Dhaka, the capital of Bangladesh, is one of the fastest growing mega-cities in Asia, with a population of over 12 million that is increasing at a rate of around 5% percent a year. The main transport systems operating in the city consist of approximately 200,000 human-pedalled tricycles (locally known as rickshaws), 50,000 motorised three-wheeler passenger vehicles (called baby taxis), and 10,000 buses. All these are in addition to around 100,000 private cars, jeeps and regular taxis.
It is worth pointing out that most private cars and jeeps are chauffeur-driven, and are therefore continuously on the road because they provide service for several people at once. This implies that the actual pollution levels are far greater than the 100,000 figure would suggest.
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The number of motorised vehicles has greatly grown since the mid-1990s and air pollution in Dhaka city has also grown considerably, especially during the dry winter months. Air pollution, especially from particulates, was mainly (over 80%) due to the 50,000 or so baby taxis because they used highly polluting two-stroke engines, which mixed their lubrication oil, usually bought loose and adulterated, along with the gasoline fuel creating lots of smoke.
The pollution load had become so great that Dhaka was being widely touted as one of the top four or five most polluted cities in the world. During the 1990s various citizen groups protested about the high levels of air pollution. The widespread concern and protest about the pollution level in the city provided the Bangladeshi government with a valuable weapon to tackle the vested interest groups that were benefiting from the operations of polluting vehicles. This led to the government, with assistance from the World Bank - under its Dhaka Urban Transport Project - to start a phase-out plan for the two-stroke baby taxis, which were all imported from India. The plan involved an initial ban on further imports of the two-stroke engines (but allowed the cleaner four-stroke alternative) along with the importation of new three-wheelers that ran on compressed natural gas ( CNG ) instead of gasoline.
The process involved stakeholder consultations, mainly with the drivers and owners of the two-stroke baby taxis, including some organised workshops. Key individuals were also invited to visit India to see the system operating in Delhi and other cities - as well as to see the better four-stroke engines available in India.
The phase-out took effect from January 2003 and was immediately followed by some problems as there were not enough replacement engines available. However, with the rapid import of better engines, especially the CNG-powered ones, the situation improved. Since late 2003 almost all the polluting two-stroke engines had been replaced by less polluting ones, and measurements of air pollution have shown considerable improvement over this period. According to World Bank estimates, about 900 premature deaths have been avoided and about $25 million worth of public health costs have been saved.
By making the switch away from the polluting two-wheeler engines within less than a year, the livelihoods of about 86,000 drivers, 600 workshops and 2,600 helpers who collectively support 500,000 dependents have been saved.
Those owners of baby taxis who embraced the changeover benefited by receiving licenses to operate four-stroke (later converted to CNG) vehicles, but those who resisted the change and agitated against the government decision to ban two-stroke found themselves isolated. However, they did manage to recover most of their investment because the baby taxis simply moved to other cities and to the outskirts of Dhaka.
The citizens of Dhaka have strongly supported the efforts to clean the air in the city despite the great hardship endured by most as a result of the sudden transition, and there are now plans to extend it to other Bangladeshi cities. The main lesson learned is that change from polluting to less polluting technologies is possible when the environmental as well as the social factors are taken into account, and when the process is conducted in a way that not only relies on legal and policy instruments but also responds to any perceived losses to a particular section of the community (in this case the baby taxi drivers). Although the transition was not without its problems it was deemed by most people to have been a success.
This article appears as part of openDemocracys online debate on the politics of climate change. The debate was developed in partnership with the British Council as part of their ZeroCarbonCity initiative a two-year global campaign to raise awareness and stimulate debate around the challenges of climate change.
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