Travelling on the streets of Mumbai is no easy task. In a city of 18 million people with a population density of 22,000 people per square kilometer, one can expect to dawdle wearily in traffic, inching forward at no more than about 5 or 10 kilometers per hour. The same road space is shared by buses, cars, motorbikes, three-wheelers, bicycles, wheelbarrows, trucks, throngs of pedestrians, street dwellers, and hawkers that constantly come within inches of
disaster. The train is a dangerous alternative; 4,000 people per year are killed crossing the tracks or falling out of over-crowded compartments.
In Mumbai, Delhi, Karachi, Jakarta, Beijing, Lagos, or any mega-city in the developing world, the problems are the same. Transportation in developing country mega-cities (i.e., cities with a population of 10 million or more) is in a state of crisis. Extreme congestion, long commute times, choking air pollution, deadly traffic accidents, and inadequate public transport are the norm. Billions of dollars in economic productivity are lost due to congestion. Air and noise pollution severely impact health and quality of life. The poor lack affordable or comfortable mobility. Transportation is also one of the most significant contributors to climate change, accounting for 25 percent of global emissions (IEA, 2003).
Continued rapid urbanization, particularly in the mega-cities of Asia and Africa, is magnifying the problem. Already, more than 50 percent of the world’s population lives in cities. By 2030 that figure is projected to jump to 80 percent, with 90 percent of that growth taking place in Asia and Africa. By 2020, Mumbai, Delhi, Mexico City, Sao Paulo, Dhaka, Jakarta, and Lagos will join Tokyo in a new category of meta-cities with populations that cross 20 million people
(UNFPA, 2007). The already overwhelmed transport systems in these crowded centers will have to adapt to massive population influxes, coupled with increased personal vehicle use.