Indeed, in addition to the congestion problem, the steady rise in the number of vehicles has created substantial excesses in travel times above the normal. Based on simulation studies, the U. S. Federal Highway Administration has predicted that total traffic delay in 2008 will be five times that of the late 1980s. Across the United States, the average duration of a one-way commute is 24 minutes. But the standard deviation, or measure of variance, is 30. 4 minutes, which indicates that commutes vary widely and can in fact take twice as long as the average.
Japan, a more urban country than the United States, has experienced a large increase in commuting time over the last two decades despite its more extensive urban commuting systems. No matter the length of the commute, it is important to reduce travel time dispersion because unexpected and excessive delays are especially disruptive and too early arrivals are generally not helpful. Improving travel time is a major goal for most motorists, and they may be willing to pay extra to gain time.
The three main categories of ITS (traffic management systems, traveler information systems, and vehicle control systems) have the potential to improve traffic flow, diminish congestion, and help people avoid major delays from incidents, thereby substantially increasing the throughput and efficiency of our roadways. These systems will increase the volume of people and goods that can be moved on our highways and will reduce the need for building new roads.
Traffic management systems could reduce travel times by 10-15 percent ( Mobility 2000 1990). Highway surveillance and incident management on freeways could reduce total delay by 35 percent and reduce by 10 percent the more than 700 million hours of delay caused by recurring congestion. This would offer a delay savings of 525 million vehicle hours annually. The impact of ITS may be even higher in urban areas because of the more intense congestion problems there.
Reducing congestion would have a vast ripple effect in additional benefits for both individuals and industry, according to Mobility 2000 (1990). Reducing congestion would help to reduce travel time, fuel consumption, emissions, vehicle operating costs, driver and passenger stress, unpredictability of arrival time, emergency response time, noise pollution, shipping costs, transportation and equipment costs, and fleet management costs. Deviations from average travel times could be minimized with ITS technology.
Certain ITS implementations have particularly strong potential for congestion relief. (1) If demand management techniques, including congestion pricing, lead to the removal of one car in ten, it would reduce total delay time by 48 percent. Furthermore, demand for roads at peak times would be reduced, and the cost of using them would be distributed directly to the user. (2) Automated toll collection will relieve congestion at toll plazas, a typical trouble area.
(3) Dynamic route guidance will discourage additional vehicles from driving toward crowded roads and, in addition, improve travel time and better distribute traffic throughout the roadway system, thereby effectively increasing its capacity. Route guidance would also help to eliminate the 6 percent of all driving in the United States that results from incorrect choice of route. Overall reduction in congestion and delay will clearly be a function of the amount of penetration of route guidance technology within the vehicle population and the extent to which drivers follow the route guidance advice.
However, one estimate projects that route guidance in a hypothetical congested network could reduce the total travel time to all motorists by approximately 20 percent, assuming only 20 percent of drivers had such systems. ITS can lead to the development of shared ride services, which in turn can improve average vehicle occupancy. Then other ITS techniques such as preferential route guidance, automatic reduced tolls, and platooning can be applied to high-occupancy vehicles to gain the maximum results for the most people.
The longest-term perspective for platooning, whereby suitably equipped vehicles are electronically linked into groups that travel as a unit on dedicated instrumented lanes, envisions that as much as 200 to 300 percent more traffic will be handled. Considering the large number of traffic fatalities, commensurately larger number of injuries, and the great amount of property damage, improvements in safety are among the most important benefits to be derived from ITS. As ITS are gradually deployed, safety improvements have been estimated to be as follows: a 0.
17 percent reduction in fatalities by 1995, a 1. 7 percent reduction by 2000, and an 18. 9 percent reduction by 2010 ( Mobility 2000 1990). Also by 2010, the Mobility 2000 organization estimated, approximately 11,500 lives will be saved, 442,000 injuries prevented, and $22 billion in accident costs saved per year as a result of ITS implementation. Safety will also be increased through traffic management and traveler information systems that warn drivers of incidents and blockages ahead; this will soften the propagating traffic shock wave caused by abrupt deceleration.
According to the Vehicle Navigation and Information Systems Conference’s Record of Papers ( VNIS 1989), a study in France evaluated fourteen driver information systems in terms of potential effectiveness in avoiding accidents by using 350 carefully documented police accident reports. The activities and devices evaluated included intersection control, cooperative detection, anticollision, speed keeping, electronic vision, monitoring of driver condition, active rear-view mirror, navigation aids, car following, and vehicle overtaking.
The study found that up to 16 percent of accidents could be avoided through the use of these techniques. In other areas, imaging systems will promote safety by giving a clearer picture of road conditions. Navigation aids in conjunction with route guidance will help prevent drivers from getting lost, which is a safety gain because lost drivers often make erratic movements and cause accidents. Collision warning systems, which alert the driver of critical situations, will reduce traffic accidents, fatalities, and damage and relieve some of the stress of driving.
Older drivers, the fastest-growing segment of the population, will benefit from technologies such as heads-up displays that provide information at eye level and don’t require the drivers to take their eyes off the road. Vehicle control systems, which enhance or automate some of the driving function and eliminate much of the unpredictability of human judgment and reaction, have the potential to vastly improve safety when they are fully deployed.
Finally, electronic monitoring of the physical infrastructure would give early warning of unsafe bridges and tunnels. The loss of life associated with collapsed bridges and elevated highways would thus be avoided. A country’s ability to compete in the world marketplace depends on its ability to move people and products quickly, safely, and inexpensively. The efficiency of a country’s highway system is a major factor in this regard; national economies can be aggravated or ameliorated by losses or gains in the efficiency of the transportation system.
In the United States, the industry that supports this mobility constitutes a significant portion of the national economy. Approximately one-sixth of all businesses and one-seventh of all workers are in automobile, truck, and highway construction industries; and more than half of the top fifteen Fortune 500 corporations are automobile, petroleum, or steel companies. The economic impact of travel can be assessed in terms of productivity as well.
According to researchers at the University of Michigan (Chen and Ervin 1990), approximately $750 billion in time resources is devoted to travel in the United States each year. In terms of traffic delay alone, the expense in the United States in 1990 was approximately $100 billion in lost wages and direct costs. Preliminary research on ITS indicates that it is possible to achieve overall savings in the range of 10 percent by implementing the technology, indicating a potential annual savings of roughly $75 billion.
Proportional savings can be expected in Europe and Japan. Economic benefits from the application of information technology to the roadway system are important to all participants and users, especially public-sector organizations, which suffer from a chronic shortage of funds. Although implementing new technology in a public infrastructure could be thought to aggravate federal budget deficits, ITS might help reduce them in the long run by lessening the need to construct more highways or alternative transportation systems. In this regard, the U.
S. General Accounting Office analyzed twenty-three studies that researched the economic benefits of ITS (1991). Estimates of various costs and benefits that could occur through implementation of traffic management or traveler information systems showed future benefit-cost ratios of up to 10:1, indicating attractive returns. Where particularly bad inefficiencies exist, the ratio can be much higher initially but is likely to stabilize once the inefficiency has been corrected. Specific ITS are expected to create economic gains.
The simpler forms of ITS, such as traffic management centers and ramp metering, can decrease congestion by 15 percent at a value of $1. 2 billion (Mobility 2000 1990). Thirty-nine large cities in the United States have congestion costs of greater than $41 billion, and fully deployed ITS can produce congestion decreases ranging from 15 to 40 percent, indicating strong economic potential. In addition, congestion relief is expected to provide a savings of 10 to 50 percent in vehicle fuel costs, depending on individual engine sizes.
Automatic toll collection will lead to economic gain by introducing the ability to charge vehicles custom tolls and by eliminating the congestion around toll booths. Variable tolls can be a new source of highway funding; they also redistribute costs to users and provide a measure of the public’s acceptance of such projects. Other processes such as automatic vehicle location (AVL) systems make possible just-in-time delivery, custom routing, and efficient fleet management, which eases the cost of regulating road users and creates new income.
Still other economic benefits will likely follow the implementation of ITS. For example, insurance rates may be reduced. As devices that assist the driver become available, reduced numbers of accidents should promote lower insurance rates, especially for liability. Insurance companies might encourage the installation of such devices by offering lower rates to users. For another example, businesses that serve travelers will gain economically from ITS because of the increased available exposure to customers through traveler information systems.
New categories of businesses serving people on the move are also likely to be created. Electronic monitoring of the physical infrastructure should lead to significant cost savings as well as improved safety. The early warning provided by the monitoring network would allow problems to be corrected at an early stage; this would prevent them from developing into major problems that involve expensive, large-scale repairs or–in extreme cases–loss of use of the infrastructure altogether, as when a bridge or elevated highway collapses.
National economies as a whole can gain from the implementation of ITS, because the benefits and commercial opportunities offered by an informationbased transportation infrastructure are immense. One study by the Federal Highway Administration examined a range of industry and government estimates and integrated them to arrive at an overall estimate of $300 billion in highway inefficiency in the United States. The study also found other nonquantifiable costs such as environmental impacts.
Among the important quantifiable components of the inefficiency were $100 billion per year in lost time owing to road congestion, $70 billion per year in accidents, and $60 billion per year in navigation waste, which includes time, gasoline, and wear and tear because of poor routing. Although much more work needs to be done to quantify the benefits of particular aspects of ITS, there is considerable evidence that annual savings in the range of 15-25 percent are realistic within a reasonable time frame. Of course, the benefits must be set against the deployment costs for ITS.
ITS America, the focal organization for ITS development in the United States, estimates long-term deployment costs of the infrastructure to be approximately $40 billion and in-vehicle consumer costs to be approximately $170 billion over a twenty-year period (IVHS America 1991). In considering the benefits of reduced highway inefficiency, it is noteworthy that half of the benefits appear to relate to commercial vehicles. It is quite likely that these benefits can be achieved with less than half the total expenditures planned for ITS. However, the majority of planned ITS expenditure is for passenger vehicles.
Thus, a redirection of funds toward commercial vehicles–and, hence, away from passenger cars–would likely produce a higher ratio of benefits to investment. In particular, it might make sense to consider an automated lane for commercial vehicles rather than automating all lanes and equipping all vehicles.
Reference: Chen Kan, and Robert D. Ervin. 1990. “American Policy Issues in Intelligent Vehicle/Highway Systems. ” Ann Arbor: University of Michigan. IVHS America. 1991. Strategic Plan for IVHS in the U. S. Draft B. Washington, DC: IVHS America (now ITS America).