The Congestion Mitigation and Air Quality Improvement (CMAQ) program was enacted as part of the surface transportation legislation. This work recommends that Congress retain the sole federal surface transportation program that funds projects to reduce pollution and traffic congestion in areas that must comply with national air quality standards.
The Congestion Mitigation and Air Quality Improvement (CMAQ) program was enacted as part of the surface transportation legislation. This work recommends that Congress retain the sole federal surface transportation program that funds projects to reduce pollution and traffic congestion in areas that must comply with national air quality standards.
In light of recent evidence on the relationship of ozone to mortality and questions about its implications for benefit analysis, the Environmental Protection Agency asked the National Research Council to establish a committee of experts to evaluate independently the contributions of recent epidemiologic studies to understanding the size of the ozone-mortality effect in the context of benefit analysis. The committee was also asked to assess methods for estimating how much a reduction in short-term exposure to ozone would reduce premature deaths, to assess methods for estimating associated increases in life expectancy, and to assess methods for estimating the monetary value of the reduced risk of premature death and increased life expectancy in the context of health-benefits analysis. Estimating Mortality Risk Reduction and Economic Benefits from Controlling Ozone Air Pollution details the committee's findings and posits several recommendations to address these issues.
TRB Special Report 288, Metropolitan Travel Forecasting: Current Practice and Future Direction, examines metropolitan travel forecasting models that provide public officials with information to inform decisions on major transportation system investments and policies. The report explores what improvements may be needed to the models and how federal, state, and local agencies can achieve them. According to the committee that produced the report, travel forecasting models in current use are not adequate for many of today's necessary planning and regulatory uses.
Various combinations of commercially available technologies could greatly reduce fuel consumption in passenger cars, sport-utility vehicles, minivans, and other light-duty vehicles without compromising vehicle performance or safety. Assessment of Technologies for Improving Light Duty Vehicle Fuel Economy estimates the potential fuel savings and costs to consumers of available technology combinations for three types of engines: spark-ignition gasoline, compression-ignition diesel, and hybrid. According to its estimates, adopting the full combination of improved technologies in medium and large cars and pickup trucks with spark-ignition engines could reduce fuel consumption by 29 percent at an additional cost of $2,200 to the consumer. Replacing spark-ignition engines with diesel engines and components would yield fuel savings of about 37 percent at an added cost of approximately $5,900 per vehicle, and replacing spark-ignition engines with hybrid engines and components would reduce fuel consumption by 43 percent at an increase of $6,000 per vehicle. The book focuses on fuel consumption-the amount of fuel consumed in a given driving distance-because energy savings are directly related to the amount of fuel used. In contrast, fuel economy measures how far a vehicle will travel with a gallon of fuel. Because fuel consumption data indicate money saved on fuel purchases and reductions in carbon dioxide emissions, the book finds that vehicle stickers should provide consumers with fuel consumption data in addition to fuel economy information.
Emissions inspection and maintenance (I/M) programs subject vehicles to periodic inspections of their emission control systems. Despite widespread use of these programs in air-quality management, policy makers and the public have found a number of problems associated with them. Prominent among these issues is the perception that emissions benefits and other impacts of I/M programs have not been evaluated adequately. Evaluating Vehicle Emissions Inspection and Maintenance Programs assesses the effectiveness of these programs for reducing mobile source emissions. In this report, the committee evaluates the differences in the characteristics of motor vehicle emissions in areas with and without I/M programs, identifies criteria and methodologies for their evaluation, and recommends improvements to the programs. Most useful of all, this book will help summarize the observed benefits of these programs and how they can be redirected in the future to increase their effectiveness.
Emissions from mobile sources contribute significantly to air pollution in the United States. Such sources include cars and light- and heavy-duty trucks; diesel-powered cranes, bulldozers, and tractors; and equipment such as lawnmowers that run on small gasoline engines. The role of state versus federal government in establishing mobile-source emissions standards is an important environmental management issue. With this in mind, Congress called on EPA to arrange an independent study of the practices and procedures by which California develops separate emissions standards from the federal government and other states choose to adopt the California standards. The report provides an assessment of the scientific and technical procedures used by states to develop or adopt different emissions standards and a comparison of those policies and practices with those used by EPA. It also considers the impacts of state emissions standards on various factors including compliance costs and emissions. The report concludes that, despite the substantial progress in reducing emissions from mobile sources nationwide, more needs to be done to attain federal air-quality standards in many parts of the country. Additionally, California should continue its pioneering role in setting emissions standards for cars, trucks, and off-road equipment.
All phases of road developmentâ€"from construction and use by vehicles to maintenanceâ€"affect physical and chemical soil conditions, water flow, and air and water quality, as well as plants and animals. Roads and traffic can alter wildlife habitat, cause vehicle-related mortality, impede animal migration, and disperse nonnative pest species of plants and animals. Integrating environmental considerations into all phases of transportation is an important, evolving process. The increasing awareness of environmental issues has made road development more complex and controversial. Over the past two decades, the Federal Highway Administration and state transportation agencies have increasingly recognized the importance of the effects of transportation on the natural environment. This report provides guidance on ways to reconcile the different goals of road development and environmental conservation. It identifies the ecological effects of roads that can be evaluated in the planning, design, construction, and maintenance of roads and offers several recommendations to help better understand and manage ecological impacts of paved roads.
TRB Special Report 302: Federal Funding of Transportation Improvements in BRAC Cases explores federal funding of transportation improvements in Defense Base Closure and Realignment Commission (BRAC) cases. The committee that produced the report concluded that traffic delays resulting from the BRAC decisions and short timeline for implementing the decisions will impose substantial costs on surrounding communities and may even be harmful to the military.
The Mobile Source Emissions Factor (MOBILE) model is a computer model developed by the U.S. Environmental Protection Agency (EPA) for estimating emissions from on-road motor vehicles. MOBILE is used in air-quality planning and regulation for estimating emissions of carbon monoxide (CO), volatile organic compounds (VOCs), and nitrogen oxides (NOx) and for predicting the effects of emissions-reduction programs. Because of its important role in air-quality management, the accuracy of MOBILE is critical. Possible consequences of inaccurately characterizing motor-vehicle emissions include the implementation of insufficient controls that endanger the environment and public health or the implementation of ineffective policies that impose excessive control costs. Billions of dollars per year in transportation funding are linked to air-quality attainment plans, which rely on estimates of mobile-source emissions. Transportation infrastructure decisions are also affected by emissions estimates from MOBILE. In response to a request from Congress, the National Research Council established the Committee to Review EPA's Mobile Source Emissions Factor (MOBILE) Model in October 1998. The committee was charged to evaluate MOBILE and to develop recommendations for improving the model.
Includes the proceedings of a conference to advise the United States Department of Transportation, the community at large, and state and local elected officials on the appropriate planning and decision-making process needed to select and develop projects that will improve urban mobility, with emphasis on efficiency, concern for the environment, and shared responsibilities among agencies and affected groups, all within the context of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) and the Clean Air Act Amendments of 1990 (CAAA).
The U.S. census, conducted every 10 years since 1790, faces dramatic new challenges as the country begins its third century. Critics of the 1990 census cited problems of increasingly high costs, continued racial differences in counting the population, and declining public confidence. This volume provides a major review of the traditional U.S. census. Starting from the most basic questions of how data are used and whether they are needed, the volume examines the data that future censuses should provide. It evaluates several radical proposals that have been made for changing the census, as well as other proposals for redesigning the year 2000 census. The book also considers in detail the much-criticized long form, the role of race and ethnic data, and the need for and ways to obtain small-area data between censuses.
Reviews how current flexible funding provisions are being used to support transit investment and examines lessons that may have the broadest relevance throughout the transit industry. The scope of the synthesis includes references to summary FTA data from FY 1992-2000, spanning the entire life of the ISTEA legislation and the first 3 years of TEA-21.
The Federal Highway Administration and Federal Transit Administration requested that the Transportation Research Board and the Commission on Behavioral and Social Sciences and Education of the National Research Council conduct a study of congestion pricing for congestion management. To conduct this study, the National Research Council established the Committee for Study on Urban Transportation Congestion Pricing. The committee's deliberations were supplemented by liaison representatives from several groups concerned about the benefits and costs of congestion pricing. After a review of the literature, and drawing from its expertise, the committee commissioned papers on a variety of topics. Volume 1 contains the committee's overview of the material contained in the commissioned papers, its conclusions, and its recommendations regarding the potential of congestion pricing, the need for evaluation of early demonstrations, and other research needs. Volume 2 provides a rich array of information about individual case studies from around the nation and thoughtful analyses by individual scholars about many of the critical issues surrounding congestion pricing., as revised by their authors after the symposium.
Recognizes the importance of freight transportation to the US and that intermodal freight transportation is a major technological and organizational trend affecting the sector's performance. Examining policy options, this report views that public investment in freight facilities is complex and they have been usually financed by the private sector.
The conference on Setting an Intermodal Research Framework brought together a distinguished assembly of public officials, academicians, commercial leaders, and military specialists. During the conference, each of these groups of professionals found noteworthy synergies in their intermodal interests. Papers contained in these proceedings reflect those synergies. The conference was another step toward a strengthened intermodal partnership.
This synthesis will be of interest to officials of municipal, regional, and statewide transportation agencies who are responsible for the management of surface transportation systems in metropolitan areas. It presents information on the processes used by transportation agencies to monitor, evaluate, and implement a variety of solutions to the management of surface transportation systems. This is a complex and dynamic area of application, and the examples presented herein represent a selection of such applications in 1997. The concept of transportation system management is constantly changing and will continue to change, especially with further implementation of intelligent transportation systems. This report of the Transportation Research Board provides an overview of the generalized process that transportation agencies have found to be effective in managing the various aspects of their transportation systems. Specific case examples of effective management strategies are described for several metropolitan areas including Houston, Seattle, metropolitan New York, Los Angeles, San Francisco, and Minneapolis/St. Paul.
Two conferences on Refocusing Transportation Planning for the 21st Century were held in 1999 following passage of the Transportation Equity Act for the 21st Century (TEA-21). The first conference focused on the identification of key trends, issues, and general areas of research. The results of Conference I, which produced stand-alone products, were used as input for Conference II. The second conference had the specific objective of producing research problem statements. Its mission was to review the results of the first conference by developing these statements. Conference II produced a number of detailed research statements that form the basis for the National Agenda for Transportation Planning Research. The proceedings of both conferences are presented in this report.
These proceedings document the second Conference on Decennial Census Data for Transportation Planning to be held since the 1990 census. It is the fifth in a series of related conferences (1970, 1973, 1984, and 1994). Volume 1, contains the following: Introductory Remarks, C.L. Purvis; Summary and Recommendations, A.E. Pisarski; Opening Session presentations (3); Summary of Case Studies on Uses of 1990 Census Data (5); Plenary Sessions (3); Workshop Reports (2); an Appendix containing Facsimiles of the Journey-to-Work Questions; and a list of conference participants. Volume 2, contains most of the case studies, organized into the following areas: Large Metropolitan Areas; Transit; Private Sector; Small Metropolitan Areas; and State Departments of Transportation.
Technologies and Approaches to Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles evaluates various technologies and methods that could improve the fuel economy of medium- and heavy-duty vehicles, such as tractor-trailers, transit buses, and work trucks. The book also recommends approaches that federal agencies could use to regulate these vehicles' fuel consumption. Currently there are no fuel consumption standards for such vehicles, which account for about 26 percent of the transportation fuel used in the U.S. The miles-per-gallon measure used to regulate the fuel economy of passenger cars. is not appropriate for medium- and heavy-duty vehicles, which are designed above all to carry loads efficiently. Instead, any regulation of medium- and heavy-duty vehicles should use a metric that reflects the efficiency with which a vehicle moves goods or passengers, such as gallons per ton-mile, a unit that reflects the amount of fuel a vehicle would use to carry a ton of goods one mile. This is called load-specific fuel consumption (LSFC). The book estimates the improvements that various technologies could achieve over the next decade in seven vehicle types. For example, using advanced diesel engines in tractor-trailers could lower their fuel consumption by up to 20 percent by 2020, and improved aerodynamics could yield an 11 percent reduction. Hybrid powertrains could lower the fuel consumption of vehicles that stop frequently, such as garbage trucks and transit buses, by as much 35 percent in the same time frame.
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