I’ve lived in cities famed for their gridlock: 1990s Bangkok (gridlock was as bad as it could be); Los Angeles (gridlock + pollution); New Delhi (gridlock + pollution + honking galore); Nairobi’s gridlock is surely up there.

But is traffic “bad”? What sort of question is that you ask? Surely, the answer is ‘yes’, you say: time wasted stuck in traffic, the frustration, the needless idling of vehicles which creates both local (and global) pollution and so on. But let me suggest this: traffic congestion is also a sign of development. In fact, the more vibrant and dynamic the city as Nairobi surely is, the more traffic congestion you might expect…to paraphrase Gordon Gekko from the movie Wall Street, “Traffic is…good”!

Let’s face it though – you and I don’t like to be stuck in traffic – indeed, who does? So how can one crack the traffic congestion problem in a city such as in Nairobi? Let me touch upon three common — and one uncommon — solutions:

First, the infrastructure solution: Why not build more roads, highways, bridges etc.? Isn’t that an obvious one? Perhaps, but the problem with this approach is the “more you build, the more they’ll come”.  Traffic congestion eases temporarily and it is only a matter of time before more vehicles are added to the road to offset this initial easing (over 10,000 new cars are apparently added to Nairobi roads each month)! Now this is not to diminish the importance of adding new infrastructure when needed: for example, if somebody from the north of Nairobi wants to travel to the south, building bypasses that do not require commuting through the central business district makes complete sense. Indeed, Nairobi has just built about 100kms of new highway (some with bicycle lanes). But as mentioned above, such solutions tend to be “bandaid” ones (i.e. temporary). And the more economically vibrant a city like Nairobi, the less effective this solution.

Second, the public transport solution: Why not put more public buses (or allow private ones) on the road? Why not build a metro rail transit system? While this seems commonsensical, my original home city, Delhi, added a metro system only as recently as a few years back. My last home city, Washington DC, has yet to complete a public metro train line that links the nation’s capital’s international airport to the city! And my current home city, Nairobi, does not have a metro rail system. It does, however, has customized, private mini buses, called “matatus” (which as an aside, are an artistic and cultural phenomenon of their own). But these too are victims — and contributors — to gridlock. There is a growing market for bodas –bodas (inexpensive motorcycle taxis) but they are not yet as reliable as the motorcycle taxies (“motos”) I relied on living in Bangkok: zippy and inexpensive two-wheelers that weave and whiz past stalled luxury BMWs and Lexus-es, guaranteed to get to your destination pretty much on time (just hold on to your knees though)! So why don’t we have more public transport? Metro rails? Motorcycle taxis? I do not know but one typical reason elsewhere is the local political economy — existing vested interests often block the emergence of new, efficient forms of transport. And this is not just a developing country phenomenon – when I moved to Los Angeles in the late 1980s for study, there was no public transport whatsoever (and I had to buy a car out of necessity). You see, historically, the Big 3 American automotive companies systematically blocked the emergence of public transit in California because of their desire to sell more cars!

Third, the information solution: Ever-innovative and enterprising Nairobians have begun marrying traffic and technology, and have even developed an app for it. “Ma3Route” is a mobile phone app that crowdsources traffic information. Linked to twitter, it provides live feeds to its subscribers to help them avoid / bypass local bottlenecks. In addition, an IBM team has put forth a plan of using readily available technologies such as cell phones; CCTV; GPSs in Nairobi etc. to make traffic information more readily available both to drivers and traffic police. That can help pinpoint traffic congestion bottlenecks in real time and better manage congestion, and the Nairobi count government is considering adopting key proposals of this plan. A common feature of this approach is providing live, accurate information to permit real-time trip scheduling / routing. My feeling is that these improvements in information help but mostly on the margin…so the question remains: how to make a big, systematic dent? Read on…

To make a dent, here’s the “uncommon” economists’ solution that some of you might be familiar with. It builds on the economist’s zeal of improving complex social systems / behavior by changing incentives, in this case, through the price mechanism. Why not simply charge people for the costs of congestion they impose on the system? Urban transport experts tell us that traffic congestion is “non-linear”, i.e, once traffic goes beyond a certain threshold even by a small amount, the cost of congestion (say, measured in delays) shoots up exponentially (intuitively, because of driver reaction time delay. For a slightly more technical explanation, click here). This non-linearity then suggests that discouraging even a small number of people to not drive during peak rush hour can lead to big improvements in traffic congestion. How do you do that? Start charging a small fee (called “congestion pricing”) in peak rush hour. Now this was first experimented in one of my adopted home cities, Singapore. In the late 1990s, Singapore introduced the Electronic Road Pricing (“ERP”), which is a usage-based, real time, road pricing system. And it did precisely that – it starting charging drivers a small fee based on the congestion they impose on the system (so higher fee during rush hour and vice-versa), and in conjunction with the three common solutions above (decent infrastructure; reliable public transport; making use of available technologies), pretty much solved its gridlock problem. Having lived in Singapore and experienced it firsthand, it is indeed a real marvel! And this has taken off in other places. Toronto, and more recently, London and Stockholm have been inspired by the Singapore model, and have introduced congestion pricing to much success. Now you might think that people would object strongly to pay for something that used to be free. And you’d be right — when first introduced, Singapore’s ERP was nicknamed “Everyday Rob People”. Not anymore though. Similarly, what happened in Stockholm is illuminating. There was the initial, expected resistance but now a majority of users so strongly support congestion pricing that it being extended to Sweden’s largest city — Gothenburg. Of course, these solutions are not mutually exclusive – you do need to build and maintain roads and you do need decent public transportation alternatives. But good old-fashioned incentives work on us humans and can do magic.

This post first appeared on The World Bank’s Future Development Blog

Author: Apurva is the World Bank’s Lead Economist for Kenya, Rwanda and Eritrea.

Image: Vehicles move along New Delhi’s Connaught Place during evening hours, October 28, 2014. REUTERS/Anindito Mukherjee.