When a horse is crossed with a donkey, you get a mule. What do you get if you crossbreed a subway and a bus? The answer: busway, or BRT ("bus rapid transit").

This transport hybrid could be the answer for many not-so-well-off countries in cutting down carbon dioxide emissions. It is a shining example of ingenuity and sincerity bearing fruit in our fight for global survival.

The idea is a simple one: assign a substantial portion of the arterial roads in the city and make them bus-dedicated corridors. Build modern enclosed above-ground stations along intersecting strategic lines linking densely populated districts. Schedule a stream flow of high-capacity specially designed trolley buses with multiple doors. Off-bus fare collection allows passengers to board through all doors of a stopped bus.

A bird's-eye view of the elevated BRT system in Xiamen, Fujian province. File photo

Just about every metropolis on earth aspires to set up subway networks, so why should we consider a BRT?

It takes 15-50 years to build a metro network. Some poor countries might take forever to acquire one. The BRT is some 30 times cheaper, and it takes a few years or less to realize. Thus, it combines the advantages of a metro system (noticeably, right-of-way, which improves punctuality and frequency) with the advantages of a bus system (low construction and maintenance costs, low vehicle costs, right-of-way not required for its entire length and, if serviced, the capability to join feeder bus services to a trunk busway).

It removes thousands of smaller buses and cars from the road, thereby cutting down fuel use and attendant carbon dioxide emissions, along with toxic chemical cocktails, by some 60 per cent.

This innovative transport scheme was first pioneered by the Brazilians in South America, who set up the first one in 1974 in Curitiba. Another recent success can be found in Columbia, Bogota, where the BRT system now moves more passengers per kilometer every hour than almost any subway anywhere. Mexico City, Cape Town, Jakarta, Ahmedabad and other cities around the world are now copying this idea.

While the Brazilians' imagination and determination are to be admired, it would be naive to think that this could be a panacea for traffic problems in all cities. Experience has shown that at least three conditions must be met to make it work:

1. Flat topography for building wide and straight boulevards.

2. Cooperative road users (New Delhi BRT's failure was partially due to the large number of oxen and camels wandering around town).

3. The absence of a car culture that guarantees formidable resistance to the limitation of their use.

Now you see why no one in Hong Kong has ever heard of the BRT. We have met none of these three preconditions. Indeed, our car owners rule the roads as well as the Legislative Council! Allot one lane on Nathan Road to rapid buses? Not even over their dead bodies.

One color label for each district

Given that Hong Kong has few long, wide roads for such a purpose anyway, and now that the community is waking up to the reality that building more roads, flyovers and tunnels only encourages more car use and therefore more pollution, greenhouse gas emission and traffic nuisance, what else can be done here to save the day?

Years ago, this writer came up with a road-pricing idea that could ease our road problems in no time. Identify a dozen or so districts suffering from traffic congestion and air pollution, and assign a price tag to each. Oblige all private vehicles entering any of these regions to display on the front window valid specifically colored licenses, with a heavy fine for failing to do so.

For example, you must show an orange label to drive into Wan Chai. For private cars, that would cost a thousand dollars to renew every three months. The blue one for Mong Kok costs two thousand, while the brown Lai Chi Kok and the yellow Kennedy Town labels could cost a mere four hundred each. Typically, a city center resident's car would require two or three of those licenses, while a service truck might need quite a few more.

Has no one ever thought of this? Sadly, such a drastic proposal would never pass through our bureaucratic production line and be endorsed by the legislature - not until the day when our culture is convinced that life without a private car is better for everyone.

Having said that, it would be fair to note that our government is, at long last, getting serious about extending pedestrian zones and building more railways and bicycle lane networks. These are small steps in the right direction, but there is a long way to go. The car hegemony will only give way when you and I fully embrace a green commuting philosophy. When are you buying your bike?

(HK Edition 08/08/2009 page7)