Paris and Mumbai are rarely mentioned in the same breath, yet both cities share uncanny similarities. Both are facing a steady influx of immigrants; both have a population density of 21,000-23,000 people per square kilometre; both are fairly cosmopolitan; and both have arch-like monuments that have become iconic landmarks (the Gateway of India and the Arc de Triomphe).

Both cities also hold valuable lessons for Singapore, from urban planning to population control to environmental management (both cities are litterstrewn). But more pertinently in the context of this article, there are things we can probably learn from the two in the area of traffic management. I say “probably”, made during the time I spent in the two cities in June.

Like the city as a whole, traffic in Mumbai is an assault on the senses. With horns blaring, a kaleidoscope of road users fills the tarmac each and every moment of the day – from tuk-tuks to jaywalking pedestrians, from Porsches to cows, from giant trucks to mini-sized Nanos. The roads are heavily utilised and chaotic, with drivers and riders who pay little or no heed to traffic signals, and with certain junctions (major ones included) that aren’t even signalised.

Yet there is an order to the madness, and no one seems to lose his cool. Horns are used incessantly, but they are to warn rather than rebuke others. Like the seemingly unruly movement of an ant trail on an unmarked forest path, the flow of vehicles on roads evidently too small to hold them is steady and rarely interrupted.

The secret to this unorthodox efficiency lies in how rows of vehicles are almost always more than the number of lanes in a carriageway. For instance, a three-lane carriageway will have five rows of vehicles.

This way, the capacity of any road automatically increases beyond its infrastructural design, and with that, efficiency also increases.

Travelling speeds, of course, are low, but speed isn’t always a good indicator of efficiency. At lower speeds, the gaps between cars can be smaller. Also, at lower speeds, drivers are better able to avoid accidents, which can cause major delays. Assuming the gaps between vehicles aren’t any different from those here, five rows of cars moving at 30km/h along a three-lane carriageway in Mumbai will offer the same efficiency as a three lane carriageway that allows an average speed of 50km/h. Efficiency, after all, is measured by the number of vehicles clearing a particular stretch of road over a particular span of time.

Drivers in Paris face a similar situation. Usable lanes are narrow within the city, as buses and cyclists often have demarcated space reserved for them. And where there aren’t any bus or bicycle lanes, kerbside parking often reduces road space to one lane per direction. Not only that, there are plenty of junctions. Besides the usual cross junctions, there are junctions of various permutations, made more challenging by a confluence of one-, two and sometimes three-lane carriageways.

Driving in Paris requires your full attention if you are to avoid a collision. Even when the lights are in your favour, there are often broken lines to indicate that you have to give way to traffic on a bigger road that you are crossing.

Hence, speeds are low. And because of that, the accident rate is low (France has among the lowest road fatality rates per million vehicles in the European Union). Speeds are low also because there are many signalised pedestrian crossings. And quite often, the “green time” for pedestrians is as long or longer than the green time for vehicles. Even along the 10-lane Avenue des Champs-Elysees, there are a number of such crossings.

Because of these conditions, drivers feel less compunction to make jackrabbit starts, knowing full well that they will have to come to a stop soon afterwards.

And like in Mumbai, there is a strong culture of giving way. Filtering or merging vehicles seldom have difficulty. Drivers wave or activate the hazard lights once to say “thanks” in return.

I thought it would be a nightmare to negotiate the massive circus around the Arc de Triomphe, but to my surprise, drivers already in the circus gave way to merging traffic, and no one had any difficulty exiting either. Even trishaws catering to sightseeing tourists negotiated the epic roundabout without incident.

Even on a highway where traffic has come to a crawl because of roadworks, drivers move slightly aside to make way for ambulances to pass between lanes.

This is unthinkable in Singapore. Drivers here are so inflexible and filled with self righteousness that if they were stuck in a similar jam and a siren is blaring behind, they will shrug and think, “What can I do?”.

And when the traffic lights at a junction here are faulty, there’d be a tailback of vehicles as drivers struggle to cope with a situation where they have to exercise some courtesy and common sense. In Mumbai this would simply be par for the course.

According to the Singapore Traffic Police, inattentiveness is the top cause of accidents here. Methinks it is inconsiderate behaviour. If we all can adopt a “live and let live” attitude, and share road space more willingly, traffic efficiency will improve immensely. We don’t need to resort to forming five rows on a three-lane carriageway, but a bit of tolerance, yielding and graciousness will go a long way.

As for traffic engineers, perhaps the lesson here is that “free-flowing” speed isn’t the ultimate measure of efficiency. For one, if roads are designed for “optimal” speed, drivers will feel entitled to go fast (despite legislated limits). In fact, actual urban speeds in Singapore could well be the highest among developed cities. Ironically, speed tends to breed impatience as well as inculcate a “last-minute” mentality.

As a result, the accident rate here is high, with the average motorist experiencing a collision (minor or major) about once every five years. This compares with one in 10 years in America. And accidents, obviously, lead to a massive drop in efficiency.

This article was written by Christopher Tan, consulting editor for Torque.