Imagine you’re the mayor of a fair sized city. You want to improve your public transport network: to improve the local economy, to get traffic off the roads and, if you’re honest with yourself, because you’ve always loved London’s Tube map and you’ve been whiling away idle hours drawing versions for your own city since you were six years old.
There’s a problem, though. You can’t afford to build an underground metro. A light-rail network would cost a fraction of the cost of a subway – possibly as little as 10 per cent. But, when you check the budget, you realise you can’t afford to build one of those either.
So, you’re stuck. Traffic will get worse, employers won’t be able to recruit staff, your tax base will fall, and then one day you’ll find yourself hounded out of office and possibly tarred and feathered in the central business district.
What you really need is a way of building a metro system, with all the reliability and speed that implies, without having to spend all that money digging tunnels and laying down rails. If only. If only...
This was roughly the dilemma that faced Jaime Lerner, the mayor of the southern Brazilian city of Curitiba in the early 70s. (I say “roughly” because I’ve never actually spoken to him. For all I know he hates the tube map.)
And Lerner found a way of getting a metro system on the cheap: much cheaper than a tram; much, much cheaper than a subway. It revels in the distinctly unsexy name of “bus rapid transit” (BRT).
Curitiba’s Rede Integrada de Transporte consists of five express bus routes, that operate much more like a subway (left), as well as wider bus network (right).
Buses provide essential transport links in many cities, but are generally seen as the poor cousin of subways and trams. It’s for good reasons, too. They’re unreliable, suffering from traffic jams just as much as private cars without any of the sense of control. They also stop frequently, making progress slow, even if the road is clear.
They’re also impermanent: you can settle in an area, confident that nobody is going to rip your tube line out of the ground and thus wreck your commute. Rely on a bus route, though, and you may wake up one morning to find it doesn’t exist any more.
BRT systems do away with these problems. They use segregated lanes, inaccessible to other vehicles, to improve reliability (no more getting stuck in traffic jams). They’re often hooked up to the local traffic lights grid, to give them priority at junctions (no more waiting for the lights to change).
They also stop less frequently, and tend to characterise their stopping points as stations (buildings with names, facilities and so forth) rather than stops (bus shelters without them). Throw in floors level with the station platforms and ticketing systems in which you pay your fare before boarding, and you’ve got something that looks a lot like a proper metro network, without any of the expense of putting down rails.
A bus “station” in Curitiba. You need a ticket to get into the station, allowing faster boarding. Image: Morio/Wikimedia Commons.
Oh, and you get a map, too.
A number of cities have included BRT routes in their transport planning. Bogotá’s TransMilenio system includes 144 stops on 12 lines and carries 2.2m passengers a day:
Image: Maximilian Dörrbecker /Wikimedia Commons.
The Los Angeles Metro system includes two MetroBus BRT routes, the Orange and Silver lines, which are treated as part of the MetroRail network.
Even Birmingham is getting in on the act, planning to create Sprint, “the bus that thinks it’s a tram”:
So if BRT is so great – if you can get all the benefits of a metro system at a fraction of the price – then why hadn’t every city built one?
Well, they’re still low capacity compared to a proper subway system. Each train on London’s tube can carry 700-800 people. The articulated buses used on Bogotá’s TransMilenio carry around 150.
What’s more, while they’re cheaper than a full blown metro, they still require spending on infrastructure: segregated lanes, redesigning junctions and so forth. In cities where space is at a premium, it can be difficult to make a case for giving over entire chunks of road to one category of bus.
Some cities are getting around that by putting chunks of their BRT routes in tunnel. But at the point you’re going to the effort of digging a tunnel, you start to wonder whether those cost savings are still stacking up.
This points towards another more political problem with BRT: it’s prone to cost cutting in a way that can render the whole exercise pointless.
When you’ve decided to build a new subway, you’re locked in. You have to dig the tunnels and put in rails and buy rolling-stock and so on.
With BRT, though, it’s possible to nibble away at it. Does it need to be segregated for its whole route? Wouldn’t part be enough? Perhaps to save space, it can share some of its lane with private traffic. Does it really need new stations? Wouldn’t the existing bus shelters do?
And then, before you know it, what you’ve got is basically a bus. Which you just spent quite a lot of money on for no very good reason.
This phenomenon of gradual cost cutting which can render a BRT line pointless has a name: bus rapid transit creep. It’s not a theoretical problem, either. The East London Transit (ELT) was originally meant to be a fully segregated network linking the Barking Riverside development zone to civilisation. In the event, though, the bits of the network that are segregated are mostly those in the development zone, where traffic is low anyway. On the busy main road betwen Barking and Ilford, the ELT shares space with every other vehicle. The stops are the same as any other bus stop, too.
An East London Transit vehicle. If it looks like a bus, and quacks like a bus... Image: Spsmiler/Wikimedia Commons.
And there remains that old problem: buses aren’t sexy, even in their more evolved BRT form. There’s simply more prestige in a subway, or even a light rail network, than in something based on buses.
Perhaps, if Curitiba’s map were to become as great a design icon as the tube map, then that will change. Then again, perhaps not.
Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.