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

MOVING FORWARD: KEY STRATEGIES AND TOOLS

Faced with rising transportation demand and growing negative impacts, urban areas require new approaches to addressing their transportation needs. Cities cannot continue to expand their urban transportation systems forever. Although some expansion is necessary, the economic, social, and environmental costs of doing so are prohibitive. Instead, cities need to reexamine urban transportation demand and devise new strategies that provide maximum access at a miminum total cost.

A number of policy tools are available to reduce excessive travel demand and create more sustainable transportation systems, from road pricing to increasing the efficiency of existing systems, to expanding public transit. Most of these tools will have a limited impact if they are used in isolation. Instead, improving urban transportation systems will require a combination of policies that reinforce each other and help to avoid adverse side effects (92).

Managing Travel Demand

Land Use

Perhaps the greatest opportunity to reduce the negative impacts of current transportation systems is to influence land development patterns. An integrated land use and transportation strategy can increase the accessibility of jobs, shops, and other facilities without increasing the need to travel by car.

Many urban planning models have proposed ways to reduce reliance on the automobile. Some point to the compact city as the ideal, where high densities facilitate walking or bicycling and buses or subways are cost-effective alternatives. The mixed land use model, where homes, jobs, and stores are clustered together, can reduce car trips and address the problem of deserted central business districts at night. Other models present the ideal form as many small, self-sufficient urban centers linked by a public transportation system. Greenbelts, greenways, and urban growth boundaries--large tracts of land on which urban development is prohibited--are heralded as effective means of protecting farmland and preventing urban sprawl (93) (94) (95). Unfortunately, these measures are neither easy to implement nor guaranteed to succeed.

Nevertheless, evidence linking urban form and transportation demand is compelling. Various studies suggest that in cities with relatively high residential densities and a balance of jobs and housing, people travel less, make shorter trips, and walk and bicycle more often. In the United Kingdom, for example, national survey data show that travel varies according to density. Travel demand quickly rises as density falls below 15 people per hectare and falls sharply as density exceeds 50 people per hectare (96). However, evidence is not sufficient to recommend an optimal density or settlement pattern. Comparative studies are generally limited by data constraints and confounding factors such as fuel prices, levels of automobile ownership, and cultural values (97).

Furthermore, textbook solutions rarely translate into real-life successes. London and Seoul, famous for their greenbelts, are facing new transportation challenges as urban development extends beyond those boundaries and workers commute even longer distances to downtown jobs (98) (99). In Delhi, India, mixed land uses and high population densities are the norm, yet the city is faced with congestion, air pollution, and limited transportation options for its poor people. (See Box 4.1.) Efforts to manipulate urban form are further complicated by issues of land ownership and market forces. Additionally, an integrated strategy requires coordination between the transportation and land use sectors across an entire metropolitan region--something that is not easily achieved (100) (101).

Still, cities that have managed to integrate transportation and land use are reaping the benefits. Curitiba, Brazil, is a notable example. By channeling urban growth along public transit routes, the city has managed to reduce privately owned car use, despite having the second highest per capita car ownership rate in Brazil (one car for every three people). On a typical workday, more than 70 percent of all commuters (1.3 million people) travel by bus. As a result, Curitiba's gasoline use per capita is 25 percent lower than that of eight comparable Brazilian cities, and the city has one of Brazil's lowest rates of ambient air pollution (102). Portland, Oregon, is using an integrated transportation and land use strategy in an attempt to head off the problems of sprawl and inner-city decay typical of many U.S. cities. (See Box 4.2.)

Full-Cost Pricing

One of the major factors contributing to urban transportation problems is that people do not pay for the full costs of their travel. Motorists rarely pay enough taxes to support the investments needed to construct and repair roads. Nor do car or gasoline prices reflect less tangible costs such as the negative health effects of automotive air pollution or productivity losses incurred by traffic delays.

These costs are substantial. At a national level in the United States, various studies suggest that motor vehicle use imposes on society estimated external costs of more than $300 billion (103) (104) (105). In urban areas, where negative impacts are concentrated, the cost per vehicle distance traveled is probably higher. Although much has been written in recent years about estimating the unpaid costs of travel, estimates of the full costs vary significantly, are subject to much dispute, and should be considered only rough approximations.

Moving toward recovering these costs would help to reduce uneconomical travel and would spread trips across longer periods of the day. These improvements could lead to a reduction in congestion, an increase in the use of public transit, and, perhaps in the long run, more efficient land use patterns (106). In OECD countries, raising the costs of car travel may be a more effective way to reduce car use and its related problems than improving public transportation service or lowering fares (107).

Although it is unlikely that drivers will ever pay the full costs of transportation by car, several policy tools can be used to at least recover some of these costs, ranging from road pricing to gasoline taxes, to increased fees for parking. These can be key elements in a strategy for managing travel demand.

Road Pricing.

Road pricing entails charging drivers directly for using roads through a variety of techniques, such as the use of tolls, area licensing schemes, and electronic road pricing. To be most effective, a road pricing scheme should cover all important roads throughout an urban area, and the charge should vary according to demand, with higher prices charged during peak periods, as is the case for electric utilities or telephone service. The goal is to encourage people to use alternate modes of transportation or to drive during off-peak periods.

Designing such a system, however, is complicated administratively, technically, and politically. In addition, road pricing will not succeed if cities do not offer attractive alternative transportation options (108). Accordingly, despite the demonstrated advantages of road pricing, few cities have implemented such schemes.

Most practical applications have been a type of area pricing, in which drivers must pay to enter a specific area. Perhaps the most well-known of these is Singapore's area licensing scheme, which seeks to reduce traffic into the city center by charging low-occupancy vehicles a fee when they enter the area. To enter the restricted area, a car must display a special window sticker, for which a fee is also charged. Since its inception in 1975, the plan has both reduced congestion and stimulated the use of public transportation, at modest cost. The city is replacing the current system with an electronic scheme. Cameras mounted on overhead gateways will automatically deduct entry fees from stored value cards mounted on vehicle dashboards. The fee will be determined by both location and time of day (109).

In OECD countries, road pricing is being considered seriously, although in most places it is still only in the testing phase. A "smart" card, which automatically imposes a charge when a vehicle is stalled in traffic, is being tried in Cambridge, United Kingdom, to reduce congestion (110). In the Norwegian cities of Oslo, Bergen, and Trondheim, electronic toll-collecting systems (initially designed to raise revenue for new road construction)may have the added benefit of reducing traffic in the city center (111).

In the developing world, the widespread introduction of electronic road pricing may not be feasible because of both the up-front costs of the technology and the potential difficulty of enforcement. Yet, road pricing can be cost effective--particularly in middle-income cities of the developing world, where motor vehicle use is increasing rapidly--because it can offset or delay costly expansion of the road system. Government officials in Santiago, Chile, are planning to implement a road pricing scheme (112).

Road pricing can have unintended impacts, however. For instance, it runs the risk of encouraging travel on roads on which a fee is not required, increasing congestion there and precipitating urban growth in new suburban areas. Road pricing must be examined for its equity impacts as well. By raising the price of travel, peak period pricing may squeeze poorer drivers off the road while allowing those who can afford it to drive on a more efficient road system. In San Francisco, the Bay Bridge Congestion Pricing pilot project proposed a way to overcome this problem by using existing low-income targeting mechanisms (in this case, an electric utility program that offers rebates to the poor) to provide discounts for poorer drivers (113). Alternatively, the funds generated could be used to reduce transit fares and improve transit service in low-income areas. Taxes and Pollution Fees. In addition to road pricing, other variable transportation charges to recover the full costs of transportation have been suggested. In practice, there is already an array of taxes on motor vehicles in most countries, ranging from purchase taxes on new vehicles to fuel taxes. Governments have long used fuel taxes as a means of raising revenue for road building and maintenance. Recently, however, some countries have begun to consider taxation as a means to reduce vehicle use, conserve energy, and reduce carbon dioxide emissions (114). Hungary, for instance, introduced an environmental tax on fuel in 1992 as well as a road maintenance fee (115).

Fuel taxes can be an important policy tool in efforts to change travel behaviors. The direct impact of fuel prices on the level and pattern of transportation demand has been vividly illustrated over the past 20 years by the effects of increases in world oil prices on the overall volume of transport, on the search for improved efficiencies in the use of traditional fuel sources, and on the development of alternative fuel technologies (116). The high cost of fuel in Japan and Europe has led people in those countries to drive less and to drive more fuel-efficient cars than their counterparts in the United States (117). Reducing fuel subsidies and increasing fuel taxes could help improve vehicle efficiencies in developing countries as well (118).

Pollution fees, which increase with the amount of pollution produced by a vehicle, or vehicle-miles-of-travel (VMT) fees also can be used to recover some of the true costs of car transportation. Such fees can be collected at annual vehicle inspections and can be based on odometer readings. Research suggests that a VMT fee of $0.03 per kilometer imposed in Southern California could reduce automobile trips and automotive air pollution by an estimated 11 percent and could increase public transit ridership (119).

Objections to higher taxes and fees are numerous. One concern is that they would hurt low-income families, who already spend proportionately more of their income on transportation. In addition, taxes do not influence when a car is used, so they may have little effect on congestion. Some analysts suggest that fuel taxes may become less effective in reducing travel demand as cars become more fuelefficient. However, the major barrier to implementation is political opposition. People tend to view these measures simply as additional unwelcome taxes. Overcoming this barrier will require educating the public about the full costs of their current travel decisions, as well as about how the new revenues will be used to improve the urban transportation system ertain areas can also deter the use of privately owned cars. If high parking costs raise the price of commuting to work, for example, workers will be more inclined to look for cheaper alternatives, either in the form of public transportation or carpooling.

This is especially true in the United States, where parking has traditionally been heavily subsidized. In downtown Los Angeles, for example, employer-paid parking increases drive-alone commuting by an estimated 44 percent. It also increases the total distance traveled as well as fuel consumption by 33 percent per employee (120). If, instead, employers were to offer workers a commuter stipend that could be used on any travel alternative in lieu of free or reduced-cost parking, one study found that drive-alone commuting would decrease by an estimated 20 percent and vehicle distance traveled would decrease by 17 percent (121).

Higher parking prices, however, can have the unintended effects of increasing illegal parking or increasing the length of trips (e.g., the additional time spent looking for parking places), thereby worsening congestion. Parking controls are most effective when they are used as part of a more comprehensive program and when strict enforcement is possible (122).

Traffic Bans

Instead of pricing signals, many cities have tried to use outright traffic bans to manage travel demand. Bans in the form of license number restrictions have been tried in Athens, Mexico City, and Santiago as a means of reducing the number of cars in the city and thereby reducing congestion and air pollution (123). Although these bans have been somewhat effective, many households bought a second car or switched license plates to meet their mobility needs. In Athens, the number of households with two cars increased, and motorists who were not allowed to enter the city center drove around the city to get to their destination, thereby increasing the length of their trips while also increasing emissions (124). In addition, the cars bought for use on off-days are often cheap, second-hand vehicles, which tend to be more polluting (125).

References and Notes

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