saying in his post – in fact I most certainly agree with pretty much everything he says.  Furthermore, I actually think that his argument is – in a slightly strangely ironic way – very supportive of investment in tram networks. This is because what the post effectively says is “don’t base your arguments for a streetcar network on mobility benefits, because it’s unlikely you’ll find any compared to buses – instead focus on the wider benefits of streetcars and you will have much more luck in finding some real benefits”.

Finally, I also very strongly agree with what he says later in his post about ensuring that you don’t go into a transit project with a set prefered outcome already in mind:

But when the thinking starts with the love of one technology, you’re in danger of producing an inferior transit service, because when compromise needs to be made, technology-first thinking will tend to sacrifice the goals to save the technology. To use my previous analogy, you’ll build an inferior house because you weren’t really focused on building the house, you were focused on how much you like your hammer.

Another way of describing technology-first thinking is that it tends to select and emphasise goals that the favored technology is good at meeting. In our house analogy, it’s as if we told our architect: “design me a house that will require hammering lots of nails!” If a community really does rise up as one and say “the goals served by the streetcar happen to be exactly our goals!” then they should have a streetcar. But too often, the technology advocate ends up sifting the goals based on whether they fit his technology, rather than whether they’re the community’s real goals.

On some corridors in Auckland I do believe a tram line would work very well – along Tamaki Drive and Dominion Road, for example. In the case of Tamaki Drive the legibility and quality of ride would encourage many tourists and recreational travellers to use the tramline who would have otherwise driven, while in the case of Dominion Road I think that a tram-line could encourage significant intensification and redevelopment along this corridor. In neither case is “enhancing mobility” the key argument for conversion to a tram, but in my opinion both cases have a strong justification for a tram line. In other corridors, say Onewa Road for example, I don’t think a tram-line would work as well (even though a large number of buses travel along it each day). This is because once you get to the top of Onewa Road the bus routes branch everywhere – meaning that you would either need to run tram lines all the way to Beach Haven and Glenfield (an enormous cost) or you’d force people into transfering from their bus onto a tram at Highbury shops constantly.

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14 comments

  1. The real benefit of trams is when they are used as part of the Karlsruhe model, and can thus be used on train tracks as well.

    It is also much cheaper to build new rail this way, instead of underground tunnels, and could provide a short term fix for the Britomart access problem. Imagine your proposed tram line, except imagine that in Quay street it joins the Eastern railway line, and uses it to St Johns, and from there uses St Heliers Bay road down to St Heliers. If it uses dedicated lanes, 70kph speed limit (with fences to ensure no kid runs out in front of the tram, short hedges could be more aesthetically apealing) it could be quite popular.Now imgaine a citywide network of these lines.

    You can easily imagine the possibilities.

  2. I’m not so sure I would want the Eastern Line being shared by tram-trains and full heavy rail trains. In a few years time we may well have a train hurtling along the Eastern Line at up to 110 kph every 10 minutes. Slotting in a tram-train that can only go 70 kph between the normal trains might be challenging and operationally disadvantageous.

    But yes, in some cases I can see the advantage – perhaps for a future North Shore Line if the gradients are too steep to easily build heavy rail?

  3. Hi Nicholas,
    I’m not too convinced on the Karlsruhe model myself, except perhaps in niche circumstances. Personally I see the role of trams as being street level ‘metro’ transit for moderately dense urban areas: easily accessible, frequent and suited to routes up to about 10km/30mins in length. Like buses, but higher capacity, faster through more widely spaced stops and dedicated road space, and better ride with a permanent and ‘legible’ route.

    For longer distances or core routes, proper EMU heavy rail with bus feeders and park-and-ride is the way to go.

    In your example, why would you want to run the tram along the eastern rail line? Wouldn’t that skip out the waterfront, Mission Bay, Kelly Tarltons etc, all the things that would make a tram line in the area work?

    Personally I would have a waterfront tram to St Helliers village, keep the eastern rail line running as is and have a high frequency connector bus running between the two.

  4. “I’m not so sure I would want the Eastern Line being shared by tram-trains and full heavy rail trains. In a few years time we may well have a train hurtling along the Eastern Line at up to 110 kph every 10 minutes. Slotting in a tram-train that can only go 70 kph between the normal trains might be challenging and operationally disadvantageous.”

    I’m talking about the tram-trains going at 70kph on normal suburban streets, not on these rail lines. I don’t know too much about the technology, but I’m hoping for at least 90kph on normal train tracks.

    As for the idea of trains being slowed by having to wait for these tram-trains, yes that is a problem. It can be solved by tripple tracking (or quadruple tracking) parts of the network. The other big benefit is it allows more express services, so the normal heavy rail trains won’t have to stop at every suburban service.

    I see your point Nick R. I agree that there may be significent advantages to the waterfront route. Perhaps a better case for the karlsruhe model would be the Onehunga line. At the moment, trains have to terminate at Newmarket, due to limits on the number of trains that can enter Britomart. This seriously reduces the use of the new Onehunga line. Now imagine if the Central Connector could take light rail as well as buses, with 4-5 stops (namely Khyber Pass, Hospital, Karangahape Rd and the Univeristy, so the Onehunga trains could continue all the way to Britomart. This would be far better than forcing people to switch trains at Newmarket.

  5. There is another advantage that tram-trains have over buses. In order to create bus lanes, namely that in order for bus lanes to be effective both directions you need them both sides of the streets, thus taking up a lot of space, and might not be possible on some streets. With the tram trains, they can have single track railways (with a few passing loops included) and thus be used where two way bus lanes might not be possible, or when possible take up less space (and residents can just park cars on the other side of the street, instead of on their property.

  6. I’m kind of in two minds about bring back trams at the moment i don’t see any real to do so. But if the old system never got rip up in the first place i would support improvements to that system but maybe i just want keep the bus funbois happy i have a friend who’s one.

  7. I think that using tram-trains for the sole purpose of overcoming the bottleneck on the rail system would be inferior to simply addressing the bottleneck and building trams where they would be well used!

    Better yet for Onehunga would be a line from Britomart up the Central Connector route to Newmaket and then down Manukau/Pah Rd to Onehunga Mall and the rail station. This gives you two routes from Onehunga to the city, one high speed to the key destinations, the other slower by with greater connectivity. With plenty of opportunity to connect between the two (Onehunga Station, Newmarket Station, Britomart).

    (the central connector is apparently designed to allow ugrading to trams, but we do hear that a lot in Auckland!)

    I must say I think the hammer analogy in the article for ‘technology first thinking’ is a very poor analogy. A tram, bus or whatever is the outcome that will define the form and function of the transit system and be in use every day. A hammer is a tool that could be used to build the house, but would have little to do with the form or function of the house when it was used.

    A better one would be say starting off thinking that modular pre-cast concrete panels are a fantastic technology, and then going to your architect to design a house that uses as many pre-cast concrete panels as possible.

  8. I don’t know much about tram-trains, but they certainly do sound pretty cool. Not sure if we really want to go down the “single-track” path again though. My experience of the Western Line in Auckland has a significant effect on my dislike for single-track railway lines though.

  9. You know what the top 10 (or top few) bus routes in Auckland are by patronage?

    Those routes would probably be the best places to start looking at.

  10. Not sure about the exact routes, but in terms of corridors there are Great North Road, Great South Road, Dominion Road, Onewa Road, Pakuranga Road, New North Road, Manukau Road, Remuera Road and perhaps a few others.

    For some of these corridors they are high patronage/frequency because they are the combination of many many routes from the outer suburbs lumped together (Great North Road & Great South Road being the obvious ones) while in other places the high frequency is because of development patterns (Dominion Road being the classic example).

    I suggest the latter type would be more conducive to being turned into a tram route.

  11. I suggest that perhaps the best place a trial tram-train line would be your Howick-Botany line, as it will be far cheaper as a train-tram than an entirely new rail line (as no riping down houses, since it can use existing roads).

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