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World Resources 1996-97 (A joint publication by The World Resource Institute, The United Nations Environment Programme, The United Nations Development Programme, and the World Bank) (Data edited by Dr. Róbinson Rojas)
4. Urban Transportation
Improving the Transportation Supply
Even though mechanisms such as road pricing may be able to reduce travel demand, there is still a considerable need to expand the transportation infrastructure in many rapidly growing urban regions, particularly in the developing world. In many urban areas, the transportation infrastructureincluding roads, sidewalks, crosswalks, and railwaysis seriously deficient. Poor road surfaces lead to safety hazards, congestion, and premature vehicle aging, as well as increased fuel consumption, pollution, and maintenance costs.
The challenge, however, is to expand and improve the transportation supply in such a way that the automobile is only one part of the transportation system rather than the focus. Tools for discouraging the overreliance on privately owned cars will not work unless people are given fast and efficient transportation alternativeswhether bus, light rail, subway, walking, or cycling. Indeed, travel patterns in a city mirror that city's commitment to providing roads, parking, and transit service (126).
Public Transit Expansion
For cities in need of expanding their transportation supply, developing a mass transit system, with its effective use of space and lower per-passenger pollution levels, should be a priority option. (See Table 4.3.) From buses that provide flexible and low-cost transportation to subways, cities have a wide array of choices. The options best suited to a particular city depend on a number of factors, including urban form, density, and wealth.
In most cities, efficient bus systems can be both affordable and effective. Buses can carry as many as 80 passengers during the peak period (and trams can carry even more), yet they take up the space of no more than two privately owned cars (127). Indeed, buses are the transportation choice of a majority of city dwellers in developing countries, especially the urban poor. In 1980, an estimated 600 million trips per day were being made in buses in cities in the developing world; that figure will double by the year 2000 (128).
Yet, despite its vital role, bus service in many places falls far short of demand; systems are often severely overstretched, uncomfortable, and unreliable. Potential passengers increasingly turn to other modes of transportation (especially as incomes rise and cars become an option) or are forced to walk long distances. Buses also tend to be noisy and polluting. Regular maintenance can help improve their safety and reduce emissions. In some cities, buses have been retrofitted with engines that run on compressed natural gas (129).
As long as buses run on the same congested streets as other vehicles, they will never be an attractive alternative for those who can afford a car. An effective way to increase bus ridership is to give buses priority in traffic. A dedicated bus lane (assuming high-occupancy rates and efficient operation) can move twice as many people per hour as buses operating in mixed traffic and 40 times as many people per hour as cars (130). By giving buses priority over car traffic, more people will turn to buses as a fast and efficient alternative (131). Many European cities, including Zurich and Helsinki, Finland, have designed systems that give priority to buses and trolleys at intersections (132).
In Abidjan, Cote dIvoire, a system combining exclusive bus lanes with a high-speed bus network has enjoyed considerable success. It not only cut bus trip times in half and relieved congestion, but also enabled the government to postpone planned infrastructure investments of US$120 million between 1981 and 1984 (133). One of the most effective bus systems is in Curitiba, Brazil, where the integration of guided land development and a public transportation network created conditions that naturally promote bus use (134).
In Canada, the city of Ottawa, Ontario, is developing an extensive busway system rather than a subway system because of its comparatively low cost and flexibility in serving low- to medium-density urban areas. In addition to exclusive bus lanes, the city is considering a bus tunnel in part of the city center and will promote the use of alternative fuels, including compressed natural gas and electricity, to help alleviate related emissions problems. The system has been designed so that it could be converted to rail transit if warranted (135).
Well-planned and well-used light rail systems can move more people than can buses. Light rail systems also consume less energy than buses and, depending on the power source, emit fewer pollutants (136). Light rail systems, such as trams and trolleys, although slower than heavy rail systems, can carry 6,000 people per hour in mixed traffic and up to 36,000 people per hour with five- or six-car trains, exclusive rights-of-way, and grade-separated intersections (137). Light rail systems have certain drawbacks, including system inflexibility and expensive track maintenance (138). However, in the dense cities of Asia, light rail is becoming increasingly attractive and viable (139).
Rapid rail transit, such as subways, often appear to be the ideal solution to clogged city streets. These rail systems promise high mobility, can be built under valuable urban land, and, because they emit relatively few pollutants, are an environmentally attractive alternative. Yet, construction and operating costs are huge and often prove to be excessively burdensome on city bud-gets (140). For example, a dedicated underground rail system cost $40 million per kilometer in Santiago, Chile, $64 million in Osaka, Japan, and $117 million in Caracas, Venezuela. In comparison, a surface light rail system in Tunis, Tunisia, cost only $29 million per kilometer (141).
Cities should resist the temptation to pursue flashy advanced technology solutions when lower-cost approaches such as buses might be adequate. A phased approachfirst identifying transport corridors well in advance of city growth and then upgrading services from dedicated busways to light rail and finally, perhaps, to a subway system may be the best way to ensure the development of economically and financially sound transit systems (142).
Improving Existing Public Transit Services
Opportunities also exist to improve and upgrade existing public transit systems. One option is to privatize and deregulate bus services. Competition among private bus companies can improve bus services and reduce costs. In Colombo, Sri Lanka, for example, deregulation allowed small bus owners to compete with the public bus company, substantially improving service coverage and quality (143).
At the same time, a completely deregulated and competitive public transport market can have pitfalls. Private companies may concentrate services in areas with high densities and high-income neighborhoods, leaving the poor on the urban periphery without adequate services (144). In Santiago, Chile, the complete deregulation of the bus system in the 1980s resulted in large numbers of poorly maintained buses clogging the main streets, contributing to pollution and endangering riders. To correct these problems, the city recently adopted a comprehensive scheme of auctioning downtown routes. Companies must be able to comply with emissions, safety, frequency, and cost requirements before they can be granted rights to various routes. By promoting competition in the market in this way, buses are cleaner, fares are lower, and service is more uniform (145).
Informal transit services that cater especially to the needs of the poor, such as the jeepneys in Manila or the kabu- kabus in Lagos, Nigeria, are an important part of transportation systems in developing country cities. In Ankara, Turkey, dolmus minibuses have been operating for 40 years, providing about 29 percent of transport trips. These vehicles, which operate without timetables, provide more frequent services than municipal buses. Their small size allows them to maneuver more easily on narrow, winding streets (146). In Africa, similar informal transit services fill a critical need for the urban poor (147). However, these informal services are often polluting and tend to contribute to congestion. They also reflect the failure of public transportation to meet the needs of city residents. Integrating these services into the formal transportation network and improving the safety and efficiency of the vehicles could improve transportation options for the poor.
Improvements in public transportation services may also attract new users. In many Western European cities, including Paris, Zurich, and Hanover, Germany, integration of fares and services across transit modes (e.g., bus to rail) has made public transportation use easy and competitive with the automobile in terms of travel time and comfort (148). Although improvements to public transportation systems bring in more passengers, they tend to have only a limited effect on the use of privately owned cars, and thus on congestion and emissions, even if transit travel is increased substantially. The majority of new public transportation users tend to be former pedestrians, cyclists, or car passengers (149).
Making Cities Friendly to Pedestrians and Nonmotorized Vehicles
In the automobile age, nonmotorized transportation is often given short shrift. However, if properly promoted and encouraged, bicycles and walking can provide access to shopping, schools, and work. For cities plagued by serious traffic congestion and air pollution, nonmotorized transport can be an important alternative to relying on private vehicles and can serve as a link in an integrated public transportation system. (See Box 4.3.)
Bicycling and walking are often the only means of transportation available to the poor in many urban areas--particularly in Asia. Indeed, more than half of the world's 800 million bicycles are estimated to be in Asia, with more than 300 million in China alone (150). However, many cities have imposed constraints on nonmotorized modes of travel, particularly cycle rickshaws, claiming that they cause congestion or unfairly exploit human labor (151). In other cities, lack of access to credit inhibits the greater use of nonmotorized vehicles. Many people are unable to save enough money to buy a bicycle (152). Yet, if their use is encouraged, nonmotorized vehicles can provide the mobility needed to improve the economic welfare of the poor. In addition, they can boost public transportation services by serving as a link between outlying settlements and public transit routes. It is common to see thousands of bicycles parked outside train stops in cities in India and China (153).
In China, 50 to 80 percent of urban trips are by bicycle. The government has actively promoted bicycle commuting by offering subsidies to those bicycling to work. It has also accelerated bicycle production and has allocated extensive urban street space to bicycle traffic (154). In Havana, Cuba, an ambitious government program to encourage bicycle use prompted by the country's petroleum crisis has helped to reduce car traffic by 35 percent and bus traffic by 50 percent. One of every three trips in the city is made by bicycle. In addition to subsidies and bike lane construction, the city has reduced car speeds on the most heavily traveled roads to improve safety conditions (155). Other important steps in making bicycles an attractive alternative include separated road space so that nonmotorized vehicles do not have to compete with and disrupt traffic and regular maintenance of bike and pedestrian routes.
In developed countries, far fewer people depend on bicycles and walking as their primary mode of transportation. In the United States and Australia, for example, only 5 percent of all trips involve cycling or walking (156). For these modes of transportation to become more widely used, cities will have to promote them by improving safety conditions for bicyclists and pedestrians, providing bicycle parking, and creating links with public transportation. Denmark and the Netherlands have perhaps done the most to promote bicycle use, although local culture and flat landscapes have played important roles in maintaining the popularity of the bicycle in those countries. Despite already high levels of bicycle use, the Dutch national transportation plan aims to increase the amount of cycling by 30 percent by 2010 by providing new bicycle routes, parking at railway stations and bus and tram stops, and additional safety measures (157). Extensive bicycle paths have also been introduced in several cities in Canada and Australia (158). In Seattle, all 1,250 buses in the metropolitan transit system are now equipped with bicycle racks (159).
Reducing Vehicle Pollution
At the same time that cities try to discourage car use and shift the travel load to other alternatives, they can also take a number of steps to improve air quality by reducing vehicle emissions. This can be achieved by cleaning up the fuels that vehicles burn, promoting the design and market penetration of new vehicle technologies, and improving the performance of the existing vehicle fleet.
Alternative fuels, including compressed natural gas, liquid petroleum gas, and ethanol, are receiving increased attention as potential pollution reducers (160). Compressed natural gas, already being used in countries such as Canada, Italy, and New Zealand, is an abundant fuel and can be particularly useful in reducing emissions of particulates (161). In Brazil, an ambitious government initiative in support of ethanol reduced the share of gasoline used for transportation from 56 percent in 1971 to 23 percent in 1992 (162). By 1983, 90 percent of all new cars ran on alcohol (163). As a result of this change in the fuel mix, energy efficiency in the transportation sector grew significantly between 1971 and the mid-1980s (164) (165). Recently, alcohol shortages and poor road and car maintenance have begun to threaten the potential benefits of the program (166).
A high priority for developing countries is to reduce the lead content in gasoline. Besides being a direct health threat, lead in gasoline prevents the use of catalytic converters on gas- burning engines; catalytic converters help limit vehicle emissions of hydrocarbons, carbon monoxide, and nitrogen oxides (167).
The costs of eliminating lead from gasoline and of eliminating older vehicles have made it difficult for lower-income countries to switch to unleaded gasoline. In Bangkok, however, the government has supported the introduction of unleaded gasoline through a tax subsidy. By taxing unleaded fuel less than leaded fuel, the government made it cost-effective for local refineries to produce unleaded gasoline. In January 1996, use of unleaded gasoline became mandatory (168).
New Vehicle Technologies
Opportunities also exist to improve the efficiency and cleanliness of motor vehicles. One promising alternative is the adoption of motor vehicles that run on electricity, powered by fuel cells, hydrogen, or some combination thereof. Zero emission vehicles, while having no effect on congestion, could greatly improve air quality, improving health and the quality of urban life (169). Although some cities and countries have begun to replace public buses with electric models, the wide-scale adoption of electric vehicles remains uncertain. In California, an ambitious mandate requiring that 2 percent of all cars sold in the state in 1998 be emission free was recently amended due to political pressure and reservations about the current performance capabilities of electric vehicles (170). (See Chapter 3, "Urban Impacts on Natural Resources." ) In the developing world, the high costs of these technologies make it unlikely that most residents will be able to afford them for many years to come.
Vehicle Inspection and Maintenance
Older vehicles account for a disproportionate share of air pollution. A badly maintained older vehicle can emit 100 times the pollutants of a properly maintained modern vehicle (171). In Los Angeles, one study estimated that pre-1971 cars, which accounted for only 3 percent of the total vehicle miles traveled, were responsible for 50 percent of total hydrocarbon emissions (172). Effective inspection and maintenance programs can reduce emissions from old vehicles and ensure that new vehicles remain in good condition. According to U.S. data, a well-run inspection and maintenance program can reduce the carbon monoxide and hydrocarbon emissions of an individual vehicle by up to 25 percent (173).
Such programs are especially critical in developing countries and countries in transition, because much of the vehicle fleet is composed of older and generally more polluting cars. In Jakarta, Indonesia, for example, two thirds of the privately owned cars are 5 years old or older (174).
However, inspection and maintenance programs face financial, administrative, political, and enforcement barriers. Beyond that, the results of such programs can be mixed. California recently found that only about 50 percent of the repairs arising from inspections were effective in reducing emissions (175).
Singapore, Taiwan, Thailand, India, the Philippines, Chile, and Mexico have all implemented at least rudimentary inspection and maintenance programs (176). Quezon City, Philippines, began an Auto Anti-Smoke-Belching Campaign in 1993. After a 6-month "benign phase" that educated the public about the health hazards of air pollution and the need to reduce auto emissions, the program moved into its "malevolent phase." Two teams randomly tested about 200 vehicles on city streets each day. The owners of vehicles that failed the test (about 65 percent) were fined, had their licenses and registrations taken away, and were given 24 hours to have their vehicles fixed. More than 95 percent of vehicles passed the second test (177).
Another effective mechanism that can be used to reduce vehicle emissions is to accelerate the disposal of old and inefficient vehicles. In Budapest, Hungary, the city government will exchange public transportation passes for Trabants and Wartburgs, two brands of automobiles that are highly polluting but widely used in the city because of their low cost. For each Trabant, the city awards four year-long passes; for each Wartburg, six year-long passes are issued. In addition, the program will buy these cars for a price higher than the going market rate if the money is used as part of a down payment on a new, more efficient vehicle. So far, an estimated 2,000 Trabants and Wartburgs have been taken off the streets of Budapest (178).
Two-wheel vehicles pose an even greater air pollution challenge, especially in Asia. Two wheelers are responsible for a majority of respirable particulates in the air of many Asian cities (179). Given the sheer number of two-wheel vehicles in Asian cities, imposing strict emissions standards is difficult. However, emissions reductions are possible at modest cost by switching from two-stroke to four-stroke engines or by installing catalytic converters. In most cases, the initial increased cost is offset by improvements in fuel economy (180).
Putting It All Together
Each city faces its own mix of transportation problems, and each city will require its own combination of policies to address them. Heavily car-dependent cities, such as those in the United States, face significant challenges. Extensive land use changes, however desirable, are difficult to implement. Given the extent of the existing transportation infrastructure--and the expense implicit in expanding it further--these cities must focus on maximizing the access that their current systems provide and on improving the efficiency and cleanliness of existing vehicle fleets (181). Still, these strategies need not preclude longer- term goals of increasing densities in cities.
Cities in less developed regions of the world, where urban form is not strongly focused on the automobile, have perhaps the greatest opportunity to ensure that future development patterns effectively manage the demand for transportation. For these cities, the key issue is anticipating the growing demand for access and addressing it before an irreversible commitment is made to an unsustainable lifestyle and urban form (182). Yet, they also have the fewest financial, technical, and institutional resources. Historically, measures to address the environmental impacts of the transportation sector are not introduced until well after the impacts have become acute. For example, Bangkok, London, and Tokyo did not begin to address automobile emissions until residents perceived that the air pollution situation was dire (183).
Perhaps the greatest single barrier to effectively solving transportation problems, regardless of city size and location, is the fact that the responsibility for urban transportation systems resides with many different entities. Typically, one institution is responsible for air quality management, another is in charge of traffic management and enforcement, a third manages public transportation, and a fourth manages the infrastructure. This fragmentation can be further complicated by the existence of several municipal and political structures as well as the presence of various politically influential transportation providers (e.g., taxi commissions, public transport associations, automobile clubs, and freight carriers).
The proper institutional structures will depend on the specific political and institutional context of a metropolitan region. However, without clear lines of authority and strong coordination, any attempts to improve urban transportation systems will inevitably fall short.
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