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C O N F E R E N C E P R O C E E D I N G S 3 7

Integrating Sustainability into the TransportationPlanning Process

Committee for the Conference on Introducing Sustainability intoSurface Transportation Planning

Baltimore, MarylandJuly 11–13, 2004

Sponsored byTransportation Research BoardFederal Highway AdministrationU.S. Environmental Protection Agency

Washington, D.C. 2005

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Transportation Research Board Conference Proceedings 37ISSN 1073-1652ISBN 0-309-09418-6

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NOTICE: The conference that is the subject of this report was approved by the Governing Board of theNational Research Council, whose members are drawn from the councils of the National Academy ofSciences, the National Academy of Engineering, and the Institute of Medicine. The members of the com-mittee responsible for the report were chosen for their special competencies and with regard for appropri-ate balance.

This report has been reviewed by a group other than the authors according to the procedures approvedby a Report Review Committee consisting of members of the National Academy of Sciences, the NationalAcademy of Engineering, and the Institute of Medicine.

The views expressed in the presentations and papers contained in this report are those of the authors anddo not necessarily reflect the views of the committee, the Transportation Research Board, the NationalResearch Council, or the sponsors of the conference.

The conference was sponsored by the Transportation Research Board, the Federal HighwayAdministration of the U.S. Department of Transportation, and the U.S. Environmental Protection Agency.

Committee for the Conference on Introducing Sustainability into Surface Transportation PlanningDavid L. Greene, Oak Ridge National Laboratory, ChairWilliam R. Black, Indiana UniversityDavid G. Burwell, Prague Institute for Global Urban DevelopmentThomas M. Downs, Eno Transportation FoundationRichard Gilbert, Centre for Sustainable TransportationKevin E. Heanue, ConsultantYsela Llort, Florida Department of TransportationMarianne Millar Mintz, Argonne National LaboratoryArthur (Chris) Nelson, Virginia Polytechnic Institute at AlexandriaJohn P. Poorman, Capital District Transportation CommitteeDaniel Sperling, Institute of Transportation Studies, University of California at Davis

Liaison MembersMichael Savonis, Federal Highway AdministrationKirsten Oldenburg, Bureau of Transportation Statistics

Transportation Research Board StaffMark R. Norman, Director, Technical ActivitiesClaire L. Felbinger, Transportation Policy and Management SpecialistMartine Micozzi, Management and Policy SpecialistMary Kissi, Senior Program AssistantJanille Smith, National Research Council InternKarin DeMoors, TransTech Management, Inc., Consultant

TRB Publications Office StaffNorman Solomon, Senior EditorMary McLaughlin, ProofreaderJennifer J. Weeks, Editorial Services Specialist

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Contents

PREFACE ..................................................................................................................................................vii

COMMITTEE FINDINGS AND RECOMMENDATIONS..........................................................................................1

GENERAL AND CONCURRENT SESSIONS

Welcoming Remarks and Charge to the Conference ...............................................................................11Jim Shrouds and David L. Greene

Keynote Address .....................................................................................................................................12Thomas B. Deen

Presentations on Transportation Sustainability Indicators.......................................................................13Mark DeLuchi, Mike MacCracken, Daniel Sperling, David G. Burwell, Elizabeth Deakin, and Richard Forman

Concurrent Sessions: What Are the Challenges? .....................................................................................17William R. Black, Joan Ogden, Michael Wang, Kevin E. Heanue, Bob Johnston, John P. Poorman, Arthur (Chris) Nelson, Steve Lockwood, Tom Sanchez, Christina Casgar, Lee Schipper, and Martin Lee-Gosselin

Reports on the Concurrent Sessions: What Are the Challenges? .............................................................21Genevieve Giuliano, Thomas M. Downs, Anne Canby, and Richard Gilbert

Panel Discussion: Potential Solutions to Challenges ................................................................................24Kevin E. Heanue, Anne Canby, John Horsley, Hal Kassoff, John Pucher, and G. Alexander Taft

Reports on Concurrent Roundtable Discussions: Potential Solutions to Challenges................................26Genevieve Giuliano, Thomas M. Downs, Anne Canby, and Richard Gilbert

Luncheon Speakers..................................................................................................................................29Lewis Dale and Emil Frankel

Poster Session..........................................................................................................................................31

Conference Closing .................................................................................................................................32David L. Greene

RESOURCE PAPERS

Sustainable Transport: Definitions and Responses ..................................................................................35William R. Black

What Are the Challenges to Creating Sustainable Transportation? How Can Transportation Systems Become More Sustainable? ....................................................................................................44

Martin Wachs

COMMITTEE MEMBER BIOGRAPHICAL INFORMATION ..................................................................................53

PARTICIPANTS............................................................................................................................................58

v i i

Preface

In July 2004 approximately 70 people assembled inBaltimore, Maryland, to participate in the Confer-ence on Integrating Sustainability into the Trans-

portation Planning Process. The conference, organizedand conducted by the Transportation Research Board(TRB), brought together individuals from across thetransportation, energy, environmental, land use, plan-ning, and public policy communities—at national, state,and local levels and from the public and the private sec-tors. The public sector was represented by officials fromthe U.S. Department of Transportation, the FederalHighway Administration, the Federal Transit Adminis-tration, and the U.S. Environmental Protection Agencyas well as from state and regional organizations. Pri-vate-sector participants included members of academia,individuals from trade associations, automotive indus-try professionals, and consultants.

Sponsored by TRB, the Federal Highway Adminis-tration, and the U.S. Environmental Protection Agency,the conference was conducted under the auspices ofTRB’s parent organizaton, the National Research Coun-cil (NRC). A specially appointed NRC committee devel-oped the conference as a forum to exchange perspectiveson the challenges and potential solutions to the chal-lenges of integrating sustainability concerns into thetransportation planning process. Drawing on theresource papers, presentations, and conference discus-sions, the conference committee evaluated the currentstate of the practice, considered strategies for integrat-ing sustainability concepts into transportation planning,and identified areas for further research.

CONFERENCE PROGRAM

The conference program was designed to maximize theexchange of information and perspectives among par-ticipants. To gain a better understanding of all of theviewpoints presented, the reader is encouraged to readthe report in its entirety.

The program began with a general session (GeneralSession 1) that included a welcome from the FederalHighway Administration, a sponsor of the conference;the presentation of the conference charge by the confer-ence committee chair, David Greene; a keynote addressby Thomas Deen; and presentation of the first of tworesource papers developed for the conference—“Sus-tainable Transport: Definitions and Responses” byWilliam Black.

In General Session 2, participants heard from expertson six indicators of sustainability: health, climate change,energy, equity, land/community, and habitats/ecosystems.In General Session 3, the second resource paper was pre-sented—“What Are the Challenges to Creating Sustain-able Transportation? How Can Transportation SystemsBecome More Sustainable?” by Martin Wachs.

The conference program then separated the partici-pants into four concurrent panel sessions organized intosubstantive tracks. Each concurrent session included afacilitator who served to energize and spur discussionand a rapporteur who recapped the discussion high-lights. Concurrent Sessions I focused on the challengesof sustainable transportation, and Concurrent SessionsII requested the participants to discuss potential solu-

tions to the challenges. In General Sessions 4 and 6 therapporteurs provided summaries of the concurrent ses-sion discussions to stimulate the exchange of viewsamong conference participants.

In General Session 5 industry experts participated ona panel in which they presented approaches to the chal-lenges of sustainable transportation. In addition to thegeneral and concurrent sessions described above, theconference included two luncheon speakers and a postersession. By the close of the conference, participants notonly had collected a significant amount of informationbut also had exchanged perspectives.

ACKNOWLEDGMENTS

This report has been reviewed in draft form by individualschosen for their diverse perspectives and technical exper-tise, in accordance with procedures approved by NRC’sReport Review Committee. The purposes of this indepen-dent review are to provide candid and critical commentsthat will assist the institution in making its publishedreport as sound as possible and to ensure that the reportmeets institutional standards for objectivity, evidence, and

responsiveness to the study charge. The review commentsand draft manuscript remain confidential to protect theintegrity of the deliberative process.

The conference committee thanks the following indi-viduals for their review of this report: David J. Forken-brock, University of Iowa, Iowa City; Francis B.Francois, Consultant, Washington, D.C.; Charles E.Howard, Jr., Puget Sound Regional Council, Seattle,Washington; Ashby Johnson, Houston–Galveston AreaCouncil, Houston, Texas; Lee Schipper, World ResourcesInstitute, Washington, D.C.; and Sarah J. Siwek, Sarah J.Siwek and Associates, Inc., Los Angeles, California.

Although the reviewers listed above provided manyconstructive comments and suggestions, they were notasked to endorse the conclusions or recommendations,nor did they see the final draft of the report before itsrelease. The review of this report was overseen by C.Michael Walton, University of Texas at Austin. Appointedby NRC, he was responsible for making certain that anindependent examination of this report was carried out inaccordance with institutional procedures and that allreview comments were carefully considered. Responsibil-ity for the final content of this report rests entirely with theauthoring committee and the institution.

INTEGRATING SUSTAINABILITY INTO THE TRANSPORTATION PLANNING PROCESSv i i i

1

The idea of a sustainable society in which theneeds of the present are met without compro-mising the ability of future generations to meet

their own needs is compelling. Despite its many dimen-sions and uncertainties, sustainability is generallyagreed to be important and worth pursuing. At thesame time, current trends in transportation contributeto unsustainable conditions, including climate change,energy insecurity, congestion, noise pollution, and eco-logical impacts. Widespread uncertainty exists abouthow to address the goal of a sustainable transportationsystem. What is clear is that attaining a sustainabletransportation system will require action by the publicsector, private companies, and individual citizens.Given the complexity of the issue and the variety ofplayers, it also will require a major cultural change toraise and organize societal awareness.

The effort to form a culture in which sustainability con-cepts are legitimized and integrated into transportationplanning is just beginning and will likely involve a longlearning process. The Transportation Research Board(TRB) Conference on Integrating Sustainability into theTransportation Planning Process examined whether andhow sustainability objectives can be introduced into theplanning process for surface transportation facilities andoperations.

After the final conference session, the TRB Commit-tee for the Conference on Introducing Sustainability intoSurface Transportation Planning convened to developits findings, which were based largely on the presenta-

tions and discussions at the conference. A summary ofthe committee’s findings and recommendations follows.They are organized into four sections:

• Issues of sustainability,• Vision of a sustainable transportation system,• State of the practice, and• Strategies for integrating sustainability concepts

into transportation planning.

ISSUES OF SUSTAINABILITY

The concept of sustainability has a powerful grip onpeople. Few could disagree that attainment of a sustain-able transportation system is desirable; however, manychallenges lie along the path to achieving such a system.The nation’s transportation system has enhanced qual-ity of life through increased access to health care, edu-cation, employment, recreation, and a wide range ofconsumer goods. These benefits have not been achievedwithout costs. The negative impacts of the transporta-tion system include congestion; fatalities and injuries;noise, air, and water pollution; greenhouse gas emis-sions; diminishing energy resources; and biological andecosystem damage. The challenge of a sustainable trans-portation system lies in minimizing these costs whileoffering strong transportation benefits.

There have been some successes in responding tothese challenges. Air quality regulations, for instance,

Committee Findings and Recommendations

have resulted in substantial air quality improvements.Air pollution has not been eliminated, but air quality isbetter in most areas. This success and others provideencouragement that sustainable transportation chal-lenges can be met. However, consistent effort is neces-sary, even in areas where progress has been made. Airquality has improved, but increasing travel volumesrequire continuing reductions in air pollution.

Numerous unsustainable impacts of transportationdemonstrate the challenges faced in transitioning to asustainable transportation system. A discussion of theseimpacts is provided below.

Nonrenewable Fuel Depletion and Energy Insecurity

The current transportation system depends on nonrenew-able fuels. The rate of consumption of nonrenewable fuelsis projected to grow as travel domestically and elsewhereincreases. The challenge is in finding ways to reduce therate of consumption of nonrenewable energy sources—including more carbon-intense unconventional sources ofpetroleum—through the development of renewableenergy sources, improved energy efficiency of vehicles,and increased use of public and nonmotorized transporta-tion. There are economic, environmental, and societaltrade-offs associated with each of these alternatives.

Greenhouse Gas Emissions

The burning of fossil fuels to power transportation vehi-cles releases greenhouse gases into the atmosphere,which contributes to increasing global average tempera-ture and other climate changes. Greenhouse gases areemitted throughout the fuel cycle, from well to tailpipe.The use of petroleum-based fossil fuels for transporta-tion is responsible, directly or indirectly, for more thanone-fourth of U.S. emissions of carbon dioxide, the prin-cipal greenhouse gas produced by transportation.Improved fuel efficiency and increased use of alternativefuels are proven options available to reduce greenhousegas emissions over the entire fuel cycle.

Global Climate Change

An enhanced greenhouse effect will have significantimpacts on sea level, climate, and agriculture. Impactsof the rise in sea level alone may include the flooding oftunnels, coastal highways, runways, and railways.Other impacts may include grounding of airplanes dueto high temperatures, buckling of highways and rail-road tracks due to heat, the submersion of dock facili-

ties, and a shift in agriculture to areas that are nowcooler. Such results demonstrate that reducing green-house gas emissions must be a top priority. The extentof mitigation will mainly determine the rate of climatechange experienced by future generations. Because ofthe inertia of the climate system, adaptation will be nec-essary regardless of efforts to reduce greenhouse gasemissions from this time forward. It is probably too lateto prevent or completely reverse climate change.

Local Air Quality

Motorized vehicles contribute significantly to local airpollution. Poor air quality has various negative healthimpacts, particularly on the respiratory system. Airquality, however, is one area where large gains have beenmade. Growth in transportation activity threatens tolimit the effectiveness of existing strategies to reduceemissions. As a result, despite the progress that has beenmade, new methods, technologies, and policies toimprove air quality are required.

Fatalities and Injuries

Unacceptable levels of fatalities and injuries occur onthe nation’s highways. A goal of zero fatalities and seri-ous injuries is appropriate. Sustainability argues for acontinuous decline in fatalities and injuries resulting ina safer transportation system.

Congestion

Congestion would be a sustainability issue even if anenergy source were developed that had zero harmfulemissions and was renewable. Congestion worsensmotorized mobility. The rise in congestion is attribut-able not only to increased personal mobility and freightmovement but also to a lack of adequate and reliabletransportation funding. Congestion negatively affectsthe economic and social health of the nation and, if notaddressed, will leave future generations without a rea-sonable level of mobility. Some observers argue thatcongestion can have positive implications for sustain-ability because congested highways cause some peopleto choose alternative modes of transportation.

Noise Pollution

The transportation system is a significant source ofnoise. Transportation noise originates from all motor-ized modes of transport. Examples of transportation-

2 INTEGRATING SUSTAINABILITY INTO THE TRANSPORTATION PLANNING PROCESS

related sources of noise include engines, vehicle contactwith pavement and other surfaces, horns, construction,brakes, and airplane takeoff and landing, to name a few.Loud noise and continuous noise are harmful to humanhealth. The impacts include behavioral disorders, heartdisease, and hearing loss. Noise also disturbs wildlife.Studies of the breeding and habitat of birds have foundthat higher volumes of traffic affect the nesting patternsof birds. Noise harms human health and wildlife andcan damage the quality of life.

Low Mobility

A reasonable level of mobility is an essential character-istic of a sustainable transportation system. Mobility isnecessary for the nation’s economy and for social andcultural interaction. Transportation must be availableto all members of the community, including vulnerablegroups such as persons with low income, children, theelderly, and the disabled.

Ecosystem Damage

Transportation activities can harm biological resources.The effects can range from the death of individual animalsto the loss of critical habitat. Some impacts are localized,such as animals killed along highways, disruption ofmigration patterns, runoff that pollutes rivers and streams,oil tanker spills, and plants affected by emissions. Otherimpacts are more profound, such as fragmentation andloss of species and long-term damage to ecosystems.Improvements have been made with regard to the effectsof transportation on ecosystems. For example, mitigationrequirements for highways and other paved surfaces atairports, seaports, and maintenance garages have greatlyreduced runoff impacts. The Endangered Species Act hasprovided significant protections. As population and travelvolume increase, a continuous effort must be made tomaintain and improve on areas of success.

Lack of Equity

Intergenerational and social equity are the overarchingaims of a sustainable transportation system. In reducingthe unsustainable impacts of transportation, as dis-cussed elsewhere in this section, progress toward anequitable transportation system would be made.

The challenges to achieving a sustainable transporta-tion system identified above provide a baseline for anaction agenda that can lead to a sustainable transporta-tion system. Properly planned transportation systemscan play a central role in promoting sustainability.

VISION OF A SUSTAINABLETRANSPORTATION SYSTEM

What would a sustainable transportation system looklike? Outlining the basic components of such a system isan important step in progressing toward sustainability,even if the resulting vision is not entirely clear.

At the most basic level, a sustainable transportationsystem is one that meets the transportation and otherneeds of the present without compromising the ability offuture generations to meet their needs. In considering theneeds of future generations, however, the benefits of thepresent transportation system should not be excessivelyinhibited or used as the justification for precluding futurechoices. Transportation planners and providers mustcontinuously struggle with the trade-offs between theeconomic and societal benefits of transportation and theassociated unsustainable environmental, safety, health,ecosystem, and equity impacts.

A sustainable transportation system requires a cul-ture that not only sees sustainability as desirable butalso accepts the inclusion of sustainability concepts inthe transportation planning process and supports thetough decisions necessary to make sustainability a pri-ority. The public and policy makers in this culture willunderstand and consider potential solutions, such asintegrated land use and transportation and innovativepublic transportation (for example, bus rapid transitand car sharing).

This cultural acceptance will be supported by theprovision of adequate and reliable transportation fund-ing consistent with fiscal constraints. Legislators andpolicy makers will recognize that a sustainable fundingsource is needed to meet current mobility needs whileaddressing the unsustainable effects of transportation.In addition, transportation providers must be able toensure that investments in transportation facilities haveadequate operations and maintenance funding.

A sustainable transportation system will have account-ability in the planning process. Performance measure-ment and feedback loops will enable planners to learnfrom past experiences and understand fully the ramifica-tions of decisions on the components of sustainability.Continuous improvement enabled through flexibility andinnovation will be a key element of sustainable trans-portation as travel patterns, vehicle and fuel technologies,land use patterns, population densities, and individualtravel choices change.

STATE OF THE PRACTICE

On the basis of the ideas and issues addressed at theconference (and summarized elsewhere in these pro-ceedings), the committee developed a set of observa-

3COMMITTEE FINDINGS AND RECOMMENDATIONS

tions about the state of the practice with regard to sus-tainability concepts and transportation. These are orga-nized into two categories: (a) political, legislative, andregulatory findings and (b) transportation planningprocess findings.

Political, Legislative, and Regulatory Findings

Lack of a National Sustainable Transportation Policy

There is no effective national policy with regard to thesustainability of transportation. A national policy onthe need to integrate sustainability concepts into trans-portation planning could facilitate the development oflegislation, regulation, guidance, and other tools. Thenew tools would support changes in current practicesthat are unacceptable because they fail to emphasize orignore notions of sustainability.

Innovative Solutions Often Discouraged byCurrent Standards and Regulations

Innovative transportation solutions that could addresssustainability issues are often discouraged by inflexibleand outdated regulations, rules, codes, and standards.Examples of such innovative solutions are improved fueleconomy standards, full-cost pricing, certain transporta-tion infrastructure and vehicle technologies, and alterna-tive energy sources and fuels. Flexibility must be providedto enable minimization of adverse sustainability impacts.

Transportation Planning Process Findings

Transportation Planning Horizons Not Long Enough

Federal regulations relating to transportation and air qual-ity require states and metropolitan planning organizationsto complete long-range transportation plans and pro-grams for a 20-year forecast period. For transportationplanning processes to integrate sustainability objectives,the forecast period must be at least 40 years. Some plan-ning organizations have begun to extend their planninghorizons, but the practice remains limited.

Assessment of Transportation Impacts NotSufficiently Broad

The effects of transportation on climate change are notusually considered in the planning process. In certain

areas, such as road ecology, some effects are considered,such as the presence of endangered species in theplanned corridor. Other effects, however, such as theimpacts of noise on the breeding and migration patternsof birds, are not commonly considered. A more coher-ent and integrated road ecology approach is needed.Transportation planning, particularly in urban areas, isbased on already adopted land use plans and objectives.Integrated transportation and land use decision makinghas not been realized. Land use planning and zoningremain the prerogative of local governments that striveto optimize their own objectives, which often directlyrelate to maximizing local tax revenue. Planningprocesses also do not give appropriate importance tothe role of freight and its impact on sustainability.

Existing Institutional Structure PermitsIntegrating Sustainability into Planning

Sustainability objectives can be introduced into the trans-portation planning process within the current institu-tional structure. State departments of transportation andmetropolitan planning organizations, for example, arecapable of incorporating sustainability into their plan-ning processes. Indeed, sustainability practices and toolsdo exist and are utilized by some states and planningorganizations, but not widely. The barriers to implement-ing sustainable transportation planning within currentorganizations are more cultural than institutional.

STRATEGIES FOR INTEGRATING SUSTAINABILITYCONCEPTS INTO TRANSPORTATION PLANNING

In line with its findings, the committee developed a setof recommendations focused on updating and improv-ing the planning process, providing public and profes-sional education, and identifying areas for furtherresearch. Given the complexity and scale of the sustain-ability challenge, the committee first pointed to threeareas where broadly based action is needed to achievegreater coherence and consensus on sustainability, bothnationally and internationally:

• Adopting a national statement of values and defi-nitions on sustainability, including a transportation com-ponent with specific national objectives and performancemeasures that can support review and revision of theobjectives. Possible objectives include the reduction ofgreenhouse gas emissions from transportation sourcesvia energy efficiency, reduction in the use of nonrenew-able transportation fuels, and support of nontechnologi-cal solutions such as incentives for use of nonmotorizedtransport and public transportation.


• Building consensus on a sustainability policy acrossall levels of government—federal, state, regional, andlocal. To lead effectively in communication and consensus-building activities across relevant agencies at all levelsof government, the U.S. Department of Transportationwill need to determine how to bring about this collab-oration and how best to support the efforts of localgovernments to tackle transportation sustainability.

• Cooperating with other nations to address theglobal dimensions of sustainable transportation. Withimpacts that are global as well as local and regional, thisinherently international issue requires that the UnitedStates work cooperatively with other nations to addresssustainable transportation effectively.

The committee made the following recommendationsfor integrating sustainability concepts into transportationplanning.

Planning Process Recommendations

Adopt Sustainability as a Primary Objective of Transportation Planning

At all levels of government—federal, regional, state, andlocal—use of sustainability criteria should be a centralfeature of transportation planning. A goal of trans-portation planning should be to address transporta-tion’s unsustainable impacts, including depletion ofnonrenewable fuels, climate change, air pollution, fatal-ities and injuries, congestion, noise pollution, lowmobility, biological damage, and lack of equity. Thesecriteria should be built into planning guidelines andprocesses. In addition, transportation planning shouldbe proactive and promote sustainability through prac-tices such as integrated land use and transportationplanning and cross-modal planning. Transportationplanning also should conduct forward-looking analysesof demographics, market preferences, and job locationtrends to be responsive to the emerging needs of futuregenerations.

Use Existing Institutional Structure but Address Cultural Issues

The existing institutional structure of transportationplanning—state departments of transportation, met-ropolitan planning organizations, and local planningagencies—is capable of integrating sustainabilityobjectives into the transportation planning process.Planning agencies nevertheless face cultural chal-lenges that must be overcome to address unsustain-able transportation impacts. Cultural issues must be

accommodated to enable the incorporation of sus-tainability-friendly solutions such as integrated landuse and transportation planning, cross-modal plan-ning, and full-cost pricing. These solutions requiretransportation planners to reach beyond their tradi-tional areas of expertise and work collaboratively withother agencies. Moreover, to enable accountability fortransportation investment decisions, transportationplanning institutions should be given budgetary andmanagement authority.

Adopt Use of Inclusive Long-Term Visioning in Planning

Adopting longer horizons and visioning techniques inthe development of transportation plans will enhancethe ability of planning processes to integrate sustainabil-ity objectives. Standard 20-year planning horizons needto be extended to at least 40 years to incorporate sus-tainability concepts. In addition, public involvementshould be expanded to enable plans that reflect a com-munity’s vision, have support from a broad constituency,and are therefore more likely to be implemented success-fully. Underrepresented groups such as children, theelderly, and those with low income should be included inpublic involvement, along with industry, educators, andpublic health officials. In conjunction with visioning andlonger planning horizons, backcasting should be encour-aged. Backcasting involves working backwards from aparticular desired future, or set of goals, to the present.A handful of planning institutions have begun imple-menting these practices, and their experiences can bevaluable to other agencies.

Evaluate the Broad Range of Effects ofTransportation Investments in the Planning Process

Transportation investments have a wide range of effectson the economy, the environment, and our culture. Abroad transportation planning perspective should beimplemented to enable planners to address more fullyunsustainable effects such as congestion, lack of equity,climate change, air pollution, ecological degradation,and resource depletion. In tackling these effects, plan-ning agencies should consider applying “triple bottomline” analysis to transportation planning. Triple bot-tom line analysis gives environmental quality and socialjustice equal weight with financial considerations.When transportation’s full range of effects is consid-ered in the planning process, innovative solutions canbe developed that enable reasonable growth whileaddressing sustainability.


Education Recommendation: EducateStakeholders in Issues of Sustainability

To build consensus and institutional capacity, educationin the dimensions of sustainability including sustainabletransportation is needed. Educational methods such asprofessional development and training; public outreach;institution building; information dissemination; andadaptation of elementary, secondary, and tertiary cur-ricula should be applied to appropriate stakeholdergroups. For example, planning professionals shouldreceive uniform and legitimized training and educationto augment planners’ capabilities to include sustainabil-ity issues. Planning professionals need to be providedwith the information, resources, and skills that canenable them to deal with the complex interrelated issuesassociated with sustainability. As another example, cur-ricula on sustainability should be used in elementary,secondary, and tertiary schools to instill the values ofsustainability in younger generations. The general pub-lic should be educated in sustainability and the impor-tance of individual decisions and behavior throughoutreach and other forms of information dissemination.

Recommended Areas for Further Research

Methods and Models for Longer Time Horizonand Broader Reach Planning

Tools that enable the integration of sustainable trans-portation practices into the planning process should bedeveloped. Tools are particularly needed in the areas ofsustainable urban development, finance, freight, green-house gas emissions, road ecology, and public decisionmaking. Research also is needed on the extent to whichmethodologies such as longer horizon planning, vision-ing, and backcasting will result in more sustainabletransportation.

Individual Transportation Behavior

Research current behavior patterns and the circumstancesunder which current behavior might change. Researchattitudes toward sustainability and environmental issues.These data will enable improved planning for the nextgeneration of travelers, shippers, and carriers.

Alternative Energy Sources and TechnologicalAdvancements

Research innovative solutions to unsustainable effects oftransportation including, but not limited to, the following:

• New vehicle and fuel technologies such as smallspecialized vehicles, plug-in hybrid vehicles, electricguideways, and fuel cell vehicles;

• Alternative vehicle concepts such as car sharingand smart paratransit;

• New low-carbon fuels such as biofuels, electricity,and hydrogen;

• More energy-efficient combustion engine vehicles;• Sustainable means of freight movement; and• Pricing and full costing of fuel and roadways.

Case Studies and Pilot Projects

Through pilot projects and case studies, research inno-vative processes, tools, and methods that demonstratethe integration of sustainability concepts into trans-portation planning. Case examples and pilot projectsshould be conducted with metropolitan planning organi-zations and state agencies to demonstrate innovationssuch as visioning; longer planning horizons; backcasting;ecological mitigation; land use and transportation inte-gration; introduction of new modes, vehicles, and fuels;and cross-modal planning. Air quality attainmentmethodology can be and, in a few instances, has beeneasily adapted to accommodate greenhouse gas esti-mates. U.S. Environmental Protection Agency–fundedefforts with state energy agencies have demonstrated themerits of pilot approaches. Metropolitan planning orga-nizations and state departments of transportation arefully capable of undertaking meaningful efforts if federalfunding could provide the necessary resources.

CONCLUSION

Achieving a sustainable transportation system—one inwhich (a) current social and economic transportationneeds are met in an environmentally conscious mannerand (b) the ability of future generations to meet their ownneeds is not compromised—is not a simple task. Cer-tainly, the path to such a transportation system will bedifficult. Transportation system planners and providerswill need to work with and respond to market conditions,demographic changes, and political challenges; it will notbe possible to envision achieving sustainability otherwise.

Despite the enormity of the challenges, transportationplanning can play a significant role in a mix of publicand private actions toward the goal of sustainability.Annually, tens of billions of dollars are invested in trans-portation facilities and services by governmental units inthe United States. These investments leverage a fargreater level of private transportation investment to sus-tain the economy. Transportation planning productsgenerate, prioritize, guide, and authorize these strategic


public investments. Thus, whether decisions made withinthe planning process reflect or ignore sustainability con-cepts has a significant bearing on the likelihood ofachieving a sustainable system.

In brief, two achievable adjustments will greatlyhelp integrate sustainability concepts into transporta-tion planning practices: (a) taking a broader view withfull concern for transportation’s impacts on publichealth, equity, and the environment; and (b) taking alonger-term view with full concern for future genera-

tions. While some emerging practices embrace thesetwo adjustments, most current practices are still rootedin more limited, traditional technical methods, evalua-tion schemes, and time horizons. A national consensusconcerning sustainability, facilitated by dialogue andtechnical assistance supported by the U. S. Departmentof Transportation, will be needed to ensure that theentire transportation planning community makes thenecessary adjustments to integrate sustainability intoplanning practice.


GENERAL AND CONCURRENT SESSIONS

1 1

Welcoming Remarks and Charge to the Conference

Jim Shrouds, Federal Highway AdministrationDavid L. Greene, Oak Ridge National Laboratory

The Conference on Integrating Sustainability intothe Transportation Planning Process began with ageneral session that included welcoming remarks

from the conference sponsor and the conference com-mittee chair.

Jim Shrouds, Director of the Office of Natural andHuman Environment, Federal Highway Administration(FHWA), offered welcoming remarks on behalf of theconference sponsor. He compared the challenges of sus-tainable transportation to those of “the perfect storm.”The three storm systems that unite to create these chal-lenges are growth in population and employment,growth in travel and congestion, and growth in concernfor the environment.

FHWA sees sustainable mobility as a systemwide issueand is undertaking various efforts in this area. In particu-lar, cost-effective and sustainable mitigation research anddevelopment, ecosystem initiatives, and FHWA’s Centerfor Global Climate Change, which researches ways toreduce greenhouse gas emissions and respond to theimpacts on transportation infrastructure from climatechanges such as a rise in sea level, were noted.

Three of the challenges that FHWA faces are (a) pro-viding better linkages between transportation planningand environmental requirements in project develop-ment, (b) engaging stakeholders early and continuouslyin the transportation planning process, and (c) improv-ing integration of transportation and land use planning

at the local level. By facilitating discussion and expand-ing the horizons of participants, the conference is help-ing to meet those challenges.

David L. Greene, conference chair, welcomed partic-ipants to the conference and provided an overview of itsstructure and objectives. He charged participants to takeownership of the conference and, through their partici-pation, to contribute to the overall success of the ses-sions and of the conference. The role of the conferencecommittee members is to advise the U.S. government onhow to incorporate sustainability into transportationplanning on the basis of the results of this conference.Dr. Greene requested that the participants provide infor-mation and advice to committee members to assist themin meeting this charge.

Examples of working definitions of sustainabilitywere provided, including the definitions supported bythe United Nations World Commission on Environmentand Development (the Brundtland Commission) and thedefinition provided in a joint statement of 63 of theworld’s scientific academies. Society cannot be sustain-able if its parts are not sustainable, and transportationnot only must be sustainable but also must contribute tothe sustainability of society.

Dr. Greene noted that the conference has broughttogether an outstanding group of participants andexcellent speakers for a program focused on obtainingparticipant input for the conference sponsors.

1 2

Keynote Address

Thomas B. Deen, Consultant

T homas B. Deen began his keynote address by dis-cussing previous efforts that have been under-taken on issues of sustainable transportation.

Many of the participants in this conference were active10 years ago, when work in this area was just begin-ning. Today, through this conference, participants aretaking the concept of sustainability one step further andasking how to operationalize it and make it effective.

There are four broad human aspirations: peace, free-dom, economic well-being, and a good physical envi-ronment. The last two of these are linked in that newindustry (or economic well-being) often leads to envi-ronmental degradation. This is the crux of sustainabledevelopment—how to have economic growth withoutenvironmental decay. In the short term, jobs and growthtend to trump environmental concerns. Examples arethe increase in the percentage of workers driving alone,the decline in carpooling, the drop in transit share, theincreased length of the peak hour, the decline in urbandensity, and ever-increasing energy imports. On the

basis of these facts, Mr. Deen cannot see how one canargue that sustainability has any traction in the realworld; even the most optimistic would say that we mustdo better.

The daunting task of this conference is to movebeyond endorsing sustainability in principle and toobtain political traction to influence transportation pol-icy and activities. Mr. Deen provided the conference par-ticipants with some optimism. While a single definitionof sustainability eludes diverse groups, it is not the firstpowerful concept that suffers from the lack of a precisedefinition. Precise definitions also elude art and religion,but progress in these areas has been made. Soon a pointwill be reached where even critics will see the limits ofthe earth’s resources and man’s effects on them, andchange will be forced.

The job of the conference participants is to figure outhow to put sustainability objectives into the real worldand make changes. It is necessary to be prepared for thetime when crisis demands ideas that can be implemented.

1 3

Presentations on Transportation Sustainability Indicators

Mark DeLuchi, University of California (presented by David L. Greene, Oak Ridge National Laboratory)

Mike MacCracken, Climate Institute Daniel Sperling, University of California, DavisDavid G. Burwell, Prague Institute for Global Urban DevelopmentElizabeth Deakin, University of California, BerkeleyRichard Forman, Harvard University

HEALTH

Mark DeLuchi

David Greene presented on behalf of Mark DeLuchi,who was unable to attend the conference. The presenta-tion, External Costs of Motor Vehicle Use: Status andTrends, discussed transportation’s external costs as wellas its impacts on human health. The external costsexamined in the presentation included accidents, con-gestion, oil use and energy security (military expendi-tures, macroeconomic costs, pecuniary costs), airpollution (human health, visibility, crops, forests), andnoise. The presentation provided estimates of these costsas well as trends in impacts and costs.

Since 1990, all of the external costs of transportationexcept those resulting from air pollution have increasedsubstantially. The cost increases have occurred becauseof a steady increase in vehicle miles traveled despite someareas of improvement such as a reduced involvement ofalcohol, increased use of seat belts, and improved vehiclesafety. The difficulty of reducing the growth of vehiclemiles traveled suggests that health, safety, noise, conges-tion, and energy security costs of motor vehicle use mayhave to be mitigated by reducing impacts per mile. Suchmitigation, however, faces many challenges, and it is notlikely that spotty management of per mile impacts willresult in a sustainable transportation system.

Transportation sustainability depends on the develop-ment of personal transportation choices that reduce theexternalities of transportation without compromisingany of the benefits of private motor vehicle use. This will

require new visions of integrated development of towns,transportation infrastructure, and transportation modes.

CLIMATE CHANGE

Mike MacCracken

Mike MacCracken began his presentation, ClimateChange and Sustainable Transportation: The Need toEnd Our Addiction to Fossil Fuels, by dividing the cli-mate change issue into the following three questions:

1. How is the climate expected to change, and are wealready seeing the early signs of these changes?

2. What are the likely environmental and societalimpacts of changes in carbon dioxide concentration andthe climate, and to what extent can adaptation amelioratethe projected negative consequences?

3. What are the options for limiting the human-caused factors inducing these changes, and how rapidlyand economically can they be implemented?

Answering these key questions is complicated by sev-eral unusual factors including long time horizons; thefact that all that can be expected given the complexity ofsociety and the environment is a projection of a range ofpossibilities; and the fact that the causes, impacts, andcontrol of the climate change issue are necessarily inter-national. Dr. MacCracken then summarized fossil fuels’benefits to society as well as the major effects they haveon the environment. He demonstrated that the rise in

carbon dioxide concentration is unusual and that aver-age temperatures are in fact higher because of humanactivity. Other climate measures are projected to changebecause of fossil fuel use: precipitation and the rate ofevaporation will increase and sea level will rise. It isimportant to be aware that changes in these measuresmay not be smooth; abrupt changes are possible.

Adaptation will be essential regardless of choicesmade concerning mitigation. Past emissions havealready initiated climate change, and implementation ofmitigation will merely determine the rate of climatechange. With regard to the impacts of climate change onparticular regions, only generalized projections are pos-sible. However, tools have been developed to indicatelevels of likelihood and confidence, and particularregions and sectors should use these tools to enhancelong-term planning.

The presentation concluded with the message thattransportation is not only responsible for emissions ofgreenhouse gases but will also be affected by the chang-ing climate. To be sustainable, the transportation systemmust address adaptation as well as mitigation.

ENERGY

Daniel Sperling

Daniel Sperling’s presentation on transportation energysustainability began by outlining the upward trends inenergy use and greenhouse gas emissions. Rapidincreases in worldwide energy use are expected to con-tinue, and carbon dioxide emissions are increasing, withan increasing proportion from transport.

Potential methods to reduce greenhouse gas emis-sions and oil use were discussed. Suggestions includedchanges in behavior such as driving less and use of effi-cient, low-carbon modes of transportation; changes intransportation and land use formats such as new modes(car sharing, smart paratransit, dynamic ridesharing),specialized vehicles, and more efficient land use pat-terns; and changes in technology and fuels such as moreenergy-efficient vehicles and use of low-carbon fuels.Large reductions in greenhouse gases are possible withelectric drive and alternative fuels. Although previousalternative fuels, such as synfuels, methanol, ethanol,and compressed natural gas, failed because of cost andlack of large societal benefits, more promising alterna-tive fuels such as cellulosic ethanol, battery electric vehi-cles, and hydrogen fuel cell vehicles have high efficiencyand reliability and zero to near-zero emissions.

Dr. Sperling recommended that signals be sent to con-sumers and industry to reduce energy consumption andgreenhouse gases. More efficient use of transport,improvements in conventional vehicles and hybrid elec-

tric vehicles in the near term, and longer-term investmentsin advanced technologies should be encouraged. Researchinto and development of clean and renewable energysources should be expanded, as should experimentationwith new vehicles and services.

EQUITY

David G. Burwell

David G. Burwell discussed the relationships betweenequity, social stability, and sustainable transportation.Traditionally, the equity and social issues of trans-portation were thought to affect only the poor. Morerecently, however, these issues have been recognized asaffecting a much broader range of the demographic,including low-income and minority groups, seniors andthe elderly, children, and the physically disabled. Theextent of the impact also is much broader and includesaccess to transportation services, lifestyle (active versussedentary as well as social isolation), and communitycohesion. Community cohesion is required to be con-sidered in all transportation plans and is defined by theextent of civic institutions, trust of political institu-tions, density of acquaintances, and degree of familyand friendship networks.

The equity and social impacts of transportation placechallenges on transportation planning. The challengeswill require better planning management that accom-modates notions of social equity across populationgroups with respect to access, quality of life, and com-munity cohesion. Current transportation services, inconjunction with present settlement patterns, generatetoo many social burdens and insufficient social benefitsacross interest groups.

People have been designed out of many urban areas,which contributes to increases in obesity, increases inType 2 diabetes in minority children, reductions in theindependent mobility of children (e.g., parents mustdrive children to school), and reductions in senior citi-zen travel. Transportation, if properly planned, couldbuild social stability by renewing neighborhoods, nur-turing a sense of community, improving safety and secu-rity, improving access, promoting public health, andshaping growth to minimize sprawl.

The following activities should be undertaken tomove toward including the impacts on equity and socialstability in transportation planning:

• Study community cohesion as a planning factor, asrequired by 23 U.S.C. 109(h)(2);

• Improve accountability of agencies and commu-nity partners in addressing transportation, equity, andsocial stability;

1 4 INTEGRATING SUSTAINABILITY INTO THE TRANSPORTATION PLANNING PROCESS

• Place intense focus on community engagement inall planning efforts to understand equity and social sta-bility impacts; and

• Strengthen transportation and land use partner-ships as a primary strategy for good equity and socialstability outcomes.

LAND AND COMMUNITY

Elizabeth Deakin

Elizabeth Deakin began her presentation on land use,development, and sustainable transportation by high-lighting key strategies for sustainable development andtransportation in urban, suburban, and rural areas. Thefollowing are among the key strategies for sustainableurban and suburban development:

• Investment and reinvestment in existing districtsand neighborhoods, including preservation, renovation,and reuse of structures;

• Upgrades to infrastructure (sewer, water, streetsand highways, telecommunications, parks);

• Upgrades to services (schools, police, fire);• Development of higher-density communities, espe-

cially near transit;• Development of mixed-use real estate, especially

in downtowns and city centers; and• Infill of urban areas to create contiguous growth.

These urban and suburban development strategiesshould be coupled with transportation strategies such assidewalk improvements, transit service improvements,signal timing favoring person trips rather than vehiclemovements, and clean and well-paved streets.

In rural areas, the key strategies for sustainabledevelopment are slightly different and include the fol-lowing:

• Preservation and renewal of main streets and vil-lage centers;

• Preservation of rural landscapes and views;• Conservation of agriculture and open spaces;• Cluster development; and• Economic development and job training to main-

tain, increase, diversify, and improve jobs.

As with urban and suburban areas, rural sustainabledevelopment strategies should be coupled with trans-portation strategies as follows:

• Traffic calming on entering towns,• Sidewalks and bike lanes in towns and walking

trails and bike paths through the countryside,

• Road location and design that take advantage ofscenic vistas and historic sites and that protect environ-mentally sensitive areas, and

• Road ecology.

The following are among the challenges facing sus-tainable transportation and development:

• It is easier to keep doing what you know than totry something new.

• Reuse, rehabilitation, renovation, and infill can becostly and may generate opposition.

• Infrastructure provision, pricing, and fundingpolicies sometimes favor new areas.

• Design standards for arterials and highwaysemphasize vehicle throughput to the detriment of otherstreet functions.

• Funding for sidewalks or street trees is lacking.• It is difficult to meet transportation needs in low-

density suburbs and rural areas for those without cars.• There is not enough funding for operations and

maintenance.

Despite these challenges, successes are found all overthe country. The successes, however, are not yet trans-lating into an overall development trend. Some regionsare building on project successes to devise a regionalstrategy, and some state departments of transportationare reforming their policies to integrate land use andcommunity values.

The differences between the success stories and the sto-ries of those who have tried and failed were summarized.Environmental quality, equity, and economic develop-ment are fundamental objectives of planning processes,not post hoc evaluation criteria. In instances of success,planners are not just forecasting but also backcasting tofigure out how to get to a future that people want.

HABITATS AND ECOSYSTEMS

Richard Forman

Richard Forman began his presentation by stating thatthe objective of sustainable transportation with regardto habitats and ecosystems should be to mesh safe andefficient mobility with natural processes and biodiver-sity. Society should aim to improve natural systemsalong the road network while reestablishing a connec-tivity of natural areas and green corridors that the roadnetwork has cut into small parcels. The presentationthen focused on seven aspects of road ecology:

1. Road kill. This is generally a minor issue excep-tion when animals that reproduce slowly are affected.

1 5PRESENTATIONS ON TRANSPORTATION SUSTAINABILITY INDICATORS

2. Traffic disturbance and wildlife. A study was dis-cussed that found that low-volume roads do not have anystatistical effect on the breeding or existence of birds sur-rounding the roadway. As volume on roads increases,however, the study showed a significant effect on thebreeding and existence of birds. The size of the affectedarea also increases as traffic volumes increase. Solutionsto the impacts of traffic on wildlife may include improvedvehicle and pavement designs that reduce noise.

3. Roadside vegetation. A primary function of road-side vegetation is safety. If roadside trees narrow thevision ahead, drivers slow down. Roads in the UnitedStates, however, are designed for speed, with grassyopen areas along the roads. Trees planted up to the sideof the road could improve safety by reducing speeds andat the same time provide habitat for wildlife.

4. Connectivity of land. The existing road networksevers the land and affects the habitats and migration

patterns of wildlife. Overpasses to increase connectivity,not only for animals but also for farmers and hikers,should be used.

5. Water and aquatic ecosystems. Sedimentation,road salt, and other pollutant runoff from roads affectwater quality. Such impacts, however, can be mitigatedby disconnecting roads from water bodies and by usingsoil as a filtering substance for runoff.

6. Road density. The current road network’s insensi-tivity to ecology was discussed, and an ecosystem-friendly transportation infrastructure that maintainslarge road-free areas and concentrates traffic on a fewlarge roads was described.

7. Regional transportation planning. Currently, airquality is the only environmental impact of transporta-tion that is adequately modeled on a regional basis. Sim-ilar modeling should be conducted for other majorenvironmental issues.


1 7

Concurrent SessionsWhat Are the Challenges?

William R. Black, Indiana UniversityJoan Ogden, University of California, DavisMichael Wang, Argonne National LaboratoryKevin E. Heanue, ConsultantBob Johnston, University of California, DavisJohn P. Poorman, Capital District Transportation Committee, AlbanyArthur (Chris) Nelson, Virginia Polytechnic Institute and State UniversitySteve Lockwood, PB ConsultTom Sanchez, Virginia Polytechnic Institute and State UniversityChristina Casgar, U.S. Department of TransportationLee Schipper, World Resources InstituteMartin Lee-Gosselin, University of Laval, Canada

This section provides a synthesis of the presenta-tions and discussions that occurred in the initialsessions of four concurrent sessions on the fol-

lowing topic areas: technology, tools and institutions,policy, and behavior. In each concurrent session, twopresentations were followed by a facilitated discussion.The purpose of the initial concurrent sessions was todiscuss the challenges facing sustainable transportationin each of the four topic areas.

CONCURRENT SESSION I-1: TECHNOLOGY

William R. Black, FacilitatorJoan Ogden and Michael Wang, Presenters

Presentations

Joan Ogden discussed the potential role for hydrogenin a sustainable transportation system. She outlinedseveral reasons why hydrogen should be considered asa transportation fuel, including its zero or near-zeroemissions at point of use, low to zero well-to-wheelsemissions of both air pollutants and greenhouse gases

with some supply pathways, ability to be made fromdiverse sources (fossil, renewable, nuclear), wide usetoday, the rapid progress in hydrogen and fuel cell tech-nologies, and potential to enable new products and ser-vices that would transform the way energy is used andproduced. In addition, hydrogen could reduce green-house gas and air pollutant emissions and utilizediverse energy supplies.

Barriers to a hydrogen economy include the need todevelop emerging technologies while adapting currenthydrogen technologies for a hydrogen energy economy(e.g., fuel cells, hydrogen storage for vehicles), the cur-rent high cost of hydrogen end use technologies, the cur-rent lack of infrastructure to deliver hydrogen toconsumers, and the lack of consistent policies reflectingthe external costs of energy. Hydrogen also presentstechnical challenges. For instance, current automotivefuel cells are many times more expensive than gasoline,the lifetime of fuel cells is currently too short, there areunresolved system issues with heat and water manage-ment, hydrogen is bulkier and heavier than liquid fuels,and no current hydrogen storage technology satisfiesautomobile company requirements with regard to cost,range, and refueling time. The technology to producehydrogen at a large scale and low cost from fossil fuels

is well established. Small-scale production of hydrogenat refueling sites, however, is under development and isfacing issues such as cost, efficiency, and system integra-tion. For hydrogen to be sustainable, pathways must bezero carbon and zero emissions.

Even under optimistic scenarios, it will be severaldecades before hydrogen can affect emissions on aglobal scale. Dr. Ogden recommended the followingactions to support hydrogen: research and developmenton hydrogen technologies, public–private partnershipsto demonstrate hydrogen technologies, the institution offederal and state governments as early adopters ofhydrogen technologies, the establishment of codes andstandards for safe operation in energy applications, andanalysis to better understand the societal costs of energyand the role of hydrogen in the future energy system.

Michael Wang discussed the life-cycle effects ofvehicle and fuel technologies. The gap between U.S. oildemand and domestic oil supply will continue to grow,new-vehicle fuel economy in the United States has notimproved measurably since 1985, and the UnitedStates will continue to have the highest total green-house gas emissions. The reduction in criteria pollu-tant emissions has been a bright spot in the UnitedStates.

The life cycle of fuel can be defined as “well to wheels”or “well to pump + pump to wheels,” and the entire lifecycle needs to be considered in energy and environmentalassessments. Oil use and greenhouse gases are major chal-lenges for a sustainable transportation system. However,efficiency improvements, combined with fuel switches,could significantly reduce oil use and greenhouse gas emis-sions of motor vehicles. As tailpipe emissions continue todecline, well-to-pump emissions of criteria pollutantscould become a significant share of total well-to-wheelemissions, and this portion of the life cycle should not beignored. Advanced vehicle and fuel systems need to becarefully examined to ensure achievement of intendedenergy and emission benefits.

Discussion

After the two presentations, William Black facilitated adiscussion. Topics included ways in which hydrogenmight interact with other infrastructure and trends, theneed to design transportation infrastructure now forfuture hydrogen compatibility, and the ability to applytransportation planning tools to the hydrogen economy.The need for technological change must be communi-cated effectively to the public. To motivate politicalaction, a global understanding of the long-term problemand the need to make decisions now to affect results 50years in the future is necessary.

CONCURRENT SESSION I-2: TOOLS AND INSTITUTIONS

Kevin Heanue, FacilitatorBob Johnston and John Poorman, Presenters

Presentations

Bob Johnston discussed the sustainable transportationplanning tools available to metropolitan planning organi-zations and state departments of transportation. Currentsustainable transportation planning is a medium-rangeprocess that ignores most impacts. A policy analysisframework that requires long-range comprehensive plan-ning should be developed and implemented.

Once such a policy framework is in place, existingtools and models can be used to facilitate the sustain-able transportation process. Within agencies possessingadequate resources, there is a technical capacity toengage in land use and transportation modeling. Dr.Johnston provided an overview of models currently inuse throughout the United States and noted the cost-effectiveness and appropriate scale of use of each model.

John Poorman offered insight into the current stateof transportation planning’s institutional frameworkand culture. Missed opportunities in the sustainabletransportation movement were discussed. The recenttransportation funding reauthorization debate was onesuch missed opportunity to promote sustainability intransportation.

The current institutional structure for transportationplanning is capable of supporting sustainable planning.However, the institutional culture of planning organiza-tions inhibits advancement toward the integration ofsustainable concepts. Transportation planning is a slowprocess that is constantly in transition. There is a lack ofinstitutional understanding about the future and a needfor metropolitan planning organizations and statedepartments of transportation to embrace uncertaintyin the planning process.

Metropolitan planning organizations and statedepartments of transportation must approach trans-portation planning as a multipurpose process and notlimit their perspective to only one mode. Finally, long-range transportation planning and community forma-tion and land use planning require improved funding.

Discussion

Kevin Heanue facilitated this session’s discussion. Thediscussion focused on the many challenges facing theimplementation of planning tools and models within the


sustainable transportation movement. The discussionidentified the following issues:

• Lack of a sustainability requirement in the plan-ning process;

• Cultural resistance to the sustainability movement;• Lack of resources for the sustainability movement;• Existence of political pressures;• Lack of accountability within the transportation

planning process;• Lack of performance measures;• Variation in forecasting methods—state, local,

and federal; • Differences in metropolitan economics and gov-

erning;• Overemphasis on model running and lack of

emphasis on data feeding; and• Difficulties in modeling equity impacts.

CONCURRENT SESSION I-3: POLICY

Arthur (Chris) Nelson, FacilitatorSteve Lockwood and Tom Sanchez, Presenters

Presentations

Steve Lockwood mentioned some of the challenges facingpolicy with regard to sustainability. They include posi-tional/political sustainability, institutional/financial sus-tainability, program sustainability via accountability (i.e.,systems development, output efficiency, and mobility andsafety outcomes), and environmental sustainability (i.e.,regulatory requirements and program externalities). Tocomplicate matters further, sustainability goals encompassseveral overlapping policy arenas including technology,demand management, and supply management. In addi-tion, issues of sustainability lie within the span of controlof all levels of government—federal, state, regional, andlocal.

Mr. Lockwood discussed the role of system opera-tions in a sustainable transportation system. He summa-rized the effect of system operations and management onroadway operating regimes for both recurring and non-recurring causes of delay. In general, potential reductionsin delay are minimal except for incident management ofbreakdowns and crashes. In that case, a reduction of 20percent is possible. With regard to the impact of opera-tions on emissions, even the most cost-effective emissionreduction strategies do little for mobility or congestion(except pricing).

Trends in system operations were discussed, includingreductions in system expansion coupled with a focus on

the efficiency of available capacity, significant improve-ments in speed–flow regimes, improvements in safetyand security, reductions in modal distinctions, and possi-bly the integration of operations into the planningprocess. Transportation providers are moving from pro-viding a network and developing projects to improvingmobility through system operations and management.

Tom Sanchez discussed the equity considerations andconcerns of sustainable transportation. From a researchperspective, it is important to identify the constraintsthat prevent people from participating adequately in allaspects of society, including education, employment,housing, and public services. There are several areas ofconcern in transportation equity research: demographictrends, personal transportation costs, indirect economicand social effects, health effects, language barriers, citi-zen participation, and employment and business oppor-tunities within the transportation industry.

Discussion

After the two presentations, Arthur Nelson summarizedthe statistics of anticipated development over the next30 years and the implications that this development mayhave for highways. Among the implications areincreased vehicles, vehicle miles traveled, and lane miles.He posed the following policy questions:

• Where should this development be built?• How should this development be configured?• How should transportation systems be designed to

serve this future development?• What policies and policy processes are needed to

achieve this at the federal level?

Among the policy challenges facing sustainable trans-portation are the lack of broad consensus on nationaltargets for sustainability; the absence of nationally gal-vanizing goals for sustainability; and the lack of broadpublic understanding of the issues, challenges, choices,and implications of choices with regard to sustainability.

CONCURRENT SESSION I-4: BEHAVIOR

Christina Casgar, FacilitatorLee Schipper and Martin Lee-Gosselin, Presenters

Presentations

Lee Schipper addressed the role that behavior plays inachieving sustainable transport. He focused on the role

1 9CONCURRENT SESSIONS: WHAT ARE THE CHALLENGES?

that the United States plays in shaping the worldwideview of sustainable transport and the steps being takentoward implementing sustainable transport in theUnited States.

Unpredictable changes in behavior hamper the sus-tainability process. Intervention could enable the sus-tainable transportation movement at three levels ofbehavior: the macro level (politicians), the meso level(administrators and transport professionals), and themicro level (individual travelers).

Key areas where further research is needed linkingtransportation and behavior were identified. There is aneed for a shift from typical destination studies to ananalysis of the transportation decision-making process.To achieve sustainable transport in the United States,Americans need to develop cultural recognition and costinternalization of the basic ingredients of sustainability.

Martin Lee-Gosselin discussed the reasons behavioris seen as a problem in sustainable transportation plan-ning and policy. He also spoke to ways researchers areresponding to the complexity of evolving transportationbehavior.

Dr. Lee-Gosselin first defined the externalities andunanticipated consequences (good and bad) that resultfrom the choices of travelers. He then described the sixinconveniences of behavior, including the differencebetween preference and choice and the complexities that

arise from the fact that mode and route choices dependon more than just a traveler’s work commute.

Several short- and long-term actions being taken byresearchers to address the complexity of behavior wereidentified. It is helpful to understand which decisionsare important to whom (individuals, firms, public agen-cies). There is a need to understand both conventionaldata sources and how travelers interpret and use infor-mation on travel options.

Dr. Lee-Gosselin proposed that the transportationindustry design behavior indicators and establish a bal-ance between persuasion, pricing, and regulation. Behav-ior change in favor of sustainable transportation willrequire feedback at the local, regional, and national levels.

Discussion

Christina Casgar facilitated the discussion during this ses-sion. The discussion focused on the limitations of humancognitive ability and how these limitations affect the plan-ning process. The inability of the individual to grasp theidea of sustainability was attributed to the restriction ofthought to short-term versus long-term thinking. The par-ticipants also made an attempt to determine the extent towhich changes in behavior had to occur before changes intransportation could be achieved.


2 1

Reports on the Concurrent SessionsWhat Are the Challenges?

Genevieve Giuliano, University of Southern CaliforniaThomas M. Downs, Eno Transportation FoundationAnne Canby, Surface Transportation Policy ProjectRichard Gilbert, Centre for Sustainable Transportation

Conference participants assembled in a general ses-sion to discuss key points and areas of generalagreement identified in the initial concurrent ses-

sions on the challenges facing sustainability in each ofthe four topic areas: technology, tools and institutions,policy, and behavior. A rapporteur provided an overviewof each initial concurrent session.

CONCURRENT SESSION I-1: TECHNOLOGY

Genevieve Giuliano, Rapporteur

Participants primarily discussed the technology offuture energy sources with regard to production, distri-bution, and storage. A 30- to 70-year time frame isrequired for the implementation of new transportationtechnologies. To make informed policy decisions aboutfuture energy sources and their sustainability, a full“well-to-wheel” evaluation is required.

In the short term, future energy sources are likely toinclude hybrids, natural gas, ethanol, and unconven-tional oil. In the long term, hydrogen appears to be themost promising energy source, but other options such asnuclear, electric, and sequestration also need to be con-sidered. Hydrogen has the most potential, on the basisof its diverse sources of production, near-zero emissions,and rapid technological advances. The technologicalchallenges associated with hydrogen include its highcost, limited fuel cell lifetime, heat and water manage-ment, on-vehicle storage, production systems, and riskand uncertainty of some production sources. The transi-

tion to hydrogen also presents such obstacles as con-sumer acceptance and development of compatible pro-duction, storage, and distribution systems. Whether toproduce hydrogen from fossil fuels as an interim phaseto production via electricity is another question.

In addition to the development of future energysources and the reduction of greenhouse gases, areaswhere technology could be successful in meeting sus-tainable transportation challenges include adaptation toclimate change, improved safety, noise reductionthrough sound-absorbing pavements and quiet cars,congestion relief through improved system manage-ment, and facilitation of mobility. The participants con-cluded that technology research should be focusedwhere solutions are the most promising with regard totheir positive impact on sustainability.

CONCURRENT SESSION I-2: TOOLS AND INSTITUTIONS

Thomas M. Downs, Rapporteur

Participants discussed numerous challenges to integrat-ing concepts of sustainability into the tools and institu-tions of the planning process. To start, sustainability isnot a requirement in the planning process, and politicalpressures and a lack of resources inhibit the movementtoward sustainability.

Additional challenges are a lack of accountability inplanning organizations; the absence of performancemeasures; the variety of forecasting methods across fed-

eral, regional, state, and local levels; a culture of beingin the lead rather than a culture of collaboration; dif-ferences in metropolitan economics and governing;overemphasis on model running and lack of emphasison data feeding; absence of a 50-year planning require-ment; inability to assess equity or public involvement;lack of cross-disciplinary training; and the need toestablish sustainability as an important issue at thenational level.

CONCURRENT SESSION I-3: POLICY

Anne Canby, Rapporteur

The participants in this session discussed how to setpriorities, fund programs, and establish rules toimplement policy that furthers the goal of sustainabletransportation. The lack of a uniform definition ofsustainability combined with the complexity anduncertainty of the issues limits the ability to addressthese issues. The importance of credibility in engagingothers and garnering broad support for the issues ofsustainability was also discussed. Surrogate issues canbe used to reach desired outcomes with regard tosome aspects of sustainability such as climate change.The building of coalitions around these issues willdevelop support for sustainability that can be drawnon when the time is right for policy development. Itshould be possible to build support for change in thefollowing areas:

1. Energy availability at a reasonable price,2. Safety,3. Health (asthma, obesity),4. Environment (ecosystems, biodiversity, air and

water pollution), and5. Equity.

The participants discussed congestion and mobilityin addition to the fives areas listed above but questionedwhether these issues fit within the framework of sus-tainability.

Flexibility in the transportation system and its institu-tions is important, since it is not known what will triggerthe need to address sustainability. Currently, the trans-portation system and its providers are not prepared toaddress sustainability. Institutional and financial rigiditiesprevent steps toward sustainability from being taken. Thesession participants discussed the need for better ways tomeasure project and agency performance, fiscal flexibilityto enable addressing changing circumstances, and coali-tions to build the conditions to address solutions.

CONCURRENT SESSION I-4: BEHAVIOR

Richard Gilbert, Rapporteur

Participants discussed approaches to behavior (i.e.,what people do), whether they are travelers, shippers,decision makers, or others. Two general approacheswere described. One is the Confucian approach, alsoembraced by American behaviorists, which looks forthe causes of behavior in the environment or context inwhich it occurs. The other is the Aristotelian approach,which holds that behavior is the result of people’schoices, the product of will or mind. Confucians wouldchange behavior, if they were so inclined, by changingits circumstances or consequences. Aristotelians seek tochange behavior by persuasion, perhaps backed up bychanges in its context. The limited evidence concerningwhat it takes to change transport activity suggests thatConfucians may have better answers. Desirable out-comes are more likely to be achieved by judicious useof incentives and disincentives and by otherwise struc-turing environments to favor what is required than byconvincing people that change is necessary.

Five challenges were identified:

1. Giving appropriate feedback. Transport indicatorsare not good enough to support provision of effectiveconsequences of good or bad transport activity.

2. Achieving effective balances of regulation, pricing,and persuasion. Each has its role.

3. Recognizing that transport behavior is among themost complex things that people do.

4. Recognizing the importance of the meso level (i.e.,administrative and expert behavior) versus the macrolevel (politicians) and the micro level (travelers and ship-pers).

5. Coping with longer time scales (i.e., beyond thenext fiscal year).

Participants identified 12 research areas related tobehavior and sustainability:

1. Determining the extent to which it is necessary tochange hearts as well as heads;

2. Empowering stakeholders;3. Establishing the importance of alternatives;4. Understanding individual transport behavior bet-

ter;5. Understanding freight trends and who is responsi-

ble for them;6. How to get at kids in school, from kindergarten to

Grade 12;7. Operationalizing meso planning;


8. Developing indicators of necessary versus discre-tionary change;

9. Making use of fairness in transport planning;10. Making better use of natural experiments;

11. Determining a “reasonable level of mobility”;and

12. Integrating environmental management andtransport management at regional levels.

2 3REPORTS ON THE CONCURRENT SESSIONS: WHAT ARE THE CHALLENGES?

2 4

Panel DiscussionPotential Solutions to Challenges

Kevin E. Heanue, Consultant (Moderator)Anne Canby, Surface Transportation Policy ProjectJohn Horsley, American Association of State Highway and Transportation OfficialsHal Kassoff, Parsons BrinckerhoffJohn Pucher, Rutgers UniversityG. Alexander Taft, Association of Metropolitan Planning Organizations (retired)

On the second day of the conference, a round-table discussion was held by a distinguishedpanel. The participants discussed potential solu-

tions to the sustainability challenge.Anne Canby indicated that her view of sustainability

includes the minimization of environmental degrada-tion, the minimization of energy consumption, thestrengthening of communities and their residents to self-sufficiency, and the reduction of public and personalhealth risks from transportation. Sustainability requiresexamining transportation in a broader context that getsbeyond a project perspective.

Approaches for redirecting transportation investmenttoward sustainable objectives were outlined. Approachesdealing specifically with the planning process includedthe creation of valid planning processes in state highwayagencies; the expansion of the long-range planningprocess to include collaboration and integration withenergy, environment, public health, and communitydevelopment policies; and the integration of operationsand services/modes in the planning process. Collabora-tion with public stakeholders should be expanded duringplanning before projects have been identified, and mea-sures of sustainability should be incorporated into theNational Environmental Policy Act process.

Two of the approaches deal specifically with funding.Ms. Canby recommended a change in the factors usedto distribute federal funding and in the way public-sec-tor transportation investment is funded. The decision-making authority over how to allocate funds amongstate highway agencies, regional transit operators, andregional planning entities should be shared.

Among other approaches are broadening the trans-portation perspective to encompass desired outcomes innontransportation areas as well as transportation, explic-itly including strategies to reduce accident rates and fatal-ities and reward those who reduce accidents, andchanging the way priorities are set to incorporate urbanrevitalization and minimization of land consumption.

John Horsley summarized the situation facing statedepartments of transportation (DOTs). State DOTs donot have the resources to meet requested mobility needs.They are unable to buy right-of-way because it isalready developed, they cannot build the network ofhighways that the current development pattern expectsof them, and they cannot generate the resources tomaintain the existing network.

Advocacy for sustainable transportation must comefrom the grass roots. Participation in conferences likethis should be broadened to include the land use com-munity, citizen activists, the developer community, andcity and county officials with land development respon-sibility. Given the current market, where developers arereporting greater sales per foot from urban developmentthan from big box retail shopping centers, the engineer-ing solution to transportation cannot be the onlyanswer.

The U.S. Department of Transportation should col-laborate with other federal agencies, including theDepartment of Housing and Urban Development, theDepartment of Energy, the Department of Commerce,and the Environmental Protection Agency. These fed-eral institutions need to break down silos to address thecrosscutting issue of sustainability.

Hal Kassoff began by discussing whether the conceptof sustainable highways is an oxymoron or an opportu-nity. Highways are typically viewed as part of the prob-lem and labeled antisustainable, whereas transit, freightrailroads, bicycling, and walking are parts of the solu-tion. Vehicles, however, can be made more sustainablethrough alternatives to fossil fuels, and similarly, thereare opportunities to make the highway infrastructurepart of the solution.

Most state DOTs embrace environmental steward-ship and agree that while meeting functional require-ments is the primary objective, it is not the onlyobjective. Meeting the functional requirements whilebeing environmental stewards results in sustainablehighways. In addition, most highway projects areimprovements to existing roads. Since the existing roadswere not built in accordance with today’s demandingenvironmental standards, such projects present oppor-tunities to meet the current stringent environmental andequity requirements. There are significant opportunitiesfor highway infrastructure to help meet sustainabilityobjectives in the areas of noise, water quality, ecology,equity, recycling, safety, and mobility.

A possible definition for sustainable highways is“highways that, from conception to completion,through maintenance and operations, satisfy life-cyclefunctional requirements while improving the natural,built, and social environment.” Highways will remainan enduring component of our transportation systemwith a recurring need for rehabilitation, reconstruction,and, at times, expansion. Rehabilitation, reconstruc-tion, and expansion projects present opportunities forimproving not just the functionality of highways buttheir ability to contribute to sustainability goals.

John Pucher began by questioning what is meant bymobility. It is important to distinguish between mobilityand access. There is a trade-off between mobility andsustainability, whereas it is possible to provide sustain-

able accessibility. With regard to mobility, the trans-portation system of the United States is reaching a pointof diminishing returns. The focus should be on provid-ing better accessibility as opposed to more mobility.Current lifestyle and land use patterns are addicted tomobility, but Dr. Pucher questions how much mobilitywill be enough.

Dr. Pucher also discussed the apparent dismissal ofwalking and biking as modes of transport. These modes,which are often ignored by planners and engineers, areperfect from a sustainability perspective and need to betaken more seriously. A broader view should be taken ofhealth problems related to transportation. Personalhealth is a major component of the sustainability solu-tion, and individuals should be encouraged to walk andbike for purposes of their health. Walking and bikingalso increase social interaction and independence. Trueintermodalism is required for sustainability. Intermodal-ism would coordinate all modes and integrate walkingand cycling with other modes enabling longer trips.

Alex Taft provided his perspective on metropolitanplanning and sustainability. The two keys to movingtoward sustainable transportation are a planning processinfused with public participation and the development ofan overarching vision for the community. Comment peri-ods should be extended, all neighborhoods and busi-nesses should be involved, and consensus should bereached on a plan that has strategies and projects consis-tent with its theme and objectives. All projects, includingnonmotorized and transit projects, should be prioritizedin conformance with the plan’s theme and objectives.

To avoid simply continuing what has been done in thepast, public participation must be improved. It is impor-tant to demonstrate how public participation changed theplan. In addition, metropolitan planning organizationsmust work with the community to develop an overarch-ing vision for the area that integrates concepts of landuse, environmental protection, and energy conservation.

2 5PANEL DISCUSSION: POTENTIAL SOLUTIONS TO CHALLENGES

2 6

Reports on Concurrent Roundtable DiscussionsPotential Solutions to Challenges

Genevieve Giuliano, University of Southern CaliforniaThomas M. Downs, Eno Transportation FoundationAnne Canby, Surface Transportation Policy ProjectRichard Gilbert, Centre for Sustainable Transportation

Conference participants assembled in a general ses-sion to discuss key points, areas of general agree-ment, and areas for further research identified in

the concurrent sessions on the potential solutions to thechallenges in each of the four topic areas: technology, toolsand institutions, policy, and behavior. These concurrentsessions were conducted in roundtable format. A rappor-teur provided an overview of each concurrent session.

CONCURRENT SESSION II-1: TECHNOLOGY

Genevieve Giuliano, Rapporteur

Participants discussed whether there was a role for tech-nology in each of the dimensions of sustainability. Foreach dimension in which technology could have a role, theparticipants discussed how strong that role could be, whatpolicies are needed to implement the role, and at whatlevel of government the responsibility for that technologywould reside. Technology was determined to have a majorrole in the areas of future fuels, greenhouse gases, air pol-lution, safety, and noise. Technology was seen to have amedium role in the areas of mobility and congestion and asmall role in biological impacts and equity.

The session participants concluded with three majorpoints. First, aggressive research and developmentacross an array of technologies are needed to meet thesustainability goal. Second, there is a need for researchand development and policy analysis to prepare forfuture fuel transition. Finally, adaptation to climatechange and its impacts on the transportation system

should be incorporated into the transportation planningprocess as soon as possible.

CONCURRENT SESSION II-2: TOOLS AND INSTITUTIONS

Thomas M. Downs, Rapporteur

The discussion focused on finding solutions to several ofthe challenges raised in Concurrent Session I-2. Thegroup discussed the need for a national initiative thatrecognizes and legitimizes sustainability in planning. Theslow pace of change within the federal government andits impacts on achieving sustainable transportation werealso discussed. The difficulty faced in the recent trans-portation funding reauthorization is a prime example ofthis slow pace of change.

Primary challenges brought to light as a result of Con-current Session I-2 include cultural resistance within institu-tional planning agencies and the lack of a national initiativelegitimizing the sustainability movement. Participants dis-cussed how the existing institutional structure is capable offacilitating sustainable transportation planning within local,regional, and state planning agencies. It is believed that thesystems of decision making and allocation are in place toallow for change within the planning process and that gov-ernments have the flexibility and the jurisdiction to inte-grate sustainability into the current framework. A lack ofunderstanding about what practices work and do not work,however, has created a cultural resistance to the inclusion ofsustainability considerations in the planning process.

The participants recommended that a best practiceshandbook be compiled and issued to transportation pro-fessionals. It also was suggested that a sustainabilitytraining program be established for transportation plan-ners. The participants expressed a need to establish sus-tainability at the national level. The group recommendedthat sustainability issues be tackled via pilot projects andreal-world experiments. The development of sustainabil-ity standards and a quantification of both the benefitsand the negative aspects of sustainability were encour-aged. The implementation of these practices would besteps toward legitimizing the sustainability movement.

CONCURRENT SESSION II-3: POLICY

Anne Canby, Rapporteur

The participants discussed the changing housing marketand how the current trends for urban higher-density livingwill shape the future of transportation. They also notedthat federal, state, and regional levels of government allmust play significant roles in policy initiatives.

To address sustainability concerns, the participantsencouraged policy development in the following areas:

• Broaden curricula to cover demands that will beplaced on future planners and transportation profes-sionals, including the addition of human sciences to theengineering curriculum.

• Perform research into how mode choice, vehicleuse, and energy consumption change with respect todensity, location, and land use configuration givenchanging demographic trends, residential preferences,and office–retail dynamics.

• Facilitate market forces favoring transportationsustainability.

• Establish an interdepartmental working group onsustainability (including the Department of Housingand Urban Development, the Department of Energy, theEnvironmental Protection Agency, the Department ofTreasury, and the Department of Health and HumanServices, among others).

• Create a national dialogue and build consensus onthe need for sustainability.

• Identify the barriers within institutions and poli-cies to achievement of a sustainability program.

CONCURRENT SESSION II-4: BEHAVIOR

Richard Gilbert, Rapporteur

The complexity and the limitations of human cognitiveability, which may underscore inability to engage in long-

term decision making, were discussed. Several issuesdeemed to be important to the sustainability movementwere thought to have been overlooked in the planningprocess. Two examples of unaddressed issues are (a) con-sideration of the time scale needed for longer-range plan-ning and (b) insufficient provision of information topeople affected by the planning process. Achieving bal-ance between regulation and pricing also was seen as crit-ical to attaining sustainable transportation. Finally, theparticipants emphasized the importance of identifying theappropriate level or group within the transportation plan-ning process to lead the movement toward sustainability.

Several educational and technical initiatives wereidentified as solutions to some of the challenges. Empha-sis was placed on the use of training and education tochange human behavior. Children and transportationprofessionals were cited as target groups for educationalinitiatives. The possibilities for expanding the planningprocess to create a more inclusive atmosphere were alsodiscussed. The planning process must engage hithertounrepresented and underrepresented groups, includingindustry. Improved dialogue between government andindustry must be encouraged.

In previous sessions, expansion of the transportationplanning process had been cited as critical to the successfulintegration of sustainability. It was agreed that expansioncould involve several components, including visioning. Thedesignation of funds for the visioning process at the metro-politan and state levels is necessary for its implementation.Finally, it was recommended that transportation profes-sionals include operations and capital investment issues inthe transportation planning process.

The group emphasized the need to build a conscious-ness of sustainability and discussed a strategy for achievingthis goal. A hierarchy of implementation was formulatedas a guide toward attaining sustainability. It was suggestedthat modules of sustainable education be introduced at alllevels of education, beginning with elementary school. Par-ticipants recommended that assessments of staffing andeducational needs be conducted at the state and metropol-itan levels. Implementation of a cost assessment strategyaimed at fully costing sustainable and nonsustainabletransport was also recommended. The level appropriatefor intervention—that is, the group through which to pushchange—was determined to be the meso level: experts andbureaucrats. The meso level could assist in making behav-ior changes in the macro level of politicians and at themicro level of individual travelers. The retraining of themeso group could help promote sustainable behavioramong the users and regulators of transportation.

In summary, the breakout group identified 10 solu-tion areas:

1. Focus on educating children for sustainability,both as transport’s “canaries” and as adults-to-be.

2 7REPORTS ON CONCURRENT ROUNDTABLE DISCUSSIONS

2. Focus on the training of engineers and othertransport professionals in sustainability.

3. Have empty seats in the planning process (say, anolder person, a Bangalore resident, and a fish).

4. Require a visioning element as part of the metro-politan planning organization process; designate a setshare of funds, say 7 percent.

5. Prepare a casebook of good and bad practices,mainly for educational purposes.

6. Prepare a casebook of good and bad situations(for example, which contexts sustain transit use andwhich do not).

7. Require transport planning processes to considerfull-cost pricing.

8. Provide federal resources for more, different, andbetter staffing of metropolitan planning organizations.

9. Involve industry in planning for transport sus-tainability (e.g., hold a conference for chief executiveofficers).

10. Expand the metropolitan planning organizationprocess to deal with operations issues as well as capitalinvestment.


2 9

Luncheon Speakers

Lewis Dale, General MotorsEmil Frankel, U.S. Department of Transportation

Lewis Dale offered luncheon remarks to partici-pants on the first day of the conference, and EmilFrankel offered remarks on the second day. A

summary of each speaker’s remarks follows.Lewis Dale discussed the final report of the World

Business Council for Sustainable Development’s Sus-tainable Mobility Project. Mobility 2030: Meeting theChallenges to Sustainability reflects the collective effortsof more than 200 experts from a broad set of 12 indus-trial companies. The project was initiated because of thegrowth in population and in motorization, especially indeveloping countries.

Mr. Dale identified several achievements of the reportbut noted that consensus was not achieved on everypoint. The members did agree that action is required onsustainable mobility challenges. The report presents adefinition of sustainability agreed on by the participantsand an assessment that concludes that current trends arenot sustainable. The report also serves as a wake-up callfor industry and identifies focus points for governmentand industry in moving toward sustainability.

The report, which focuses on roads and motorizedvehicle transport, adopted 12 indicators: access tomobility, user costs, travel time, reliability and comfort,safety, security, greenhouse gas emissions, impacts onthe environment and public well-being, resource use,impacts on public revenues and expenditures, equityimplications, and rate of return to private businesses. Ifpresent trends continue, some indicators, such as con-ventional emissions, safety, and affordability of goodsmobility, look better. However, others, such as green-house gas emissions, congestion, and equity, look worse.

The report outlines seven goals to reverse the indica-tors that are looking worse:

• Reduce transport-related emissions to levels wherethey cannot be considered a serious public health con-cern anywhere in the world.

• Limit transport-related greenhouse gas emissionsto sustainable levels.

• Significantly reduce the worldwide number ofdeaths and serious injuries from road crashes.

• Reduce transport-related noise.• Mitigate transport-related congestion.• Narrow the mobility “divides” that exist today

between the average citizen of the world’s poorest coun-tries and the average citizen of the wealthier countriesand between disadvantaged groups and the average cit-izen within most countries.

• Preserve and enhance mobility opportunities avail-able to the general population.

Actions that companies can take are still under dis-cussion, but to start they should continue with theextensive activities that are planned or under way, serveas catalysts to advance the understanding of sustainabletransportation within companies, continue the debateinternally, and encourage other industries to undertakesimilar studies.

Emil Frankel began with a brief update on the statusof the federal transportation funding reauthorization.He noted that the issue of sustainability is not new tothe Transportation Research Board and cited precursorsto this conference. Continued efforts with regard to sus-

tainability are necessary because it is difficult to get ademocratic society to act unless there is an impendingcrisis, and in the case of sustainability, once there is acrisis it will be too late.

The U.S. Department of Transportation struggles toprovide safe, efficient, and effective mobility while deal-ing with the intertwined issues of sprawl and urbangrowth patterns. The current pattern of developmentwas enabled by the automobile, technology, and per-sonal choice. While the sustainability of this develop-ment pattern is often questioned, it is difficult to alter. Ina democratic society it is nearly impossible to tell peoplethat low-density suburban development and depen-dence on the automobile must change.

As policies are made, trade-offs and the impacts onall aspects of sustainability must be measured. The roleof the U.S. Department of Transportation is to establisha framework for decision making including financing,planning requirements and processes, and market andregulatory processes to achieve public policy goals. Mr.Frankel emphasized the importance of discussions andbroader debate and dialogue on how to invest in trans-portation infrastructure. Capacity expansion is neededin all modes to handle goods coming into ports as wellas for mobility of people and freight.

Automobiles and trucks are the predominant modes oftransportation and are here to stay. It is important to

reduce their impacts on communities. The need to reducethese impacts places a burden on the transportation plan-ning process. Metropolitan planning organizations are keyplayers in the planning process: they balance trade-offs,make decisions, and prioritize investments. However, theylack geographic reach and resources. Significant achieve-ments have been made in transportation planning withregard to integrating the National Environmental PolicyAct and air quality conformity, but more improvements areneeded. Environmental stewardship must be incorporatedinto all aspects of transportation planning. Planning mustfocus more on systems operations management, strive forintermodality, and link to land use decisions.

Mr. Frankel emphasized the importance of technol-ogy to sustainable mobility. More efficient automobiles,new propulsion systems, greater use of hybrids, andother technological advances are moving toward sus-tainability objectives. The U.S. Department of Trans-portation, the Department of Energy, and theEnvironmental Protection Agency all have roles to playin driving technological change.

The U.S. Department of Transportation is committedto and recognizes the significance of sustainable mobil-ity and sees transportation planning as an importanttool in addressing it. Transportation planning in combi-nation with the use of priorities and indicators can assistin moving toward sustainability.


3 1

Poster Session

On the first day of the conference, seven participantspresented posters on a range of topics relevant tointegrating sustainability into the transportation

planning process:

• Transportation and Land Use Planning, Nat Bot-tigheimer, Maryland Department of Transportation.

• States, Freight, and Technical Tools: Review ofProgress and New Projects at the Center for Clean AirPolicy, Greg Dierkers, Center for Clean Air Policy.

• Sustainable Transportation Planning in the Port-land Region, Jennifer Dill, Portland State University.

• Travel Matters: Mitigating Climate Change withSustainable Surface Transportation, Sharon Feigon,Center for Neighborhood Technology.

• Sustainable Transportation Study in China, YulinJiang, China Academy of Transport Science, Ministry ofCommunication.

• What Makes a Transportation Plan Sustainable?David Kriger, iTRANS Consulting, Inc.

• Education and Sustainable Transportation, JosephSzyliowicz, University of Denver.

3 2

Conference Closing

David L. Greene, Oak Ridge National Laboratory

The conference chair, David Greene, began hisclosing remarks by summarizing the concept ofsustainability as “meeting the needs of the cur-

rent generation without compromising the needs offuture generations.” While this may seem like a basicconcept, achieving sustainability is not a simple task.That the participants of the conference have struggledwith identifying solutions to sustainability challenges isnot surprising, given the uncertainty and multipledimensions of the objective.

Despite the uncertainties, sustainability is compellingand is seen by broad groups as important and right. It isno longer only environmentalists who fight for the cause,

as demonstrated by the remarks of representatives fromthe automotive industry, the Federal Highway Adminis-tration, and state departments of transportation at thisconference. Many recognize that the sustainability crisis isright now and that there is an urgent need to make futuregenerations part of the transportation decision-makingprocess.

Dr. Greene thanked the conference participants fortheir hard work and for bringing forth their ideas andinsights. The conference, through its report, has anopportunity to define the vision of a sustainable trans-portation system clearly and to identify next steps tointegrate sustainability into transportation planning.

RESOURCE PAPERS

3 5

RESOURCE PAPER

Sustainable TransportDefinitions and Responses

William R. Black, Indiana University

This paper was prepared in response to the twoquestions noted in the conference program: Whatare the ranges of definitions of sustainable trans-

portation in practice today? How do these definitionsaffect how transportation sustainability is addressed?The first requires an inventory approach to what is outthere and what has been in fashion in the way of defi-nitions over the past 10 to 15 years. Those looking forconsensus will probably not find it here. The secondquestion is a little more difficult, if not impossible, toanswer in a precise way. There are two reasons. First,we can’t really say how something is being addressed ifwe have no general agreement on what it is. Second, themajor purpose of this conference is to try to get sustain-ability types of notions into the transport planningprocess, and this suggests that at least up to now it hasnot been addressed. Therefore, before we examine thesecond question we will at least suggest some of thecomponents of a sustainable transport system on thebasis of the definitions and other literature. Given thisbackground, we can then suggest some actions that havebeen taken toward making the transport system sustain-able with regard to these components.

SUSTAINABLE TRANSPORT: MEANINGS AND RESPONSES

It is reasonable to begin the discussion with some com-mon types of definitions of sustainability and sustain-able transport that one might find in a dictionary. Thiswill only yield words such as durable or capable of being

maintained and in reality get us nowhere. More thanthat, it angers some researchers who see these words ashaving far deeper meanings than I would intend. As aresult, moving directly to the definitions may be themost prudent course to take.

One of the first uses of the phrase “sustainability” insomething approaching the current context was in theso-called Brundtland report of 1987 (United NationsWorld Commission on Environment and Development1987). That report discussed what was referred to assustainable development, which was defined as develop-ment that meets the needs of the present without com-promising the ability of future generations to meet theirown needs. This definition can be extended withoutmajor changes to sustainable transport, which may bedefined as transport “that meets the current transportand mobility needs without compromising the ability offuture generations to meet these needs” (Black 1996).This is easy to understand on the surface, but soon wewould have to face the fact that the needs are not wellspecified, and if we could resolve that, we must thenstop and imagine how many future generations we aretalking about.

Another way of expressing these ideas would be tostate that sustainable transport represents transport andmobility with nondeclining capital, where capital wouldinclude human, monetary, and natural capital (Pearce etal. 1989; Daly 1992). Followed to its logical end, thiswould imply that natural resources could not be used inthe system (sometimes referred to as strong sustainabil-ity) unless they were used to develop additional naturalcapital (sometimes referred to as weak sustainability).

Daly (1992) does not define sustainable transport butspecifies parameters for any sector being sustainable.Within this context transport is sustainable if it satisfiesthree conditions: (a) the rate at which it uses renewableresources does not exceed their rates of regeneration, (b)the rate at which it uses nonrenewable resources doesnot exceed the rate at which sustainable renewable sub-stitutes can be developed, and (c) its rate of pollutionemissions does not exceed the assimilative capacity ofthe environment.

If we apply Daly’s conditions to the transport systemsof the 1700s and 1800s, which are often viewed as sus-tainable, we would find that these systems were on theverge of becoming nonsustainable. The major long-dis-tance transport mode of the 1700s was sailing ships.Although they used renewable wind energy, they werebecoming nonsustainable because they were depletinglumber stocks used in their construction and repair(Albion 1965). The typical transport mode of urbanareas in the 1800s was the horse–wagon–buggy–carriagesystem. That system resulted in tens of thousands ofhorses polluting streams, wells, and streets of these urbanareas and obviously exceeded the assimilative capacityof these environments (Lay 1992).

It should be apparent that today’s transport systemsfail to measure up to Daly’s second and third criteria:today’s systems are consuming fossil fuels (specificallypetroleum-based gasoline) at rates in excess of the rateat which an alternative can be produced.

Schipper (1996) states that sustainable transport istransportation where the beneficiaries pay their fullsocial costs, including those that would be paid byfuture generations. He further notes that changes intravel are associated with a number of prominent exter-nalities, including accidents, air pollution, congestion,noise, damage to species habitat, increases in carbondioxide production, and the importation of oil. It isthese externalities, and not transportation or travel perse, that threaten the sustainability of the system, accord-ing to Schipper.

Gordon (1995) is less willing to be drawn into adebate over definitions of sustainable transport andstates instead that underlying these ideas of sustainabletransport are three different visions. The first centers onchanging people and the way they live, the second onchanging technology, and the third on changing prices(Gordon 1995). In effect, she is proposing, in ratherbroad terms, what actions are necessary to make thetransport system sustainable.

Probably in an attempt to be more comprehensive,the Centre for Sustainable Transportation (1998) inCanada states that a sustainable transportation system isone that (a) allows the basic access needs of individualsand societies to be met safely and in a manner consistentwith human and ecosystem health, and with equity

within and between generations; (b) is affordable, oper-ates efficiently, offers choice of transport mode, and sup-ports a vibrant economy; and (c) limits emissions andwaste within the planet’s ability to absorb them, mini-mizes consumption of nonrenewable resources, reusesand recycles its components, and minimizes the use ofland and the production of noise.

Europeans tend to refer to this notion of sustainabletransport as sustainable mobility. Some U.S. groups alsoprefer the use of this term. The Mobility 2001 reportdefines sustainable mobility as “the ability to meet theneeds of society to move freely, gain access, communi-cate, trade and establish relationships without sacrific-ing other essential human or ecological values today orin the future” (Massachusetts Institute of Technologyand Charles River Associates 2001).

Transport Canada skirted the definition of a sustain-able transport system and sought instead to define “amore sustainable transportation system” as “one whichprovides affordable access to freight and passenger ser-vice and does so in an environmentally sound and equi-table manner” (Bell et al. 1997).

In later reports Transport Canada has set out to pro-vide a framework that addresses the social, economic,and environmental elements of a sustainable transporta-tion system. More specifically, it seeks the highest practi-cal standards of safety and security, economic efficiency,and respect for the environment so that transport’s“impact on the environment and on the health of Cana-dians is acceptable to current and future generations”(Transport Canada 2003).

Greene and Wegener (1997) and Pearce and Warford(1993) define sustainability in economic terms. In this con-text sustainability is holding the sum of the capital stocksof manufactured, human, and environmental assets at leastconstant to ensure that future generations have the samecapability to develop as current generations. Greene (per-sonal communication, June 24, 2004) has further statedthat “sustainability is a constraint on the economic systemwhich insists that we do not decrease opportunities forwell-being available to future generations below the levelwe have today. This is an ethical doctrine, and thereforeinherently subjective not objective. It defines a new marketfailure, because future generations cannot participate in theexisting marketplace to express their preferences.”

Favoring an objective conceptualization of sustain-ability, Black (2002) has asked the question, exactlywhat is it that makes the current transport system notsustainable? He has concluded that the lack of sustain-ability is due to global atmospheric problems, excessiveuse of nonrenewable resources by the transport system,excessive fatalities and injuries, local air pollution prob-lems, and system congestion. To operationalize thisapproach, he made use of indicators in order to identifywhether an area’s transport system was sustainable.


There have been several other proposals for the identifi-cation of indicators of sustainable transport, often in theabsence of a clear definition of what sustainable transportis. One of the leading efforts in this regard was outlined forthe National Science and Technology Council Transporta-tion R&D Committee by Heanue (1997). At the time theindicators under consideration included the following:

1. Market penetration of alternatives to petroleum-based fuels;

2. Transport sector emissions of greenhouse gases;3. Water quality, number of species endangered, soil

protection, and so forth;4. Acres of revitalized urban area and reclaimed

brownfield sites;5. Trip making and miles traveled (by mode);6. Reliance on single-occupant vehicles;7. Access to jobs and services for the transport-dis-

advantaged; and8. Population in areas that attain national atmo-

spheric air quality standards.

The list includes several variables relating to behav-ioral aspects of travel and transport, perhaps with theidea that voluntary action by drivers may be critical inmaking the transport system more sustainable. It is notclear how far this effort went, but it involved severalagencies of the federal government at the time.

Litman (n.d.) proposed a different set of sustainabletransport indicators that is based more on personal orhousehold travel characteristics. The following areincluded in his list of indicators:

1. Average portion of household expendituresdevoted to transport;

2. Average amount of residents’ time devoted tononrecreational travel;

3. Per capita automobile mileage;4. Ability of nondrivers to reach employment cen-

ters or services;5. Per capita land area paved for roads and parking;6. Quality of pedestrian and bicycle facilities;7. Quality of public transit (frequency, speed, safety,

and so forth);8. Special transit services and fares relative to low

income;9. Transit coverage, residents within 0.5 kilometer;

10. Motor vehicle accident fatalities;11. Per capita transport energy consumption;12. Medical costs attributable to transport;13. Publicly financed transport costs; and14. Residents’ role in transport and land use decisions.

Broadly speaking, these are representative of theapproaches that have been taken to define or indicate

what sustainable transport is. Some of the definitionsare narrow, some are broad, and some seek to use indi-cators of the phenomenon, probably with the view ofmoving toward measurement at some point.

NONSUSTAINABLE COMPONENTS OF TRANSPORT

It may make sense to identify some of the phenomenathat are generally accepted as leading the transport sys-tem away from sustainability. We have done this to anextent, but for those unfamiliar with this area furtherdiscussion may be useful.

Diminishing Petroleum Reserves

It is generally recognized that in the 100 or so years ofmotor vehicles using gasoline as a fuel, the world hasconsumed approximately 1 trillion barrels of petroleumfor this and other purposes—all of this at a time whenonly a small proportion of the population of that worldhad access to such vehicles or other uses for petroleumenergy. The major question at this point is, what is thefuture demand for this fuel and will the Earth be able tosupply it? Given that the developing world is expectedto increase its demand for energy in transport and othersectors, which has already begun, global demand willincrease significantly.

What can be said of supplies? The optimist wouldsay that there are about 2 trillion barrels of recoverableconventional petroleum reserves out there. In general,production keeps pace with demand, but if the latterincreases significantly, it is likely that additional pro-duction will have to take place. At present consump-tion exceeds new discoveries by more than a 3:1 ratio.Some scholars believe we have found all of the majorfields in the world. The discovery of more major fields(perhaps in the South China Sea) will probably onlyenable the world to fight a delaying action (Deffeyes2001). Others would say that the conventional sourceswill not last beyond 2020 and that there is significantlymore petroleum out there, but it is found in unconven-tional sources (Greene et al. 2003). Such sources wouldinclude shale oil, oil sands, and tar sands. Estimates arethat shale oil is substantially more expensive to pro-duce and deliver, while the others have costs that arecomparable with those of conventional sources.Depending on what the actual costs are, we will see theslower or faster development of alternative fuels. In thefinal analysis our current transport systems are nonsus-tainable because at least at present they use a fuel thatis finite and nonrenewable. This is true whether we aretalking about conventional or unconventional sourcesof petroleum.

3 7SUSTAINABLE TRANSPORT: DEFINITIONS AND RESPONSES

Global Atmospheric Impacts

Some researchers believe that humans are placing emis-sions into the atmosphere that will eventually haveimpacts on the global climate. Others believe theseimpacts have already begun with increasing global tem-peratures and a rise in sea level. The emissions, some-times called greenhouse gases, may lead to a forcing oran enhancement of the greenhouse effect. This is theeffect that under normal conditions enables the planetto sustain enough heat to make it amenable to life. Morespecifically, the burning of fossil fuels has released sub-stantial amounts of carbon dioxide, a greenhouse gas,into the atmosphere, and this will lead to a forcing or anincrease in the global average temperature. As of 2001carbon dioxide concentrations have increased 31 per-cent over levels in 1750. These levels are now higherthan they have been in the past 420,000 years (Inter-governmental Panel on Climate Change 2001). Trans-portation and the use of petroleum-based fuels areresponsible for just over 20 percent of these emissions asof 2003. This is nonsustainable according to the 2004World Energy Outlook of the International EnergyAgency.

One might reasonably ask whether the warming willcreate major problems or will be only a minor inconve-nience. We really don’t know the answer, but the con-sensus is that the negative impacts of only a minorchange in temperature could be substantial. There is atendency among many sectors to want to ignore theimpacts on the planet. This may be possible for somesectors, but it is not so easy for transport. The floodingof transit tunnels due to a rise in sea level, the failure ofairplanes to take off due to high temperatures, the buck-ling of highways and railroad track due to heat, theflooding of coastal highways and railways, and the sub-mersion of dock facilities are not problems that can bedismissed easily. Even more important is the potentialshift in agricultural production to new areas with mod-erate climates and away from areas that are too hot ortoo dry, which would result in the need to relocate trans-port infrastructure in such areas (Black 1990).

Local Air Quality Impacts

The contribution of motor vehicle emissions to theproblem of poor air quality is significant. This must alsobe seen as something that makes current transport sys-tems nonsustainable. As of 2000, according to theBureau of Transport Statistics, mobile sourcesaccounted for 7 percent of sulfur dioxide emissions, 43percent of nitrogen oxide emissions, 51 percent of car-bon monoxide emissions, approximately 9 percent ofparticulates [2 percent of PM10 (particles up to 10

micrometers in diameter) and 31 percent of PM2.5],and 33 percent of volatile organic compounds. A sub-stantial portion of the production of urban ozone alsohas its origin in mobile sources. The various pollutantsmust be viewed as contributors to nonsustainability, andthey are viewed as such in Europe and by the Organisa-tion for Economic Co-operation and Development(1998). They have not always been viewed as part of thesustainability problem in the United States, but this maybe because these problems were and are beingaddressed. This attitude seems to have changed in recentyears.

The negative health impacts of these emissions, pri-marily on the human respiratory system, must be viewedas a significant problem that cannot be allowed to con-tinue. The United States has made substantial progressin reducing the significance of these emissions, and somebelieve they will cease to be a significant problem in theforeseeable future. Nevertheless, at this time these emis-sions are one of the factors making transport systemsnonsustainable.


It should be an accepted premise that a transport systemthat kills off its users is not sustainable. However, manypolicy makers do not want to include fatalities andinjuries in the calculus of nonsustainability factors. Indi-cations are that the world’s motor vehicle fleet is respon-sible for nearly 1 million fatalities each year andprobably 70 million or more injuries (World HealthOrganization 2001 as cited by Evans 2003). Globalforecasts of fatalities for the next 10 years are almostbeyond comprehension.

Fatalities per vehicle mile are dropping in the UnitedStates, but that is probably due primarily to increases invehicle miles driven. Until recently total fatalities werealso dropping, but the latter appear to be increasingnow or at least leveling off. We are no longer sure whatis happening with injuries.

Congestion

Policy makers in general do not view congestion as amajor barrier to transport sustainability. Even this con-ference is giving it rather short shrift. The reason is notat all clear, although it may be attributable to the indi-rect nature of the impacts generated. Congestiondecreases the speed of vehicles and results in lower fuelefficiency. It increases emissions that are detrimental toboth the global and the local environments. It increasesmotor vehicle incidents, while it decreases fatalities. Per-haps it was viewed as a manifestation of all the other


criteria leading to nonsustainability and its inclusionseen as redundant.

Several years ago at a Transportation Research Boardannual meeting the following question was asked: If weadopted a renewable transport fuel with zero harmfulemissions, would we have a sustainable transport sys-tem? The question was never answered, but it is onethat must be asked again. Clearly, if hydrogen was thefuel, our concerns about the depletion of fuel stockswould be removed, as would the problems of globalatmospheric impacts and local air quality. Fatalitieswould also be reduced, since motor vehicle accident fireswould be eliminated in the case of a hydrogen fuel.However, we would still have the problem of congestionin urban corridors and increasingly on major Interstatehighways, and this, and eventually gridlock, must cer-tainly be viewed as contributing to nonsustainability. Sothe answer to the question is that even a wonder fuelwould not make the transport system sustainable. Wewould still have congestion, which threatens only to getworse in the coming decades.

Noise

One major difference between sustainable transport inthe United States and sustainable mobility in Europe isthe latter’s concern with noise. There is a wealth of lit-erature suggesting that loud noise and continuous noisecan be harmful to human health. The harm may be psy-chological and result in nervousness and behavioral dis-orders, or it may be physiological and result in impactsas significant as heart disease from the excess produc-tion of adrenaline. Many European nations are attempt-ing to lessen the level of noise, particularly in urbanareas. Of course, the same reactions are inherent in thetransport systems of North America, and researchersare trying to minimize them. However, the problem andreactions to it are rarely viewed as part of the criteriamaking transport nonsustainable here. The density ofcities and urban activities in Europe undoubtedly makesthis factor more significant.

Biological Impacts

Much attention has been given to the need to protectbiological resources from the damage created by trans-port activities (Transportation Research Board 1997).Animals killed along highways [estimated to be between4 million and 6 million annually (Black 2003)]; riversand streams polluted and marine animals killed byrunoff from highways, runways, and the like; and plantsdestroyed by emissions are all representative of thesebiological impacts.

Perhaps the most devastating transport incidents interms of biological resources are the tankers that breakup and spew thousands of gallons of oil into the ocean orwaterway they are traversing. Marine animals andwaterfowl are often the most visible victims of such inci-dents on the evening television news. At the same timewe must realize that these are local impacts—severe, butlocal. We have never lost a species because of an oil spill.It is far more likely that we will eliminate a species ofmarine life through overfishing than through operationsin the transport sector.

Although we are not at risk of losing biological speciesbecause of the nonsustainability of transport, there is nodoubt that transport impacts in this area are significant,as evinced by Forman’s Road Ecology (2003) and the1997 report Toward a Sustainable Future (Transporta-tion Research Board 1997). The latter report focused onclimate change and ecosystem impacts, results of one ofthe narrower definitions of sustainable transport.

Equity

Other researchers have looked at the question of whatmakes the transport system nonsustainable, and in sodoing they have focused on the equity of the earlier defi-nitions (Litman 1999; Feitelson 2002). Some of thesedefinitions dealt with the notion that operations on thecurrent transport system should not jeopardize the pos-sibility of future generations satisfying their transportneeds. This is not meant to imply that future generationsshould have the same type of transport system that wehave today, although some have read it that way. It sim-ply means that if we are going to continue with a systemthat is based on finite petroleum reserves, then we shouldhave another fuel available for those future generations.This is what is meant by transgenerational equity.

It also is believed by some that if the transgenera-tional argument is acceptable, then the current trans-port system should be equitable. An equitable transportsystem would be one that is fair, impartial, and just.Contrary to popular belief, it has nothing to do withtransport facilities being equally accessible or availablefor all potential users. To think so is to confuse incomepolicy with transport policy. It is clear that these ques-tions have not been dealt with enough in the transportliterature, and perhaps we will get better insight intothese aspects of sustainable transport in the near future.

IMPACTS OF THE DEFINITIONS ON HOWTRANSPORT SUSTAINABILITY IS ADDRESSED

In certain ways the definition of sustainable transport isextremely important. This is particularly so if multina-


tional regions, nations, states, and urban areas allow thedefinition selected to guide all of their actions in therealm of sustainability. It is unlikely that many areaswould do this, but there is some belief that many of thedefinitions involve controlling problems that are a func-tion of the amount of travel that takes place. Some localareas might see the best approach to sustainable trans-port as one that involves decreasing the level of vehiclemiles traveled. The general problem is more complexthan a single-variable approach can handle.

A more fundamental question would be, what isbeing done to address the problems preventing the cur-rent system from being sustainable, whether one placesthe problems in that context or not? In this regard thereis reason for some optimism.

Diminishing Petroleum Reserves

Diminishing petroleum reserves are being addressed inseveral ways. These are not necessarily planning based,and I will return to that later. Since the 1970s we havehad corporate average fuel economy standards and thegas guzzler tax, both intended to encourage motor vehi-cle manufacturers to produce cars that use less fuel perunit of distance traveled. Recently the average miles pergallon has begun to drop, which may be attributed tothe increasing number of sport utility vehicles in thevehicle fleet. Nevertheless, the fuel savings since themid-1980s are notable.

Another major improvement in this area is the devel-opment of hybrid (gasoline–electric) vehicles such as theHonda Insight and the Toyota Prius. They significantlyincrease fuel economy, although not by as much as somemay have hoped.

Development of alternative fuels is perhaps whatmost people believe will be necessary in response todiminishing petroleum reserves. On this front the newsis not quite so good. Hydrogen is the promising alterna-tive to petroleum-based fuels, but it is still far too expen-sive to produce at a price that will be competitive withgasoline. Ethanol is also not a major alternative now,and it is unlikely to have a major role in the future. Asidefrom subsidies needed to make it competitive, it usesland that might better be used for food production.

The motor vehicle industry has introduced differentintelligent transportation system technologies into vehi-cles that should prevent drivers from getting lost. Mostnotable here is the combination of geographic informa-tion systems and the Global Positioning System, whichdecreases wasted travel.

Planners are not able to do a great deal in this areabeyond the obvious attempts to allow certain commer-cial facilities (e.g., grocery stores) to be more ubiqui-tous, which would result in less driving and fuel use.

This may require zoning changes in many communities.To the extent that planners have input into the process,they can encourage the development and improvementof public transit facilities that promise to remove somedrivers from streets and highways. Programs thatencourage carpooling would also be useful in somecities.

Global Atmospheric Impacts

The principal global atmospheric impacts from thetransport sector are emissions of carbon dioxide and theescape of chlorofluorocarbons (CFCs). The former are asignificant portion of the carbon dioxide emissions fromall sectors. The Kyoto protocol was intended to set lim-its on these emissions for most of the developed nationsof the world, but the United States refused to sign on tothe protocol. More recently, some European nationshave begun to sound as though they will back awayfrom it.

Carbon dioxide and some trace gases are collectivelyreferred to as greenhouse gases. It is generally believedby the scientific community that emissions of these gaseswill cause a warming of the planet and that this in turnwill lead to melting of some middle-latitude glaciers andupper-latitude ice cover, and that this melting along withthermal expansion of the oceans will result in a rise insea level. The ramifications of these changes run thegamut from losses of viable crop production areas tochanges in the currents of oceans.

Planners and local areas have not done a great dealabout this problem as such. If they advocate some of themethods of decreasing fuel use noted above, they will beable to decrease carbon dioxide emissions, which arecurrently running at about 20 pounds of carbon dioxideper gallon of gasoline burned.

California has enacted legislation that will requireautomobile manufacturers to produce motor vehicleswith significantly lower carbon dioxide emissions by2010. Legal challenges to the statute are likely, but if itcan withstand them several eastern states are likely toadopt similar laws.

The major concern with regard to CFCs is that theywere creating holes in the ozone layer surrounding theplanet. The holes increased the amount of ultravioletradiation reaching the surface, which would lead toproblems ranging from disturbances to the ocean foodchain to an increase in human skin cancers and eye ail-ments.

CFC emissions have plummeted since the end of1995, when the Montreal protocol brought a swift endto the production of this coolant–solvent. Some CFCsstill escape into the atmosphere from older automobiles,but this is probably not significant as we approach the


ninth anniversary of the withdrawal of CFCs from themarketplace.

It would be misleading to think that the problems ofthe ozone layer have been solved. Emissions of CFCs setin place a chain reaction that continues today. We can-not be certain when it will cease, although a couple ofdecades has been suggested.

Local Air Quality Impacts

Significant strides have been made in this area because ofthe fuel emission standards of the U.S. EnvironmentalProtection Agency. Laws requiring reductions in emis-sion levels have also been enacted. They have been suc-cessful in reducing the levels of nitrogen oxides, sulfuroxides, volatile organic compounds, carbon monoxide,and particulates. Levels of CFCs (found in automobileair conditioners) and lead in gasoline have been reducedsignificantly.

Acid deposition is a product of nitrogen oxide andsulfur oxide emissions. The transport sector’s contribu-tion is not significant. Although convection does allowsome tailpipe emissions to become contributors to whatbecomes nitric and sulfuric acid “rain” and this in turnleads to biological and economic impacts, this is oneproblem that seems to be improving.


Significant improvements in the fatalities and injuriesarea have been made over the past 40 years. Fatalitieswere in the 50,000-plus range during the 1960s, and wehave seen improvements during the past several yearsthat place this number nearer 40,000.

Between 1999 and 2004, the fatality rate per 100 mil-lion vehicle miles traveled decreased from 1.50 to 1.46(www.dot.gov/affairs/dot10605.htm). In March 2004 theUnited States set a national target of a 33 percent reduc-tion in fatalities in the next 4 years. The reduction isexpected to occur through increases in seat belt use,stronger enforcement of drunk driving laws, and hours ofservice regulations for motor carriers. The target isachievable. Other countries have set more ambitious tar-gets (e.g., Sweden has set a target of zero fatalities), butthe action taken by the United States is a significantimprovement over prior goals that have been set. Mostother countries have not established any goals in this area.

Congestion

Local planners and engineers have a significant influenceon the problem of congestion. The placement of demand-

responsive signals, lane designations, highway expansion,parking control, and a host of other factors can be and arecontrolled at the local scale by these individuals. They mayalso be influential in getting local establishments to allowmore flexible arrival and departure times and thereforeenabling a flattening of the a.m. and p.m. travel peaks. Inaddition, they are able to assist with the creation andmaintenance of carpooling and similar operations.

Although congestion appears to have almost leveledoff in the past few years, there is no reason to assumethat this will continue. Therefore, it is likely that some-thing more will have to be done. Interesting technolo-gies are possible in this area (e.g., electronicallyconnected convoys), but expense will probably preventtheir appearance in the near term.

Noise

Transport noise exists in some communities in the UnitedStates. The problem is usually combated with the con-struction of sound-absorbing walls or similar structures.In parts of the world where the human landscape waswell established before the arrival of motor vehicles, thisis not as easy to do. Europe and parts of Asia have sig-nificant noise problems. Some experimental work isbeing done with sound-absorbing highway pavements,but it remains to be seen whether they will help in areaswhere the individual cars are relatively quiet but the totalnoise generated in a traffic stream is significant.

The problem is not as bad in North America as inEurope, partly because of the lower density of settle-ment, which enables highways to be placed at some dis-tance from residential areas.

Low Mobility

Low mobility is as much a problem with sustainabletransport as very high mobility. The provision of mobil-ity is a key provision of several definitions of sustainabletransport. Localities can increase mobility levels for theirresidents by making sure that transport facilities areavailable to all members of the community. They can dothis through providing regular urban public transit, ruraltransit, or specialized transit (for the handicapped andothers). Funding for such operations is often difficult toobtain, and a recent work (Ubbels et al. 2004) examinesmany alternative mechanisms in this area.

Biological Impacts

Transport facilities and operations can affect animaland plant life. In some cases the impacts involve destruc-


tion of local species or the loss of habitat. In other casesthey involve expansion or contraction of species or theintroduction of new species that may be harmful toexisting organisms in an area. The latter usually occurswith plant introductions in urban and rural areas.

Highways have become the major cause of deathamong numerous animal species, and there is little rea-son to assume that this will end in the near future. Whilesuch impacts are often local and not detrimental to anentire species, it is nevertheless desirable that we try toprevent them. Some may argue that they cannot be pre-vented effectively, but numerous local projects involvingtunneling under highways to provide a safe route foranimal movements would counter this argument.

Equity

What could be and is being done to foster an equitabletransport system now and in the future is not as easy toidentify. It should be apparent that anything improvingthe situation with regard to the aforementioned defini-tions will contribute to transgenerational equity. Withregard to the contemporary situation, it is not as clearwhat can be done, although to accept the transgenera-tional equity argument one must assume that it appliesto the current scene as well.

Solutions to the various problems noted here wouldprobably move toward a more equitable system, butsome might argue this point. Their argument wouldprobably go to the very nature of what is meant by anequitable transport system.

FINAL CLARIFICATION AND COMMENT

The careful reader will recognize that all of the pro-posed attributes of a sustainable transport system havenot been reviewed here. The primary reason is the hostof definitions offered. For example, the Mobility 2001definition includes the ability to communicate, andTransport Canada’s 2003 definition includes the “high-est possible standards for security.” Both may be desir-able, but they are not necessarily components of asustainable transport system.

If we want to strive for a sustainable transport sys-tem, we cannot weigh it down with every possible desir-able attribute. This does not mean that these variousother items cannot be pursued under the umbrella ofsustainability, but let’s not set the bar so high that intime participants simply throw up their arms and walkaway. I am reminded of President Kennedy’s 1962 trans-portation address to Congress, wherein he proposed aprogram for urban mass transit to stave off whatappeared to be the rapidly approaching end of urban

transit in the United States. The program put in placewould have accomplished this, but soon transit systemswere proposed to alleviate congestion, solve air qualityproblems, provide access for disadvantaged groups, andserve areas outside the original urban area. So manyrequirements were placed on urban transit that it couldhardly satisfy them, and many view those investmentstoday as largely unsuccessful. These systems are still inplace, but I would not credit the goals and objectives oftheir creation for this. My concern is that we will try todo so much with our transport system under the rubricof sustainability that we will make the concept unwork-able, to the detriment of current and future generations.

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4 4

What Are the Challenges to Creating Sustainable Transportation?How Can Transportation Systems Become More Sustainable?

Martin Wachs, University of California at Berkeley

“Sustainability” has become one of the watchwordsgoverning policy deliberations and debates abouttransportation. The intensity with which sustain-

able transportation will be debated is likely to increasefor decades to come. Like so many other words thathave entered our vocabulary, such as “efficiency” and“equity,” the concept is powerful and evokes strongreactions even as it is difficult to define and measure.William Black’s paper has given us an intellectually richoverview of the concept of sustainability and the chal-lenges that the concept poses, and other speakers havegiven us benchmarks that help us gauge the depth andbreadth of the sustainability challenge. My goal is toprovide a bridge between the morning overview and thebreakout sessions that will follow this talk. More specif-ically, I will assess how transportation planners, policymakers, and public officials can take actions that willmove us along a path toward sustainability. Because ofthe complexity of transportation as a human activityand as a physical network, we need to talk about actionsthat can be taken in the public sector, by private compa-nies, and by individual citizens and households. Despitethe importance of sustainability internationally, I willfocus on sustainability in the United States to simplifythe discussion and in recognition of our personal rolesand organizations. I will draw on some insights fromexperience overseas.

On balance, the ability to travel and to ship goods atlow cost over long distances, as provided through acomplex of transportation systems and networks, hasenhanced humankind’s economic, social, and personalwell-being. It has been a major factor in increasing

access to health care, education, employment, and recre-ation, and improved access to a wider range of con-sumer goods has dramatically improved standards ofliving all over the globe. However, we are genuinely con-cerned about sustainability because of the growing dis-parities between those who have achieved these benefitsand those who have not yet but certainly hope to in thefuture. The differences are especially noticeable becausethey exist at the same time that many are becomingaware that the worldwide stock of energy resources pro-viding for mobility is being depleted at a rapid rate. Wewish to reduce reliance on those limited resources whileexpecting increased mobility for a large proportion ofthe world’s population. At exactly the same time thatconcern is growing with respect to the distributionalaspects of mobility and the long-term depletion ofenergy resources, the atmospheric concentration ofgreenhouse gases (GHGs) is growing ominously, andscientific evidence has persuaded most of us that this iscausally related to global energy consumption. Also, thenegative byproducts of mobility in the form of air andwater pollution, contamination of land, and the accu-mulation solid wastes are causing many to worry thatthe benefits of mobility may be less available to futuregenerations, while the costs of today’s mobility may beescalating dramatically.

To acknowledge these concerns in no way requires usto belittle the significance of the benefits of transportsystems. The sustainability movement is a search forbalance, and the attainment of balance between mobil-ity and sustainability is an enormous challenge. Whilesome will emphasize one side of the scale more than the

other, it is simply too easy to dismiss the importance ofmobility in favor of sustainability and similarly too easyto deny the unsustainability of current global patternsof mobility and energy use. The real challenge lies in therecognition that both are critically important policygoals. The European notion of “sustainable mobility”suggests a search for balance, and that is why we arehere. Our community is by no means unanimous in itsperceptions of either the benefits of mobility or the costsof a mobility-dependent society or even about the defin-ition of sustainability, but sustainability is here to stayas a subject of public debate and policy making. I hopewe can make a contribution to clarifying that debate,but I hope even more strongly that we can influence thedevelopment of policy through our discussions at thisconference.

PARALLELS WITH EARLIER ENVIRONMENTALAND AIR QUALITY MOVEMENTS, AND A PREDICTION

Everything we do is in many ways the direct product ofwhat came earlier. The current movement for sustainabletransportation is not at all discontinuous with the historyof transportation policy. We should, therefore, try to learnfrom that history. For example, in the late 1960s in theUnited States we were at the height of the national free-way building period that has now ended, and we werejust starting to formulate a national program of capitalinvestment in public transit. We tried at that time to findthe right balance between mobility and environmentalconcerns, and the process was not at all easy.

Imagine for the moment that mobility had grown asmuch as it has since 1970 and that we had not as a nationadopted the National Environmental Policy Act of 1969(NEPA). While we have certainly not eliminated the neg-ative environmental impacts of transportation, our soci-ety is better off as a result of the passage of NEPA, evenif we can think of many shortcomings in the NEPAprocess. Remember that NEPA was highly controversial,and many in the transportation community thought atthe time that it would destroy our effort to create a moremobile society. In retrospect that fear was certainly notrealized. As a result of NEPA, which has proved to beenormously robust by surviving thousands of legal andpolitical challenges, we now incorporate environmentalimpacts of transportation more explicitly into the plan-ning process at every stage. Transportation agenciesemploy environmental specialists and engage in commu-nity interaction much earlier in every planning, design,and engineering activity. NEPA helped to create a bal-ance that in retrospect appears far more appropriate andless revolutionary than it did at the time. To a large num-ber of people, the environmental impacts of many trans-

portation projects are still intrusive and unacceptable;the law has been dramatic and its results have beenextensive, but it has redirected and not prevented invest-ments in improved mobility.

Imagine for the moment that mobility had grown asmuch as it has since the first air quality act amendmentsthat affected automobile travel. In looking back on whathas happened with respect to air quality over the past 30or 40 years, most agree that we are much better off todaythan we would have been were automobiles producingas much pollution as they did in 1970. While we havecertainly not eliminated urban air pollution and itshealth impacts, and our standards only recently havebecome more demanding because of improved under-standing of the health effects of certain pollutants, fewquestion that society is better off as a result of regula-tions that control air pollutant emissions and concentra-tions. The series of legislative actions taken with respectto air quality, like those associated with NEPA, werehighly contentious. Many false starts were made, andonerous regulations were enacted and then amended.But, once again, contrary to the expectations of many,the results of NEPA and of air quality regulation havebeen enormous. They have redirected and not preventedinvestments that have improved mobility.

Imagine for the moment that it is now 2040 and thatpersonal mobility and goods movement have grown asmuch as they were predicted to grow in both developedand developing countries. Looking back on what hap-pened with respect to sustainability, I venture to say thatwe could not in 2040 imagine what the world would belike had the concept of sustainability not been acted onin the interim—for example, had levels of energy usedper unit of transportation in 2004 prevailed up until thisdate. It will probably have proven impossible to providethe world with completely sustainable transportation,and new knowledge will have caused us to develop newdemands and limits that we cannot conceive of in 2004.Nevertheless, the contentiousness of today’s debates willhave paled, and attention to improved sustainabilitywill have redirected but not prevented investments inimproved mobility.

AWARENESS OF SUSTAINABILITY IS GROWING,BUT THE UNITED STATES IS LAGGING BEHIND

Though sustainable mobility is becoming a more widelyshared goal, we are still in the early stages of organizingsocietal action toward meeting that goal. It would bewrong to think that we have little or no interest in orcommitment to sustainability. Actions are being takendespite strong differences of opinion and some confu-sion. However, society is complex, and that complexityis one of the most important sources of our apparent

4 5WHAT ARE THE CHALLENGES TO CREATING SUSTAINABLE TRANSPORTATION?

inertia. Furthermore, sustainability remains a broad andvague concept, and that contributes to our inertia.

Within the European Union there is a strong impera-tive to achieve the 8 percent GHG reduction targets setby the Kyoto protocol, and some countries haveembraced the goal to exceed the Kyoto targets by quitea margin. In contrast, of course, the United States hasrefused to sign the Kyoto accords. Transportation-basedemissions in the United States (about one-third of allemissions of GHGs) are rising at about 3 percent peryear, while emissions from residential and commercialsources are rising even more rapidly (Banister andPucher 2003). Even if these trends cannot be reversedfully, their direction and speed must be changed, and Ihope that we can proceed into the workshops unified inthis commitment.

Despite the reluctance of the federal government totake responsibility for GHG reduction, there has beenmuch activity in the United States in pursuit of sustain-able mobility. A recent survey by staff members at theVolpe Transportation Center found that as of May 31,2001, a surprisingly large number of states—25 statesplus Puerto Rico—had initiated the process of develop-ing statewide GHG reduction plans and that 19 hadcompleted those plans. In addition, 134 cities and coun-ties had, by that date, initiated voluntary GHG planningactivities, which, at a minimum, include commitmentsto pass supportive resolutions, conduct baseline esti-mates, develop action plans, and monitor results (Lyonset al. 2003). After reviewing this national pattern, theauthors studied a subsample of these programs in depth.The following were among the most interesting and use-ful conclusions with implications for our discussion:

• Local and regional agencies often act out of therealization that they stand to suffer damage themselvesfrom global climate change unless trends are reversed.The recognition that they might themselves suffer fromrising water levels, negative impacts on tourism, anddamage to forests was often associated with interest indeveloping plans for GHG reduction.

• Local governments that adopted a formalapproach, with goals, deadlines, inventories, and fore-casts, tended to be more effective than those that werewell meaning but less focused.

• Planning was more often undertaken where GHGreduction was seen by state leaders to contribute toother ongoing state plans and programs, such as eco-nomic development and smart growth. In other words,where there was a strong tradition of environmentallyresponsible planning and the perception of complemen-tarity with other planning efforts, sustainability plan-ning had a better chance of being adopted.

• Planning was far more often undertaken whereone or more political champions took a leadership role.

Virtually all the successful plans occurred in placeswhere mayors, governors, legislators, or other leaderschampioned their development and saw them throughto completion.

• Transportation agencies were rarely the initiatorsor the lead agencies in preparing such plans. More oftenthe lead agencies had responsibilities for energy, envi-ronment, or land use. While transportation agencieswere often not in the lead and often lagged behind othersectors, the most successful plans resulted from multi-agency collaboration.

It would be a mistake to conclude that there is littleor no corporate interest in a more sustainable future.Much work is taking place in the private sector. As oneexample, for the past 4 years under the sponsorship ofthe World Business Council for Sustainable Develop-ment, 12 leading international automotive and energycompanies have worked together to consider howglobal mobility patterns might evolve through 2030 andbeyond and have attempted to identify strategies tomake transport more sustainable. Though we mayremain skeptical about the motivations of these corpo-rations, the seven goals identified by the study team arecompletely consistent with the view of sustainabilityenumerated by William Black in the opening paper forthis conference:

• To reduce conventional emissions from transportso that they do not constitute a significant public healthconcern anywhere in the world,

• To reduce GHG emissions from transport to sus-tainable levels,

• To reduce significantly the number of transport-related deaths and injuries worldwide,

• To reduce transport-related noise,• To mitigate traffic congestion,• To narrow “mobility divides” that exist within all

countries and between the richest and poorest countries,and

• To improve mobility opportunities for the generalpopulation in developed and developing societies.

The report Mobility 2030 (World Business Council forSustainable Development 2004), now in the final stagesof preparation for release, addressed all of these goals,but at different levels of depth and specificity. It gavegreatest emphasis to and its most specific recommenda-tions address power train technology, fuels, and energyissues. This is certainly understandable given the compa-nies that have been involved. Still, the fact that a studytook place and that a comprehensive set of sustainabilitygoals has been developed by the companies is itself anindication that sustainability can become a major factorin private-sector planning, research, and marketing.


TAMING THE COMPLEXITY OF SUSTAINABILITY:SETTING PRIORITIES

Societies do not do well with complexity, nor in all like-lihood do workshop conferences like this one. We needto find a way of reducing our discussion to manageablecomponents, just as we need to find ways of enactingpolicies through manageable steps and workable com-ponents. We need to acknowledge complex relation-ships among the elements while focusing on them one ata time. We only seem to be able to enact laws and regu-lations, to take actions, and to set priorities one bite ata time. Even if we limit our discussion to the UnitedStates, which is in itself an enormous oversimplificationof what needs to be done, we will not be able to addresssimultaneously all the dimensions of sustainability dis-cussed so far at this meeting. We certainly will not beable to do so at all levels of government and within theprivate corporate sector and at the household level. Yeteventually sustainable transportation will requireresponses on all those dimensions and from all thoseactors.

I propose that our workshop discussions considerpriorities for the coming decade while acknowledgingthat priorities will certainly change over time. Weshould consider how the various actors might con-tribute to sustainability most productively over thatperiod. I have tried to illustrate the nature of the com-plexity we are facing in Figure 1, which presents the twodimensions of sustainability that I just mentioned. I rec-ognize, of course, that the figure is a gross oversimplifi-cation of anything that might happen in the real world,

but I still think it might facilitate dialogue in a numberof ways.

One way of using a matrix like this would be toassign priority weights to a particular intersection ofactors and elements. For example, one of us might thinkthat the depletion of energy reserves is extremely impor-tant and that it should fall to the national governmentto play a large role, so a high score might be placed inthe box where the national government row intersectsthe energy reserves column. Similarly, one might thinkthat traffic congestion is an important public policyproblem but that it is not really important to global sus-tainability and is primarily a problem that should beaddressed by local and regional governments. Thismight be reflected by a moderate score in the boxformed by the intersection of the traffic congestion col-umn and the local government row, while zeros areentered in some of the cells elsewhere in that column.

Another way in which a matrix could help us orga-nize our thoughts would be to fill into each box a fewactions or strategies that might be most effective if takenby a particular actor (row) with respect to a sustainabil-ity element (column). For example, we might think thatpricing would be an appropriate strategy by which stategovernments (row) could address congestion (column),while we might think that traffic safety (column) mightbest be addressed at the national level (row) throughregulation of vehicles.

I offer this suggestion as a way of grabbing hold of amonster while recognizing that the issue remains enor-mously complex and that the elements of the matrix areindeed highly interrelated.


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FIGURE 1 Complexity of sustainable transportation.

KEY QUESTIONS DETERMINING THE FUTUREOF SUSTAINABLE TRANSPORTATION

Indicators of Sustainability

A prerequisite to progress toward sustainable mobilityis the development of a set of quantitative indicators bywhich to measure progress over time. American societyalready uses a wide variety of quantitative indicators ofour well-being, and policy makers have become accus-tomed to responding to notable shifts in indicators overtime. The best examples of indicators on which we relyin policy making undoubtedly are economic indicators.Such variables as unemployment rate, consumer priceindex, housing starts, and numerous others are used reg-ularly to measure current conditions and changes inconditions over time. Interpretations of patterns amongthese indices differ, of course, and such differences arethe basis of policy debates. Indeed, the differences ininterpretation and the differences in policy recommen-dations suggested by the indicators are what make themmost valuable. Indicators must be carefully chosen onthe basis of their long-term policy relevance, inter-pretability, and implications for the collection of rele-vant and accurate information. If useful sustainabilityand mobility indicators can be developed, they mighteventually be used to test and model the likely impactsof different policies on indicator values and thereby tointerpret their impacts on sustainability. In the work-shops we might agree that sustainability indicators arenecessary to the development of policies that promotesustainable mobility and that we might then concentrateon the nature and content of appropriate indicators.

The matrix introduced earlier makes it clear thatsome dimensions of sustainability, like GHGs, are mostrelevant because of their effects at the global scale. Oth-ers, like noise, can really only be measured and con-trolled effectively at the local scale. It would be helpfulfor our workshops to recommend indicators that oper-ate at different levels and to discuss the sources of datathat might be used to operationalize them. In the shortterm, given the current state of evolution of transporta-tion policy, the most important indicators of sustain-ability are those that could be operationalized at thestate and national levels. Those indicators would dealwith levels of mobility, energy and resource consump-tion in transportation, and the production of GHGs andother waste streams.

Technological Changes

Most observers of transportation planning and policyagree that most of the progress made in the past 40 yearstoward lessening the environmental damage done by

transportation has resulted primarily from technologi-cal change. Dramatic reductions in tailpipe emissionsper mile of driving have led to equally dramaticimprovements in air quality in some of our most pol-luted metropolitan areas even as the number of tripsand vehicle miles of travel have grown substantially.Fleet fuel economy has improved as well, though per-haps less dramatically, and improvement has been slow-ing in recent years. These technological changes, ofcourse, are not independent of political decision mak-ing. They are the result of regulation, mostly by the fed-eral government but in some cases also by states,particularly states like California, which have hadsevere environmental problems to address. Most believethat changes in vehicle technology and fuels have beenmore influential than changes induced by regional trans-portation planning or changes in individual and house-hold behavior. It follows that government regulationsaffecting technology have been far more influential andeffective than government planning requirements or ini-tiatives to change travel or residential location behavior.Should we, as a group, conclude that past patterns are agood predictor of the future, and therefore that the mostpromising approach to sustainability is through techno-logical change? Or should we conclude that the attain-ment of sustainability requires a dramatic escalation ofchange and that technology alone will be unable tomove us onto a path toward a sustainable transporta-tion system?

Some will attempt to set limits on the role of techno-logical change in approaching sustainability on the basisof moral judgments and positions that are strongly heldfor ideological reasons. I believe that technology will playa major role in sustainability policy because we are ableto identify changes in technology that will improve mobil-ity and enhance the quality of life while reducing the foot-print left by human activity on the natural environment.As long as this is the case, technology should and willplay a central role in the pursuit of sustainability.

But there are limits to our ability to rely on techno-logical change. We must note that some of the potentialbenefits of improved engine efficiency and better fueleconomy have been lost because manufacturers haveproduced and consumers have opted to buy vehicles thathave grown larger and that include many energy-con-suming options. The benefits of improved technologyhave, to some extent, been converted into larger, faster,and more luxurious vehicles rather than into vehicleshaving more modest performance features and dramat-ically improved fuel efficiency. Many American manu-facturers, instead of focusing on smaller cars that aredramatically more fuel efficient, are promoting theirforthcoming entries into the market for hybrid vehiclesas bigger and more luxurious cars that get the same fueleconomy as smaller cars.


Regulation Versus Market Forces

One of the ongoing debates in American policy makingis whether market forces are sufficient to bring abouttechnological and behavioral changes needed to achieveenvironmentally responsible mobility and eventually toapproach sustainability. Clearly, for example, as suppliesof energy become more limited prices will shift, and thiswill induce changes in consumption patterns and tech-nologies. Key questions concern whether market forceswill be sufficient or whether they need to be coupled withfederal and state regulations. In the past, the corporateaverage fuel economy regulations that were part of theEnergy Policy and Conservation Act and the tailpipeemissions standards and National Ambient Air QualityStandards required by the Clean Air Act Amendmentshave been controversial because they have attempted toforce technological change. The California Air ResourcesBoard, for example, last month introduced draft regula-tions in compliance with the state’s S.B. 1493 that wouldrequire a reduction in vehicle carbon dioxide emissionsstarting in 2009 and amounting to a 30 percent reduc-tion in new vehicles by 2015. The New York Times(Hakim 2004) recently reported that New Jersey, RhodeIsland, and Connecticut are considering the adoption ofsimilar regulations.

The appropriateness of direct government regulationversus greater reliance on market forces is a topic thatcould lead to some lively discussions in the workshopsessions. The case for centralized regulation has beenwell made over and over again by environmental andpolitical philosophers such as Garrett Hardin and AldoLeopold, who have shown that regulation is neededwherever resources are owned or controlled in commonon behalf of communities. While many government reg-ulations have been highly imperfect and some can beshown to have induced inefficiencies and inequities, itseems inevitable that regulation will play a central rolein our quest for sustainable mobility. The challengebefore us is to devise regulations that complement otherapproaches to achieving sustainability and that mini-mize unintended negative consequences. A great deal ofanalysis is needed in support of a program of regulationthat produces a substantial excess of benefits over costs.

Direct Regulation of Travel Behavior

In America, we have found it politically feasible to reg-ulate vehicles and fuels, and these regulations have cer-tainly in turn affected consumer behavior. However, wehave shied away from measures that were seen to beregulating households and individuals more directly.Under the requirements of the Clean Air Act Amend-ments, government attempted to regulate commuter

choices through the Employee Commute Options Pro-gram and, for example, attempted to “cash out” freeparking. While these initiatives have often been techni-cally successful at a limited scale in improving vehicleoccupancies and shifting commuters in measurablenumbers to public transit or carpools, corporate andpolitical objections to such programs have caused themto be viewed widely as less than successful, and in mostcases eventually they have been abandoned. Should we,as a group, conclude that the attainment of sustainablemobility in the future requires more vigorous and directregulation of travel decisions at the household and indi-vidual level, or should we conclude that such anapproach is likely to be politically unacceptable in theUnited States for some time to come? It is my expecta-tion that for the foreseeable future it will prove moreappropriate and more feasible for political reasons toregulate vehicles, fuels, and emissions than to regulatepersonal or household choice making.

Still, we need to learn to be more clever and subtle inour use of regulation to achieve intended social pur-poses. Jonathan Levine’s research, for example, showsthat more conservative Americans often assert that it is“market forces” and “personal preferences” that leadus to prefer low-density single-family homes in areascharacterized by single land uses. He disagrees, pointingout that often market forces and household preferencesactually would lead to higher densities and communitiesconsisting to a far greater extent of mixed land usesexcept for the fact that they are excluded by zoning andsubdivision regulations prohibiting those land uses andrequiring the traditional American suburban land usepatterns. Those regulations were in many cases put intoplace decades ago to keep residences away from heavyindustries. Today they inhibit rather than enhance ourability to achieve more current versions of appropriateland use mixes that support sustainability. The lesson tobe learned is that regulation must be sensitive to theneed for a range of human choices. This may suggestthat the most appropriate regulatory strategies are thoseenhancing our choices among alternatives by focusingon performance measures related to policy outcomesrather than those limiting our choices directly (Levine etal. 2005).

Pricing

The use of pricing to influence travel behavior is closelyrelated to the direct regulation of behavior, since one ofthe most direct ways of regulating behavior is throughthe setting of prices. Many have advocated for decadesthat pricing transportation programs differently couldbe among the most promising ways of approaching sus-tainability. Empirical evidence, particularly from inter-


national experience, supports this expectation. Taxes onnew vehicles in Europe and some Asian countries doresult in lower vehicle ownership rates, even whereincome levels exceed those in the United States. Whilevehicle ownership rates are growing in most of thosecountries, they remain substantially lower than in theUnited States. Consistently higher taxes on vehicle fuelsin many other countries continue to be associated withthe purchase of smaller and more fuel-efficient vehiclesthan in the United States. And where vehicles and fuelsare more expensive, higher proportions of trips aremade on public transit and by bicycle and walking thanare typical in the United States, even where incomes arecomparable. Yet American policy makers have beenreluctant to attempt to price the externalities of trans-portation systems directly or even indirectly, or to usetaxes as policy instruments for changing transportationbehavior. Should we, as a group, conclude that morevigorous pricing of transportation is necessary andappropriate to bring about sustainable transportation,or are we reluctant to promote that direction of changein American policy? I expect that pricing strategies arebecoming more politically acceptable than they havebeen in the past, for three reasons that I have developedelsewhere. First, there is an increasing need for revenuesin support of transportation programs as traditionalreliance on the fuel tax produces reduced revenue inrelation to perceived needs. Second, the increasinglywidespread deployment of a variety of automated andcomputerized mechanisms by which to collect pay-ments, such as FasTrack and E-ZPass, is making it phys-ically easier to collect transportation system use-relatedcharges in a variety of situations. Finally, growing famil-iarity with prices and collection mechanisms is reducingconcerns on the part of the public that such approachesare improper or that they constitute violations of theprivacy of the traveler (Wachs 2005).

Individual Education

There is an enormous variation in travel behavior withinAmerican society, and we may conclude that this varia-tion results, at least in part, from widely different atti-tudes. A few, for reasons that vary from personalpreference to deep moral commitment, have chosen tobe carless. These individuals rely much more heavilythan others on public transit, walking, and cycling. Oth-ers, who would not think of rejecting automobiles, ownmotorized vehicles but consciously choose fuel-efficientones such as hybrid cars. Where such behavior does notunduly complicate their lives, they cycle, walk, or usepublic transit for trips. Still others own multiple fuel-inefficient vehicles and regard it as irrational, futile, orunnecessary to alter behavior through direct personal

action when public policy does not demand or rewardsuch behavior. This variation in attitudes, commitment,and behavior is in need of deeper study and analysis.Some believe that public education is the key to sustain-ability. Those holding this position cite precedents inother areas of American life for their belief that educa-tion can be enormously effective: the reduction of smok-ing, the rise in recycling, the reduction in drinking anddriving, the adoption of “safe sex.”

Some promote “social marketing” or education as akey to the eventual sustainability of our transportationsystem. They argue that Americans are bombarded withadvertising that, for economic reasons, encourages themto purchase larger and less fuel-efficient vehicles and touse them for more and more reasons (McGovern 2004).In contrast, in parts of Europe and Australia and mostrecently in experiments in American cities such as Port-land, Oregon (TravelSmart), willing households havehad their travel choices “audited” by trained outsiders.Household members were helped to reorganize theirweekly travel to take greater advantage of public tran-sit, form trip chains that reduce the number of automo-bile cold starts, combine the trips of household membersthat were previously made independently of oneanother, and forgo some trips entirely. Some see thistype of educational activity as promising for at least tworeasons. The first is the direct shift in travel behaviortoward sustainable mobility that they hope it will helpto bring about. The second is the fact that educationwill, perhaps more gradually, contribute to changes inpublic policy by making more aggressive approaches toregulation more acceptable in the political arena thanthey are now. Others, of course, think that well-mean-ing experiments in consumer education are likely toresult in little or no change in travel at the scale of ourentire society. Still others consider such an approach tobe completely misguided and doomed to fail, or worse,to interfere with individual freedom in a democraticsociety. Should we, as a group, conclude that wide-spread consumer education is one of the more promis-ing approaches to the attainment of sustainablemobility, or should we conclude that this view is wellmeaning but likely to be ineffective in the foreseeablefuture?

Regional Planning

In the United States regional transportation planning haslong emphasized the construction of transportationcapacity. As environmental, especially air quality, andsocial and economic impacts have become increasinglyimportant concerns in regional planning, our long-rangetransportation plans become more sophisticated, but theycontinue to emphasize capital investments in facilities.


In other parts of the world, however, the nature ofregional transportation plans is changing more funda-mentally. For example, regional long-range transporta-tion plans have been formulated that emphasize along-term commitment to sustainability as a first princi-ple in Sydney and Melbourne, Australia, and in a largenumber of European cities. Such plans go far beyondproposing new capital investments in corridors wheretraffic volume is likely to grow. Some of these plans pro-mote the redevelopment of older, formerly industrial ormilitary sites into high-density, mixed-use commercialand residential centers in proximity to public transitfacilities. Many have adopted approaches to regionalplanning intended to reduce the geographic expansionof metropolitan areas at their edges while promotinghigher densities at their cores. Some have set specific,and in a few cases ambitious, goals with regard tochanges in modal split or decreased rates of growth inautomobile travel and in the generation of GHGs. Oftenthese plans incorporate major capital investments intravel modes other than the automobile.

In a number of cases, emulated in a few notable plan-ning activities in the United States, the effort to developregional plans has identified threatened or sensitive nat-ural areas and then worked toward plans that wouldaccommodate forecast growth while protecting thoseenvironments. In other cases, planning models wereused, as they have rarely been in the United States, to“backcast” rather than to forecast. That is, certain envi-ronmental and travel goals were developed for the tar-get year of the plan, and the models were used to testalternative policies and consequently to select policiesthat would lead to the desired outcomes (Wachs 2000).

Should we, as a group, conclude that regional plan-ning is of potentially great value in achieving sustain-ability and recommend that the regional planningprocess be substantially overhauled in support of sus-tainability? The answer is not at all obvious. In the past,planners and policy makers have urged that regionalplans pay much more attention to transportation sys-tems management, travel demand management, mainte-nance and renewal of the existing capital plant, and thesystematic inclusion of telecommunications innovationsthrough a transition to intelligent transportation sys-tems. Despite such urgings and many revisions to plan-ning regulations included in the national highwayprogram, progress in reforming the regional transporta-tion planning process has been limited. We appear to beunable to achieve the dramatic institutional changes thatwould be needed to make regional planning more capa-ble of addressing sustainability. Some of us may arguethat a number of factors—the inertia in our existingplanning apparatus, the inevitability of some of ourpopulation and travel trends, and a reluctance toembrace aggressive regulation of the use of land and of

travel choices—make it far less cost-effective in the nearterm to embrace regional planning as a sustainabilitystrategy than to focus on technological change.

Conclusion

In this paper I have offered several questions that I hopecan help structure the discussion that is to follow in ourworkshops. The questions are summarized as follows:

• Can progress toward sustainability in transporta-tion be achieved in the United States primarily throughtechnological changes in vehicles, power trains, andfuels? Is it cost-effective to rely primarily on technolog-ical approaches?

• Can changes in statewide and metropolitan plan-ning contribute in a meaningful way to sustainability?Are changes needed in land use and urban form at theregional and neighborhood levels? Is basic planningreform feasible to the extent that regional planning cancontribute to sustainable mobility?

• Can American society, through education andmarketing, achieve a sufficient shift to more sustainablemodes of transportation, including walking, cycling,and public transit use, to warrant an increasing focus onsuch strategies in our approach to sustainability?

• Should pricing be used to a much greater extent tointernalize the externalities of transportation in order toapproach a more sustainable transportation system?

• Can American transportation policy adopt moredirect approaches to regulating travel choices andbehavior? If such approaches are adopted, can they pro-duce sufficient progress toward sustainable mobility tomake them worth the costs of undertaking?

Answers to these questions will be key to the sustain-ability debate that will characterize American trans-portation policy for many years to come. The questionsmay have answers applying in the short term differentfrom those applying in the longer run. At one level, theycan be answered rather superficially. It is, for example,possible to respond that the attainment of sustainablemobility will require progress simultaneously in all ofthe areas delineated by these questions. But it is not real-istic to think that society can forge ahead with equalvigor and with equal probability for success in all ofthese dimensions. At the other extreme, it is equally pos-sible to conclude that most progress made to date hasbeen the result of technological innovation and changeand that it is logical to presume that technologicalchange is the only promising path by which to approachsustainable mobility in America. In all likelihood, thesetwo extreme positions are both unsatisfactory. Selectingthe right mix of approaches is in the end a complex tech-


nical, political, and moral question. It requires that weconsider what is feasible given American political orga-nization and values, but it also requires us to balancewhat is internally feasible against what is likely to behappening in the rest of the world.

I doubt that we will be able to come up with finalanswers to these questions in the discussions that fol-low, and I expect that we will reconsider these questionsmany times over the coming decades. I hope that for-mulating the questions in these ways is a useful contri-bution to the debate that will follow in our workshopsand in many other forums to come.

ACKNOWLEDGMENTS

I benefited greatly from comments made on an earlierdraft of this paper by Jennifer Dill, Richard Gilbert,John Pucher, and Daniel Sperling. I owe several of theideas contained in this draft to their helpful suggestions.

REFERENCES

Banister, D., and J. Pucher. 2003. Can Sustainable TransportBe Made Acceptable? Presented at the 2nd SustainableTransport in Europe and Links and Liaisons withAmerica Focus Group Meeting on Institutions, Regula-tions, and Markets in Transportation, Santa Barbara,Calif., May 19–20.

Hakim, D. 2004. Much of Coastal U.S. May Follow Califor-nia on Car Emissions. New York Times, June 11, onlineedition.

Levine, J., A. Inam, and G.-W. Torng. 2005. A Choice-BasedRationale for Land Use and Transportation Alterna-tives: Evidence from Boston and Atlanta. Journal ofPlanning Education and Research, Vol. 24, No. 3, pp.317–330.

Lyons, W. M., S. Peterson, and K. Noerager. 2003. Green-house Gas Reduction Through State and Local Trans-portation Planning. Report DOT-VNTSC-RSPA-03-02.Volpe National Transportation Systems Center, Cam-bridge, Mass.

McGovern, E. 2004. Adopting Social Marketing Programs:Can They Help Us Decide to Leave the Car at Home?Manuscript submitted to Transportation.

Wachs, M. 2000. Refocusing Transportation Planning for the21st Century. In Conference Proceedings 20: Refocus-ing Transportation Planning for the 21st Century,Transportation Research Board, National ResearchCouncil, Washington, D.C., pp. 190–193.

Wachs, M. 2005. Then and Now: The Evolution of CongestionPricing in Transportation and Where We Stand Today. InConference Proceedings 34: International Perspectiveson Road Pricing, Transportation Research Board of theNational Academies, Washington, D.C., pp. 63–72.

World Business Council for Sustainable Development. 2004.Mobility 2030: Meeting the Challenges to Sustainability.www.wbcsd.org/web/publications/mobility/mobility-full.pdf.


5 3

Committee Member Biographical Information

David L. Greene, Chair, is Corporate Research Fellowat Oak Ridge National Laboratory. He has long beenregarded as a leader in sustainability as it pertains totransportation. He has spent 25 years in researchingtransportation energy and environmental policy issues.His research interests include analysis of policies to mit-igate greenhouse gas emissions from transportation, thedevelopment of theory and methods for measuring thesustainability of transportation systems, the modelingof energy demand, economic analysis of petroleumdependence, and the modeling of market responses toadvanced transportation technologies and alternativefuels. Dr. Greene has been active in the TransportationResearch Board (TRB) and the National ResearchCouncil for more than 25 years and has served on sev-eral standing and ad hoc committees dealing withenergy and environmental issues and research needs. Heis past chair and an emeritus member of TRB’s EnergyCommittee, past chair of the Section on Environmentaland Energy Concerns, and a recipient of the TRB PykeJohnson Award. Dr. Greene is a lifetime National Asso-ciate of the National Academies. He was a U.S. partici-pant in the second and third assessments of theIntergovernmental Panel on Climate Change as a leadand contributing author.

Dr. Greene received a B.A. from Columbia Univer-sity, an M.A. from the University of Oregon, and aPh.D. in geography and environmental engineeringfrom the Johns Hopkins University. After joining OakRidge National Laboratory, he founded the Transporta-tion Energy Group and later established the Transporta-tion Research Section. He has published more than 150

articles in professional journals, contributed to booksand technical reports, and authored or edited threebooks (Transportation and Energy, Transportation andGlobal Climate Change, and The Full Costs and Bene-fits of Transportation). He served as the first editor-in-chief of the Joumal of Transportation and Statistics andcurrently serves on a number of editorial boards, includ-ing that of Energy Policy.

William R. Black is Professor of Geography and Publicand Environmental Affairs at Indiana University. Afterreceiving his doctorate from the University of Iowa, hejoined the faculty of the Department of Geography atIndiana University. He also taught at Miami Universityof Ohio and Purdue University. At Indiana University heserved as Director of the Center for Urban and RegionalAnalysis, Chairman of the Urban and Regional AnalysisFaculty, Chairman of the Department of Geography,and Acting Director of the Transportation ResearchCenter. He is currently serving a second term as Chair-man of the Department of Geography. He directed railplanning for the state of Indiana during the rail restruc-turing in the Midwest and Northeast United States inthe 1970s. Subsequently, he served as a member of thePhiladelphia-based activation task force that created theConsolidated Rail Corporation (better known as Con-rail) in 1976. He served as the first Director of the Indi-ana Department of Transportation in 1980.

Dr. Black has been a transport adviser to the state ofIndiana for the past 30 years, and he is the recipient ofa Sagamore of the Wabash Award from that state for hispublic service. He has been a member of TRB for more

than 30 years. He served for 6 years as Chairman of theTRB Social and Economic Factors of TransportationCommittee. He continues as a member of that commit-tee, the International Activities Committee, and theTask Force on Sustainable Transportation. He servedtwo terms as Chairman of the Transport ResearchGroup of the Association of American Geographers(AAG) and is the 1995 recipient of that group’s EdwardL. Ullman Award for contributions to transport geogra-phy. He presented the Fleming Transportation Lectureat the 2000 meeting of AAG. From 1995 to 1998 hewas North American Associate Editor of the Journal ofTransport Geography.

Dr. Black continues to serve on the journal’s editorialboard as well as the boards of two international environ-mental journals. He is currently Coordinator of STAR, aNational Science Foundation thematic research networkon sustainable transport, and North American Coordina-tor of STELLA, a thematic research network on sustain-able transport of the European Commission. He hasdirected 20 research projects for state and federal trans-port agencies. He is the author or coauthor of five booksand the principal author of more than 150 researchpapers and reports. His current research interests are inthe areas of sustainable transportation, indicators of sus-tainability, environmental impacts of transport, state andregional flow modeling, the use of network autocorrela-tion analysis for examining motor vehicle accidents, andfull-cost analysis of alternative modes.

David G. Burwell is a Senior Fellow in the Prague Insti-tute of Global Urban Development, a Washington thinktank, where he is an observer of transportation and envi-ronmental policy. He was President and CEO of the Sur-face Transportation Policy Project (STPP), a nationwidenetwork of more than 250 organizations devoted toimproving the nation’s transportation system. He directedSTPP’s New Directions Initiative, a multiyear campaignthat makes federal and state transportation policies betterserve families and communities. Mr. Burwell cofoundedSTPP and served as its chair from 1990 to 1997.

Mr. Burwell was cofounder of the Rails-to-TrailsConservancy, a nonprofit organization devoted to theconversion of abandoned rail corridors to public trailuse, and served as its president for 15 years. Mr. Burwellworked as legal counsel for the National Wildlife Feder-ation, where he specialized in transportation, land use,and air quality issues. He has authored several booksand articles on transportation law and policy. He wasthe initial recipient of the Transportation AchievementAward, an annual STPP award for outstanding achieve-ment in transportation policies.

Thomas M. Downs was appointed President and CEOof the Eno Transportation Foundation in 2003. He has

worked most of his life in transportation or general gov-ernment. In a career that spans more than 30 years, hehas served in general government as a city manager inthe Midwest, as a White House Fellow, and as CityAdministrator of Washington, D.C. In transportationhe has served as an Executive Assistant to the U.S. Sec-retary of Transportation, as Associate Administrator ofthe Federal Highway Administration (FHWA) for Plan-ning and Budget, as Executive Director of the FederalTransit Administration, and as Director of the Washing-ton, D.C., Department of Transportation. He has servedas Chair of the Washington Transportation PlanningBoard, the metropolitan planning organization for theWashington metropolitan area.

Dr. Downs left the Washington area in 1988 tobecome the President of the Triborough Bridge and Tun-nel Authority in New York City. He later served as theCommissioner of Transportation for the State of NewJersey. In that role he also served as Chairman of theNew Jersey Transit Corporation. During this time healso served as Chairman of the Northeast Association ofState Transportation Officials and as a member of theExecutive Committee of the American Association ofState Highway and Transportation Officials. He hasalso served as a member of the Executive Committee ofTRB and on numerous advisory committees at TRB andthe U.S. Department of Transportation. He was one ofthe founders of the I-95 Corridor Coalition and theregional E-ZPass coalition in New York.

In 1993 Dr. Downs was appointed Chairman andCEO of Amtrak, the nation’s passenger railroad. Hesubstantially completed the electrification of the North-east Corridor and completed the purchase of high-speedtrain sets. He helped Congress create a $2.4 billion trustfund for the railroad. After leaving Amtrak, he becamethe CEO of the National Association of Home Builders(NAHB). He left NAHB to join the faculty of the Uni-versity of Maryland, where he served as Professor andDirector of the National Center for Smart Growth.

He is a Fellow of the National Academy of PublicAdministration and is the author of numerous articlesand monographs. He has advanced degrees from theUniversity of Missouri and the University of Kansas.

Richard Gilbert is an urban issues consultant whofocuses on transportation, waste management, energysystems, and urban governance, with clients in NorthAmerica, Europe, and Asia. He serves as transport con-sultant to the Paris-based Organisation for EconomicCo-operation and Development (OECD) and to CivicExchange, a Hong Kong–based think tank; as part-timeresearch director of the Toronto-based Centre for Sus-tainable Transportation (CST); and as adjunct profes-sor in the University of Sherbrooke’s Faculty ofAdministration.


Dr. Gilbert received a Ph.D. in 1966 in experimentalpsychology and in an earlier career was a psychologyprofessor and researcher. He taught at universities in the1960s and 1970s in Ireland, Scotland, the United States,Mexico, and Canada and was associated with theAddiction Research Foundation of Ontario from 1968to 1991. In the 1990s he taught graduate courses inplanning and urban governance at York University’sFaculty of Environmental Studies.

He served as a member of the councils of the City ofToronto and Metropolitan Toronto from 1976 to 1991and as president of the Federation of Canadian Munici-palities from 1986 to 1987. On retiring as a municipalpolitician, he became the first president and CEO of theCanadian Urban Institute, a position he held from 1991to 1993, and has worked as an independent consultantsince then.

Major reports published during the past 2 yearsinclude Electrifying Hong Kong: Making Transport Sus-tainable for Civic Exchange; Soft Measures and Trans-port Behaviour for Umweltbundesamt, the GermanFederal Environment Agency, and OECD; Energy andSmart Growth for the Neptis Foundation and the gov-ernment of Ontario; Policy Instruments for AchievingEnvironmentally Sustainable Transport for OECD; andSustainable Transportation Performance Indicators forCST (supported by four departments of the governmentof Canada).

Kevin E. Heanue consults on transportation planning,environmental analysis, organizational development, andrelated issues. He began his consulting practice after a 40-year career with FHWA. Clients have included TRB, theEno Transportation Foundation, Cambridge Systematics,the Northern Virginia Planning District Commission, theAmerican Highway Users Alliance, OECD, the CivilEngineering Research Foundation, and FHWA. Mr.Heanue has consulted on topics including induced travel,a bridge feasibility study, transportation research priori-ties, international freight movement, intermodal trans-portation, and the role of metropolitan planningorganizations in planning for freight movements.

In his most recent assignment with FHWA, Mr.Heanue served for 8 years as Director of the Office ofEnvironment. During this time he administered thestatewide, intermodal, and urban planning programs ofthe agency, as well as the environmental programs andrequirements relating to the National EnvironmentalPolicy Act, the Clean Air Acts, and the Clean WaterActs. In addition, he had a major role in the develop-ment and implementation of the Intermodal SurfaceTransportation Efficiency Act and in the developmentof the Transportation Equity Act for the 21st Century.

Mr. Heanue is active in TRB. He has served on numer-ous committees, research panels, and conference steering

committees and on the Group 1 Council. He is foundingchair of the Task Force on Transportation and Sustain-ability. He is a Fellow of the American Society of CivilEngineers and serves on the membership advisory reviewcommittee. He has been a member of the Road Gangsince 1984 and was its chairman in 1998. He has been amember of Lambda Alpha, an international honoraryland economics society, since 1990. He is a registeredProfessional Engineer in the District of Columbia.

Mr. Heanue recently served on the InternationalSteering Group for the World Bank. He directed theDublin, Ireland, Transportation Study from 1970 to1971; in 1986 he served as a consultant to the WorldBank in China. Mr. Heanue has traveled extensively onFHWA missions to Mexico, England, France, and Ger-many. Between 1989 and 1995, he represented theUnited States as a member of the Permanent Interna-tional Association of Road Congresses Committee onUrban Roads. He served as the U.S. representative onthe Asia-Pacific Economic Cooperation Urban Trans-port Forum from 1996 to 1998.

Mr. Heanue is the coauthor of a recently publishedtextbook, Road Ecology: Science and Solutions. Hereceived his B.S. in civil engineering from Tufts Univer-sity (cum laude) and his M.S. in civil engineering fromGeorgia Institute of Technology.

Marianne Millar Mintz is Transportation Systems Engi-neer at Argonne National Laboratory. She has workedwith several offices of the U.S. Department of Energyand with the Federal Emergency Management Agency.She is focused on evaluating opportunities and investi-gating the impacts associated with the deployment ofadvanced engine and fuel technologies into the light-and heavy-duty vehicle fleet, expanding and recalibrat-ing transportation energy forecasting and impact assess-ment models, and developing methods to identifymarket segments and estimate the likely penetration ofalternative- and flexibly fueled vehicles into the U.S.transportation fleet. She is Chair of TRB’s Transporta-tion Energy Committee. Ms. Mintz received a B.A. fromthe University of California and an M.A. from LoyolaUniversity, Los Angeles.

Arthur (Chris) Nelson is Professor and Founding Direc-tor of Graduate Studies in Urban Affairs and Planningat Virginia Polytechnic Institute and State University’sAlexandria Center. Before this appointment, he servedfor 15 years as Professor of City and Regional Planningin the College of Architecture at Georgia Tech, where hewas also appointed to the faculties in public policy andinternational affairs in the Ivan Allen College. In addi-tion, he served in the Transportation Research and Edu-cation Center in the College of Engineering. He was anAdjunct Professor of Law at Georgia State University.

5 5COMMITTEE MEMBER BIOGRAPHICAL INFORMATION

Dr. Nelson is recognized broadly for his work onthe relationship between metropolitan developmentpatterns and economic development, use and depen-dency on alternative transportation modes, and socialequity. His work in metropolitan governance hasshown the benefits of federal-style governance systemsin managing growth and investment at the metropoli-tan scale. That has led to current work on the rela-tionship between metropolitan planning organizationvoting structure and transit investment, with implica-tions for long-term metropolitan economic develop-ment, social justice, and fiscal stability. Dr. Nelson isone of the world’s leading experts on impact fees, espe-cially transportation impact fees, and he has pioneeredmethods of calibrating impact fees to account forsocial and economic equity, location efficiency, andeconomic development.

Over the past two decades, Dr. Nelson’s work hasbeen supported by such organizations as the NationalScience Foundation; TRB; the Federal Transit Adminis-tration and other federal agencies; the Brookings Insti-tution; the Lincoln Institute of Land Policy; theAmerican Planning Association; numerous foundations;and local, regional, and state agencies. He has morethan 150 publications to his credit. Dr. Nelson’s stu-dents have won numerous national awards in planning,policy, and design, and he has won awards as teacher ofthe year, professional educator of the year, andresearcher of the year.

John P. Poorman has 30 years of experience in trans-portation planning with the Capital District Trans-portation Committee (CDTC), where he has been StaffDirector since 1981. CDTC is the designated metropol-itan planning organization for the four counties con-taining the Albany and Saratoga Springs, New York,urbanized areas. CDTC was selected by the Associationof Metropolitan Planning Organizations for its 1997National Award for Outstanding Achievement and wasselected as the 1997 Employer of the Year by theWomen’s Transportation Seminar of New York’s Capi-tal District.

Mr. Poorman has been Chairman of the New YorkState Metropolitan Planning Organizations (NYSMPOs)since 1995. NYSMPOs was selected by the Associationof Metropolitan Planning Organizations for the 2000National Award for Outstanding Achievement in SpecialProjects for its statewide shared-cost initiatives. He wasa member of the Board of Directors from 1995 to 1998and was Vice Chairman from 1996 to 1997.

Mr. Poorman has been an adjunct faculty member inthe State University of New York at Albany’s graduateUrban and Regional Planning Program, a member ofthe Board of Advisors of the Eno Transportation Foun-dation, a member of TRB’s Executive Committee, and a

member of the National Research Council’s SurfaceTransportation Environmental Cooperative ResearchProgram Advisory Board.

He is the recipient of a 1996 Environmental Fellow-ship from the German Marshall Fund of the United Statesto study European approaches to full-cost accounting oftransportation impacts. From 1991 to 1992 he was Direc-tor of the Urban Planning Section of the New York StateDepartment of Transportation (NYSDOT) as part of anexecutive exchange between CDTC and NYSDOT. In1988 he was honored by NYSDOT, and in 1989 honoredby New York State County Highway Superintendents. In2003 Mr. Poorman was named “Ally of the Year” by ARegional Enterprise to Support Empowerment, Albany.

Mr. Poorman has a bachelor of arts in economicsfrom Haverford College and a master of science intransportation from Northwestern University.

Daniel Sperling is Professor of Civil Engineering andEnvironmental Science and Policy and is foundingDirector of the Institute of Transportation Studies (ITS-Davis) at the University of California, Davis. He is alsocodirector of the Fuel Cell Vehicle Center and HydrogenPathways research program at the University of Califor-nia, Davis. ITS-Davis specializes in advanced trans-portation technologies, energy and environmentalimpacts, and travel behavior. It was selected as a finalistfor the 2003 World Technology Energy Award.

Dr. Sperling is recognized as a leading internationalexpert on transportation, energy, and environmentalpolicy, particularly with respect to advanced vehicletechnology and alternative fuels. In the past 20 years, hehas authored or coauthored more than 160 technicalpapers and eight books.

Dr. Sperling is Associate Editor of TransportationResearch D (Environment) and is a current or recent edi-torial board member of five other scholarly journals. Heis a recent member of 10 National Academies commit-tees, including Hydrogen Production and Use, HighwayFinance, Biomass Fuels Research and Development, andTransportation and a Sustainable Environment.

He is founding chair and emeritus member of theAlternative Transportation Fuels Committee of TRBand serves on many advisory committees and boards ofdirectors for environmentally oriented organizations.He consults for international automotive and energycompanies, major environmental groups, and severalnational governments.

Dr. Sperling has testified numerous times to Con-gress. He has provided advice to various governmentagencies and has provided keynote presentations andinvited talks in recent years at international conferencesin Asia, Europe, and North America.

Dr. Sperling was nominated for the 2003 World Tech-nology Energy Award (individual). He was awarded the


2002 Carl Moyer Memorial Award for Scientific Lead-ership and Technical Excellence by the Coalition forClean Air; the 1998 Employer of the Year Award by theWomen’s Transportation Seminar of Sacramento; the1997 Clean Air Award by the American Lung Associa-tion of Sacramento; the 1996 Distinguished Public Ser-vice Award by the University of California, Davis; andthe 1993 Gilbert F. White Fellowship by Resources forthe Future, Washington, D.C.

Before obtaining his Ph.D. in transportation engi-neering from the University of California, Berkeley(with minors in economics and energy and resources),Dr. Sperling worked 2 years as an environmental plan-ner for the U.S. Environmental Protection Agency and 2years as an urban planner in the Peace Corps in Hon-duras. He earned an undergraduate degree in engineer-ing and urban planning from Cornell University.

5 7COMMITTEE MEMBER BIOGRAPHICAL INFORMATION

5 8

Participants

William Anderson, Center for Transportation Studies,Boston University, Massachusetts

Michael Ball, Transport Canada, Ottawa, OntarioJohn Bartle, University of Nebraska, OmahaWilliam Black, Indiana University, BloomingtonPaul Brooks, St. Lawrence Cement, Albany, New YorkDavid Burwell, Project for Public Spaces, Bethesda,

Maryland Sarah Campbell, TransManagement, Inc., Washington,

D.C.Anne Canby, Surface Transportation Policy Project,

Washington, D.C.Christina Casgar, Office of Intermodalism, U.S.

Department of Transportation, Washington, D.C. Michael Cummings, Pew Center on Global Climate

Change, Arlington, VirginiaLewis Dale, General Motors, Detroit, MichiganElizabeth Deakin, University of California

Transportation Center, BerkeleyThomas Deen, Consultant, Stevensville, MarylandKarin DeMoors, TransTech Management, Inc.,

Washington, D.C.Greg Dierkers, Center for Clean Air Policy,

Washington, D.C.Jennifer Dill, Portland State UniversityThomas Downs, Eno Transportation Foundation,

Washington, D.C.James Dunn, Political Science Department, Rutgers

University, Camden, New JerseySharon Feigon, I-GO Carsharing, Center for

Neighborhood Technology, Chicago, Illinois

Wendell Fletcher, Bureau of Transportation Statistics,Washington, D.C.

Emil Frankel, U.S. Department of Transportation,Washington, D.C.

David Gardiner, BBG Group, Arlington, VirginiaRichard Gilbert, Centre for Sustainable

Transportation, Toronto, Ontario, CanadaGenevieve Giuliano, School of Policy, Planning, and

Development, University of Southern CaliforniaThomas Gladwin, University of MichiganDavid Greene, National Transportation Research

Center, Oak Ridge National Laboratory, Knoxville,Tennessee

Kevin Heanue, Consultant, Alexandria, VirginiaJohn Horsley, American Association of State Highway

and Transportation Officials, Washington, D.C.Ileana Ivanciu, Dewberry, Parsippany, New JerseyAshby Johnson, Houston–Galveston Area Council,

TexasBob Johnston, University of California, DavisHal Kassoff, Parsons Brinckerhoff, Washington, D.C.David Kriger, iTRANS Consulting, Inc., Ottawa,

Ontario, CanadaReinhart Kuehne, Institute of Transportation Research,

Berlin, GermanyMichael Lawrence, Jack Faucett Associates, Bethesda,

MarylandLinda Lawson, Office of Safety, Energy, and Environment,

U.S. Department of Transportation, Washington, D.C.Martin Lee-Gosselin, Laval University, Quebec,

Canada

Lewison Lem, AAA, San Francisco, CaliforniaSteve Lockwood, PB Consult, Rockville, MarylandMichael MacCracken, Climate Institute, Bethesda,

MarylandPaul Marx, Federal Transit Administration,

Washington, D.C.Jim McKenzie, Metroplan, Little Rock, ArkansasMarianne Millar Mintz, Argonne National Laboratory,

Argonne, IllinoisCamille Mittelholtz, U.S. Department of

Transportation, Washington, D.C.Arthur Nelson, Virginia Polytechnic Institute and State

University, AlexandriaJoan Ogden, Institute of Transportation Studies,

University of California, DavisAnthony Perl, Department of Political Science,

University of Calgary, Calgary, Alberta, CanadaSteven Plotkin, Argonne National Laboratory,

Washington, D.C.John Poorman, Capital District Transportation

Committee, Albany, New YorkJohn Pucher, Rutgers UniversityMichael Replogle, Environmental Defense,

Washington, D.C.Elizabeth Riklin, Office of Policy, U.S. Department of

Transportation, Washington, D.C.Jonathan Rubin, University of MaineMike Savonis, Federal Highway Administration,

Washington, D.C.

Lee Schipper, EMBARQ/World Resources Institute,Washington, D.C.

Rolf Schmitt, Office of Freight, Federal HighwayAdministration, Washington, D.C.

Gloria Shepherd, Federal Highway Administration,Washington, D.C.

James Shrouds, Office of Natural and Human Environment, Federal Highway Administration,Washington, D.C.

Carl Simon, Center for the Study of Complex Systems,University of Michigan

Daniel Sperling, Institute of Transportation Studies,University of California, Davis

John Sullivan, Ford Motor Company, Ann Arbor,Michigan

Joseph Szyliowicz, University of DenverG. Alexander Taft, Missoula, MontanaKurt Van Dender, Department of Economics,

University of California, IrvineMartin Wachs, Institute of Transportation Studies,

University of California, BerkeleyMichael Wang, Argonne National Laboratory,

Argonne, IllinoisDong Yan, Institute of Comprehensive Transportation

of National Development and Reform Commission,Beijing, China

5 9PARTICIPANTS

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