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33 This appendix provides a more detailed overview of the case studies performed under the direction of Dr. Elizabeth Deakin and Karen Trapenberg Frick of the University of Cali- fornia Transportation Research Center.50 The four technology applications treated in case studies included â¢ ITS, â¢ Pavement technology and infrastructure, â¢ Context-sensitive design, and â¢ Integrated transportation-land use modeling. Case Studies of Technology Adoption in Transportation Table A-1 provides an overview of the interviews conducted for these case studies. Interviewees included representatives of state DOTs, MPOs, industry, local and federal government, and leading faculty experts across the United States. ITS ITS refers to an array of technologies with potential to con- tribute to many areas of transportation: planning and fore- casting, design, construction, service delivery, operations and management, and marketing. In broad terms, ITS encompasses information and communication technology applications that could improve transport safety, security, reliability, environ- mental performance, and customer convenience. Examples of ITS applications include advanced traffic signal systems, elec- tronic pricing devices, real-time transit information, vehicle performance monitoring devices, location information sys- tems, and automated driving technologies. Researchers at the University of California previously con- ducted a detailed literature review and extensive interviews to assess factors affecting ITS implementation as a âmainstreamâ transportation planning activity (Deakin, 2006.) This work builds on and updates that study. The study of ITS barriers focused particularly on the many non-technical barriers: â¢ Difficulty assessing the performance of ITS applications, â¢ Lack of market pull and of motivating studies, â¢ Lack of market assessment and implementation planning efforts, â¢ Insufficient staff or inadequate skill-mix, â¢ Difficulty establishing intra- and interagency partnerships, â¢ Difficulty keeping pace with technological advancements, and â¢ Lack of funding. Asked to identify the top barriers to faster and more wide- spread implementation of ITS technologies, interviewees widely agreed on several recurring factors. One of the key concerns revealed in an earlier study of ITS barriers (Deakin et al., 2006) was that proponents of ITS often had unrealistic expectations of system performance or impact and benefits were overstated. Interviewees from this study noted that agencies had taken a more realistic view of ITS in recent years. Concerns remain, however, about how the costs and ben- efits of ITS are evaluated and by whom. Several interviewees noted that ITS cost-benefit analyses and evaluations are often done by the same individuals who developed or implemented the technology, either at the agency or at supporting firms, suggesting there may be a lack of objectivity in assessing the costs and benefits. Additionally, much of the success of ITS depends on the market environment, public perception, an agencyâs human capital resources, and other non-technical factors. Elected A p p e n d i x A Technology Assessment, Adoption, and Implementation by Transportation Agencies 50 The studies have not been formally published at the time of this writing. Details may be obtained by contacting the University of California, Berkeley researchers directly.
34 officials commented that there was not much evidence of a constituency for the changes [in practice towards imple- menting ITS], and while they were willing to help create one if there were clear benefits to the public or important user groups, the technology advocates often do not make it clear how an individual, or an industry such as trucking [for tech- nologies like, roadway sensors and on-board information systems] would benefit from the changes being proposed. A lack of market pull exacerbates these challenges. One inter- viewee commented, âThe public isnât asking for most of this stuff, so decisionmakers see it as optional and in the current economic climate, it wonât get funded.â One MPO staff member noted that, at one point, the state and local agencies that the MPO worked with had hopes of selling their traffic and transit data derived from sensors, GPS, and so forth. Now, the data are posted on line and made available for free for direct consumer use or development of third-party applications. In her view, this approach has greatly accelerated implementation of ITS information systems, though she added that it was âa bit humblingâ for agencies to have to accept that their data did not have much value in the marketplace. One possibility raised in several of the interviews was that implementation of smart highway technologies could be accel- erated if there were more markets for the data and noted that one possible internal and external market is for regional and statewide planning. Collecting traffic volume and speed data is easy with currently available ITS technologies, and collecting origin-destination data is also feasible and has been demon- strated in several projects. However, current implementations often fall short of providing the data that planners would need. Decisionmakers in public agencies also expressed a certain degree of frustration with their technical advisors, reporting that they sometimes have difficulty understanding proposals because the technical staff uses jargon and abbreviations to discuss their proposals. Despite the importance of market assessment and imple- mentation planning, much ITS work continues to focus on technology development. In some instances, research has been directed to broader questions of costs and benefits in the context of existing and emerging markets, organizational capacities, and institutional relationships. However, interview- ees raised additional concerns about this work, noting that it is often undertaken by engineers and technologists, rather than social scientists. Interviewees suggested methodologi- cal and other shortcomings in their cost-benefit analyses in these areas. As one consultant noted, âThe technology developers are advocates, but not necessarily effective ones, because they are not expert in market assessments, strategic positioning, and other factors that, in addition to technology itself, are needed for success.â There was near-unanimous agreement that many DOTs were having difficulty with ITS implementation, for several reasons. Partnerships are needed to implement and partner- ships necessitate a change in agency culture, including less hierarchical decision-making. In the expertsâ view, separate ITS units and ITS implementation plansâan approach taken by several agenciesâcan foster strategic thinking about ITS technology development but may hinder ITS incorpora- tion into ongoing plans, programs, and funding streams. As noted earlier, there was near-unanimous agreement that ITS deployment requires coordination between agencies and with developers and other groups. Stronger partnerships with local government and other state agencies developing mutually beneficial and multi-purpose applications were recommended. Interviews by topic: Federal Agency State Agency MPO City, County, Special Dist. Elected Officials Consultants, Private Sector University Researcher Totals ITS 7 5 5 6 5 3 6 37 CSS 8 5 5 8 6 2 6 40 Models 6 5 6 8 5 5 6 41 Pavement 2 8 1 3 0 3 4 21 Totals by organizaÂon type 23 23 17 25 16 13 22 139 Interview locaÂons DC, CA, MA CA, FL, MA, WI CA, FL, TX CA, FL, TX, MA, MD, NY, OH, VA, WA, WI CA, DC, FL, MA, NH, NY CA, DC, MA, NY, WA, TX CA, FL, GA, MA, MN, OR, TX Note: Some interviews covered more than one topic Table A-1. Case study interviews by organizational type, topic, and location.
35 The need for staff with new skills was identified as a bar- rier, if agencies chose to proceed independently rather than contracting for services. In particular, many ITS technologies require extensive knowledge of computer science and elec- trical engineering sensor technologyâdisciplinary expertise not currently common in transportation agencies. Conflicting objectives sometimes get in the way of ITS applications. For example, transportation agency staff noted consumer and provider interest in cell phone apps that would notify drivers of fog, stopped traffic ahead, parking availabil- ity at their destination, and more. But concerns about dis- tracted driving are deterring publicly supported applications. Making data available on websites for independent product development rather than providing the apps directly has been an increasingly common response. Standards pose impediments to adopting ITS because they cannot keep up with the pace of technology development and become restrictive. As one interviewee noted, âStandards are designed to provide for consistent products with a known per- formance, and donât leave any room for the nonstandard, even if itâs better.â Relatedly, slow business processes were another issue raised by several, who commented that by the time a pur- chase order wended its way through their purchasing depart- ment or a contract was negotiated and signed, it was often necessary to revise the details because the technology had changed or the services being sought were no longer available. One interviewee noted, âIf technology is changing every three months, it doesnât work to have contracts or procurement processes that take six months.â Some further argued that the private sector should be left to implement ITS applications such as traveler information systems, because the technolo- gies for providing it were changing too rapidly for government agencies to be able to take the lead. Respondents urged that future ITS work should pay more attention to legal and institutional issues and provide a clearer sense of ânext steps.â A demonstrationâproof of conceptâ may be successfully implemented but what to do next remains unclear. ITS deployment is further hampered because many systems are not yet ready for low-risk implementation and there is reluctance in public agencies to experiment with unproven technologies using public funds. Agencies also face financial constraints in implementing ITS. Efforts have been made to continue the deployment of ITS, but the reduction of earmarked federal and state funds for ITS projects was identified by many agency staff members as limiting implementation. âWhen funds [restricted to use for ITS] were available, the research team could add at least some technology to projects. Without those funds, ITS looks like an optional extra, and it is first to be cut when project costs are high,â one state DOT official put it. At the same time, senior managers noted that ITS was being introduced and improved as opportunities presented them- selves. âNew buses are equipped with GPS, new traffic signals are âsmart,â new traffic management information systems connect to regional public information centers and cell phone apps,â pointed out one manager, a viewpoint echoed by many. âWe are implementing ITS when we replace equipment. We cannot afford to do it any other way,â said another. Transit agency staff members echoed the ideas that ITS technologies were being implemented as equipment was being replaced, that funding limitations meant that service- enhancing technologies took a lower priority than maintain- ing existing services, and that private-sector initiatives with agency cooperation were likely the better strategy for many agencies than the reverse. CSSs CSS refers to an innovation in transportation system design and process that combines street design, multimodal opera- tions, landscaping, and streetscape investments, coordinated with land uses along the street being remedied. AASHTO and FHWA offer the following definition: Context-sensitive solutions (CSS) is a collaborative, interdis- ciplinary approach that involves all stakeholders in providing a transportation facility that fits its setting. It is an approach that leads to preserving and enhancing scenic, aesthetic, historic, community, and environmental resources, while improving or maintaining safety, mobility, and infrastructure conditions (AASHTO/FHWA, 2007). CSS evolved over several decades as ideas drawn from expe- riences with traffic-calming, traffic mitigation, and promotion of transit non-motorized modal concepts were integrated. CSS is in part a reaction to frustrations over stringent design standards. Before ISTEA, roads paid for with federal funds were required to meet guidelines set forth in the AASHTO âGreen Bookâ or obtain design exceptions from the FHWA, a process many viewed as arduous, time consuming, and somewhat arbi- trary. Many states had similar design regulations and similar mandates for compliance unless a design exception request was granted. Design standards were intended to create safe, efficient facilities, and transportation engineers were trained to design by the book to ensure compliance with the standards. Yet many other transportation engineers, along with landscape architects and urban planners, chafed at the âone size fits allâ character of the design rules, which for the most part paid little attention to context. They argued that well-trained pro- fessionals could assess the safety and suitability of designs and produce better products that were more in keeping with their surroundings. Yet litigation when designs veered from the guidebooks reinforced many transportation engineersâ concerns about seeking design exceptions.
36 Responding to the urgings of the critics, Congress added provisions to ISTEA, signed into law in 1991, that gave states the option to adopt alternative design, safety and construc- tion standards for roads not on the designated National Highway System. The National Highway System Act of 1995 extended the option of alternative design standards to NHS highways other than Interstate highways. Responding to these new authorizations, the FHWA issued guidance for CSS in 1997. Several additional design manuals and guidance docu- ments on best practices in CSS followed. Interviewees noted that a handful of states and cities are widely regarded as leaders in implementing CSS, but individ- ual examples of good context-sensitive design can be found all over the United States. However, many U.S. practitioners (and several of those interviewed specifically for this study) find that a focus on CSS remains an exception rather than a rule. In their view, many areas have adopted policies allowing design exceptions to proceed somewhat more readily than in the past, but the designs are still exceptions. Some also think that good design remains elusive and few areas have been able to implement CSS successfully as a general policy (examples are for specific links or small stretches, not for the overall planning and design practice). The researchers interviewed both supporters and skeptics of CSS to understand the reasons for the uneven adoption of CSS. Interviews revealed several barriers: â¢ Controversial and confusing policies and standards, â¢ Lack of persuasive performance assessment, â¢ Conflicting mission goals, â¢ Agency culture and inertia, â¢ Interagency disagreements, â¢ Insufficient leadership, and â¢ Conflict with local public interests. Interviewees largely agreed that part of the problem CSS proposals face is that CSS policy has, for the most part, been an additional layer rather than a revision: previous policies and design standards are still in place. However, supporters and skeptics offered different interpretations of this conclu- sion. For CSS supporters, the layering of policiesârather than revisionâindicates a failure to change organizational culture and practices to reflect a new and more progressive approach to street design. They believe this undermines the intent of the policy to reduce the need for design exceptions. They further believe the policy should have led to a broad rebalanc- ing of the weight given to mobility versus access as a function of context. CSS skeptics, however, see a narrow interpretation of CSS policies as appropriate. In their view, ânormalâ stan- dards are best practice and CSS policies accommodate special circumstances under which exceptions to design standards might be allowed, together with an explication of how such acceptable design exceptions might be produced. CSS proponents and opponents seemed to have conflict- ing mission goals and priorities and to interpret performance assessments of projects differently. For example, CSS propo- nents believed that lane widths could be safely reduced, that narrowing road width would in general improve safety, that parking spaces could be designed for the average vehicle rather than the largest, and that bike lanes could be fit in by reducing travel lanes. Skeptics worried that these changes would lead to more delays, more conflicts, and more crashes, and saw lane nar- rowing as an action to be taken only when there was no other choice. CSS proponents also argued that level of service stan- dards should be relaxed or transformed into multimodal per- formance measures in urban areas. For the skeptics, the likely resultsâincreases in motor vehicle delay and congestionâ were viewed as unacceptable. The researchers found these sharply differing viewpoints within and between departments in the same agency and between state and local governments. The researchers also found cultural differences within agen- cies as well as inertia. Younger staff members are more likely to be comfortable with CSS than their older counterparts. One senior staff member at a state DOT commented that CSS policies âwere certainly not consistent with [his] many years of educa- tion and practice.â Another commented that CSS policy seemed to him to be a âfadâ that had caught the attention of a previ- ous executive; he added, â[Executives] come and go.â This staff member saw CSS as something that had dubious value overall, because in his view, with the street redesigns that CSS espouses for urban areas, traffic delays would be certain but increases in biking, walking, and transit use were likely to be modest at best. Another senior engineer commented that the CSS guidelines were optional and their application needed to be limited to cases where they could be applied using excess capacity. In contrast, younger engineers had been introduced to traffic-calming in undergraduate or graduate classes. They were sympathetic to the idea that land use needed to be con- sidered in selecting street designs and traffic controls; thought it was their responsibility to create good opportunities for walking, biking and transit; and believed that environmen- tal considerations and the preferences of local residents and businesses needed to be weighed heavily in developing a street design and traffic operations plan. In this regard, the views of the younger generation of traffic engineers were much more closely aligned with those of the planners and landscape architects interviewed, who were almost unanimous in their support for CSS. These differences also contributed to interagency conflict. City staff trying to manage multi-use arterials, especially ones that pass through residential areas or shopping districts, were frustrated with what they saw as foot-dragging by opponents to the CSS policy. In one case, city planners had redesigned a
37 major bus route and shopping street to be more multimodal and community-oriented. The state DOT was reluctant to issue the design exception because it feared that the level of service on the street would significantly worsen. The city developed a detailed traffic micro-simulation model to confirm the find- ings of the simpler modeling, which showed that traffic could be accommodated with little additional delay. One of the city transportation executives noted, âSmaller or less affluent cities would not be able to do this and would probably have given up.â One elected official saw interdepartmental and interagency conflicts as a failure of leadership, arguing that top execu- tives in these agencies âshould clarify expectations, insist on change, reward successes, and see the new policy imple- mented throughout organization, ânot just added as a new requirement on top of the older ones.â Other researchers commented that it is not always recalci- trant public agency staff members who oppose CSS; some- times it is motorists and merchants who believe their success depends on easy motor vehicle access. Several agency staffers shared problems they had faced when angry residents, workers, and merchants found out about a street redesign project only after its implementation was underwayâdespite strong and continuous outreach efforts, including design charrettes, pub- lic information meetings, and information packets sent to all local addresses. While the staff acknowledged that this problem was not unique to CSS but was encountered in many planning projects, they noted that traffic management issues are often among the most contested in their cities, and CSS had been a lightning rod for controversy in several states and cities. Advanced Transportation and Land Use Models 51 Travel demand modeling is a core tool of transportation planning. Travel demand models were first developed in the 1940s and 1950s as a new technology for metropolitan trans- portation planning. The models were used to study patterns of demand for travel in cities and metropolitan regions and to estimate the resulting demand for highways and, in some cases, for transit. In the many decades since, transportation modeling has become institutionalized in transportation agencies and reinforced through legislation. For example, the Clean Air Act Amendments of 1990 tightened certain transportation-air quality requirements, including those for demonstrating that transportation plans conform to air quality planning require- ments. The passage of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) renewed emphasis on the met- ropolitan transportation planning process. ISTEA strength- ened the role of MPOs by allocating funding to them and gave more flexibility and more decision authority to the local elected officials comprising their boards. At the same time, ISTEA reinforced the Clean Air Act (CAA) mandate for more tightly coordinated transportation and air quality planning. MPOs faced the threat of losing funds if they failed to show, through regional modeling, that their transportation plans and programs would neither exacerbate air pollution prob- lems nor delay attainment of national ambient air quality improvements. As a result, many MPOs took a hard look at their travel demand models and found them wanting. Together with federal agencies, the MPOs sponsored an investigation of the state of the art and the state of practice in transportation and air quality planning (Harvey and Deakin, 1992 a) and also sponsored a manual on best practices for transportation-air quality modeling (Harvey and Deakin, 1992 b). Both docu- ments aimed to help MPOs identify acceptable methods as well as to point out paths to more substantial modeling improve- ments. In addition, USDOT initiated in 1993 the Travel Model Improvement Program (TMIP), initially established as a part- nership with the Department of Energy and the Los Alamos National Laboratory and later evolving into a multifaceted center for training, information, and peer exchanges. From the Los Alamos partnership came the TRansportation ANalysis SIMulation System (TRANSIMS), an advanced travel mod- eling technology, as well as several demonstration projects on traffic micro-simulation and activity modeling. Also dur- ing this period, interest in formal land use modeling made a comeback among academics, and advances were made in the modeling of land developer decisions, household and business location choices, and the interactions of these choices with transportation systems. (See Anas, 1994, Abraham and Hunt, 1999; Waddell, 2002; Hunt and Abraham, 2003, for U.S. and Canadian examples of advanced models.) These efforts spurred many advances in transportation modeling. There was a growing recognition that travel demand is derived from the scheduling of activities dispersed over space and that modeling individual trips rather than travel was losing important information and likely introducing grave error, which led to the development of activity models. (See Bhatt and Koppelman, 2003, for a history of the intellectual development of activity models.) Representation of a daily schedule of activities and the resulting travel âtoursâ rather than individual trips became the new modeling paradigm for many researchers. Others made advances in the statistical estima- tion approaches used in modeling, aiming to reduce biases and increase theoretical robustness and flexibility. Still others moved forward on disaggregate models using individuals and house- holds as the units of analysis rather than population aggregates. Despite these efforts and continuing progress in develop- ing advanced models, practice is widely criticized for failing to 51 The history of modeling in this section draws in part upon work by Newmark and Deakin, 2011 (forthcoming). Interview findings and quotations are taken in part from work done for a study of analysis methods for transportation green- house gas reduction, Deakin 2011 (forthcoming).
38 adopt advances from research. Rodier quoted experts who âused words such as âdismal,â âprimitive,â âdisappointing,â and âdeficientâ to describe the state of [modeling] practice.â The 2007 TRB Special Report 288: Metropolitan Travel Forecasting commented that âEvery 10 years or so there begins a cycle of research, innovation, resolve to put innovation into practice, and eventual failure to effect any appreciable change in how travel forecasting is practiced.â The researchers scanned modeling practice and found that many of the larger MPOs have embarked on the implemen- tation of activity-based models in the last 5 years, and a few have also aimed to integrate these models with models of the regional economy and/or location and land use. However, the researchers also found that not a single state or regional agency had discarded its trip-based models and fully replaced them with activity-based models. Many of the MPOs are using a version of their trip-based models to do routine analyses and running their newer activity-based models for comparison purposes or, as one modeler put it, to see whether it gives dif- ferent results. Likewise, the researchers found that land use and location models are not run routinely, even in areas that have them. The 2007 TRB report identified several barriers to travel demand model innovation, among them budget limitations, fear of legal challenges in conformity analyses (which must track transportation system performance over time), and the pressures of day-to-day work. For some agencies these fac- tors led them to decide not to take on activity-based models at this time (see, e.g., VDOT, 2009). For others it led to the use of the more familiar trip-based models for day-to-day work, with the activity-based models being used for special studies. The review confirmed these barriers and suggested others: â¢ Uncertainty about performance and added value; â¢ Uncertainty about technical soundness; â¢ Gaps between research, practitioner, and policymaker needs; â¢ Significant technical requirements; and â¢ New skill mixes and inadequate staffing. A significant concern among practicing modelers is whether activity-based models, integrated transportation-land use models, and other advances really provide any practical improvement over trip-based models. Academics, consultants, and modeling staff from the largest MPOs agreed that activity- based models and integrated land use-transportation models were the state of the art, with stronger theoretical grounding and higher potential for accurately modeling individual and household behavior. However, the practitioners even at these large MPOs were not entirely convinced that the new models had produced better results than their previous models and noted that the complexity of the models made them more diffi- cult and time consuming to use, making their cost-effectiveness an issue. Practitioners also had concerns about the technical valid- ity of models. They argued that the activity-based modelers made many large and untested assumptions, for example, that a 1- or 2-day travel and activity diary would provide enough data for more sophisticated modeling. However, empiri- cal evidence sufficient to test complex models is extremely hard to obtain; many variables can affect measured activity and travel patterns, including population growth rates and socioeconomic characteristics of the population, employ- ment rates and total jobs, factor prices (e.g., price of gasoline for transportation, price of utilities for housing choice), and much more. Indeed, analysts often have to resort to additional modeling to understand the factors that led to observed out- comes. The lack of transparency into the performance of modeling innovations is thus a major issue. There also appears to be a gap between needs and ben- efits perceived by academics and by practitioners. Academ- ics argued that activity models are an improvement because their structure accords with far more reasonable behavioral assumptions than those embedded in four-step models. In addition, they argued, advanced models allow more rigorous investigation of many currently salient policies, e.g., the effects of congestion pricing on time of travel. Practitioners agreed, but expressed concern that the models need to produce regularly needed information (e.g., reasonably accurate forecasts of travel volumes, mode shares, and origin-destination patterns), as well and not just that they are theoretically sound or able to exam- ine innovative but infrequently considered policy options such as pricing. As one practitioner put it, âI understand that if we had congestion pricing, people might reschedule cer- tain activities to avoid peak tolls and that models that assume they must travel in the peak period will therefore overstate pricingâs effectiveness. But for [my agency] that is a research question, not a practical question [because] we arenât plan- ning to implement congestion pricing. That is not enough justification to wholesale change our practice.â Some also questioned whether advanced modeling was the right place to make investments. Federal and state officials questioned whether a transition to activity-based models would be effective for the smaller MPOs. MPO staff work- ing on regional strategic planning and investment program- ming, activities that require consensus building, questioned the importance of models. As one senior official put it, âThe models are useful to the extent that they offer insights, but we donât let the model results determine decisions.â Elected offi- cials also thought that models (and modelers) were too often hard to understand and sometimes were focused on details that did not matter so much to decisionmakers and oblivious to other issues that do matter to the elected.
39 Others argued for entirely different approaches to the devel- opment and use of models. One proposal was that researchers should be funded to develop and use models to better under- stand travel behavior, accumulating research results to allow generalizations, and then the results rather than the models would be used as input in formulating policies and plans based on collaborative planning. In this approach, modeling would be largely a research tool rather than a tool of practice, but research would better inform practice. Another proposal was to develop advanced models as research tools and to do peri- odic regional studies with them, but to develop transparent, easy-to-use, sketch planning methods that reflected the knowl- edge gained from these regional studies when doing everyday planning. The data requirements for developing and maintaining the models are also an issue, and both practitioners and model developers acknowledge that available data sources may not be up to the task. For example, advanced models often call for parcel-level land use data as well as multi-day activity surveys and link-by-link and lane-by-lane network data. Many practi- tioners find such data requirements to be daunting. The costs of the data are problematic as are concerns about quality. In addition, some agency staff were concerned that they did not have the expertise to collect and maintain the com- plex databases and would have to either contract for ongoing or repeated consulting services, hire new staff, or develop new in-house skills. For agencies that prefer to do much of their data and modeling work in house, the prospect of having to contract for assistance is not attractive; at the same time, many of the staffers the researchers talked with believed there was âno bandwidth left to take on new tasks.â Pavement Technologies Pavement serves nearly all modes of surface transporta- tion: automobiles, buses, bicyclists, and pedestrians all depend on smooth pavements to travel in comfort and safety. It is an essential component of the national surface transportation system and over $100 billion is spent annually in the United States on pavement (Fleming 2011). Most pavements are designed to last for 20 years (AASHTO 1998). However, pavement lifespan can be shortened in sev- eral ways: exposure to heavier than planned traffic volumes, high truck and heavy-duty vehicle shares of traffic, extreme weather, and extreme geologic conditions. Accelerated deterioration has both safety and cost implica- tions. Pavements in disrepair are hazardous to motor vehicles, bicycles, and pedestrians. Early repair requirements also stress transportation agenciesâ already stretched budgets, and agencies can face funding shortages for paving programs. Yet allowing pavements to continue to deteriorate can lead to higher long run costs from substructure repair or rebuilding. The high petroleum content of many pavements (both in the materials used and in the production process) has meant that pavement costs have increased with, and been volatile because of, the price of oil. Pavement design and choice of materials also have envi- ronmental and health consequences. Some pavement materi- als and designs are more noise and water polluting, affecting both humans and wildlife. Pavement production workers are exposed to fumes, particulate matter, and high temperatures. Manufacturing worker hazards are comparable with constant exposure to cement dust that causes eye, skin, and respiratory irritation (OSHA, 2004). Pavement has direct influences on the surrounding envi- ronment, including stormwater runoff, which leads to flood- ing and water pollution, and heat runoff, which causes thermal shock. Additionally, most energy used to produce transporta- tion construction materials comes from the production of pavement materials, and cement and asphalt production in particular is the largest source of industrial process-related CO2 emissions in the United States (Kalra et al., 2012). There is great opportunity to address safety, cost, system pres- ervation, and a host of environmental concerns with pavement innovations. As described in the next sections, much research has been dedicated to addressing these needs, but barriers to their adoption can be significant. The researchers reviewed examples of pavement technolo- gies that enhance agenciesâ abilities to manage pavement across their service area and technologies that improve the design of and materials used in pavements. Accurate estimates of pavement performance are crucial for maintaining pavement. Transportation agencies can use pavement management systems to integrate and analyze data about pavement condition and develop programs that effec- tively schedule pavement maintenance, construction, and other activities. This can reduce costs associated with delayed pavement repairs and reconstruction.52 NCHRP is developing a national mechanistic-empirical pavement design guide to improve pavement performance prediction. FHWA notes â[The guide] offers procedures for evaluating existing pavements and recommendations for rehabilitation treatments, drainage, and foundation improvements. In addition, the new guide incorpo- rates procedures for performing traffic analyses, includes options for calibrating to local conditions, and incorporates measures for design reliability. Engineers can use the guide to analyze common causes of pavement distress, including fatigue, rutting, and ther- mal cracking in asphalt pavements, and cracking and faulting in concrete pavementsâ (FHWA 2004). 52 In the case of Washington State, pavement quality increased from 50% of the pavement in good condition in 1970 to 94% in 2005 largely due to the use of the DOTâs pavement management system and state support to fund and implement projects at their lowest costs in the pavementâs lifecycle (FHWA, 2008a).
40 Innovations in pavement design and materials, include â¢ Superpave, a system for designing pavements, â¢ Warm-mix asphalt, â¢ Pavements made of recycled materials, â¢ Permeable pavements, â¢ Cool pavements, and â¢ Self-healing pavement. The Superpave system was developed in the 1980s to address two major concerns in asphalt pavement: rutting and low-temperature surface cracking. The Illinois Asphalt Pave- ment Association describes Superpave: Superpave is a comprehensive system for the design of paving mixes that are tailored to the unique performance requirements dictated by the traffic, environment (climate), and structural section at a pavement site. It enhances pavement performance through the selection and combination of the most suitable asphalt binder and aggregate. (IAPA) As such, Superpave may produce cost savings and increase pavement lifetime. Asphalt production typically occurs on site. It is very oil and labor intensive and requires very high mixing temperatures. This has cost, environment, and worker health impacts. Intro- duced in 2002 from Europe, warm-mix asphalt (WMA) helps address these concerns. WMA is a general term for asphalt technologies that reduce the mixing temperatures of regular hot-mix asphalt by 50 to 100 degrees Fahrenheit. Research shows that WMA is less expensive than HMA because of the reduced amounts of crude oil required. WMA also stretches the construction season, which can reduce project costs. WMA has furthermore shown improved performance on the road. FHWA has reported that WMA can improve field compaction, which can facilitate longer haul distances (FHWA 2008b). Pavements built with recycled materials are becoming a growing priority. Recycled materials may reduce life-cycle cost, landfill space, and fuel consumption and may reduce other environmental impacts (e.g., greenhouse gas emis- sions). Applying recycled materials for rehabilitation and new construction projects has been considered a priority for FHWA. Permeable pavements allow water runoff to percolate through the pavement and into groundwater sheds. Perme- able pavements are ideal for low-volume applications such as parking lots; however, care must be taken to ensure that the water runoff does not have significant levels of contaminants that then are channeled into other water resources. Cool pavements reflect solar radiation to reduce ambient temperatures, which can be particularly important in urban areas. Other benefits of cool pavements include reduced storm- water runoff, lower tire noise (due to porous material absorp- tion), and improved local comfort (with reduced temperatures) (U.S. EPA, a). Self-healing pavement has additives mixed into the asphalt or concrete that help seal cracks once they are formed. Origi- nating in Europe, research efforts in the United States have included self-healing polymers and self-healing cement mixers. Several barriers make it difficult for transportation agencies to effectively respond to technologies such as these. Barriers include â¢ Financial constraints, â¢ Federal restrictions on proprietary materials, â¢ Low-bid contracting practices, â¢ Constrained construction time, and â¢ Internal and industry inertia. Limited funding sources and rising capital costs pose signif- icant barriers to technology adoption. State and local agency interviewees expressed frustration in maintaining the qual- ity of their roads with reduced budgets. All of the interview- ees remarked on this growing problem of fiscal constraint, both for maintaining existing pavement as well as developing innovations. Low-bid contracting practices are also problematic. Trans- portation agencies often outsource construction and rehabil- itation to third-party contractors. Subject to project budget limitations, agencies select the lowest bids, which tend to not include total service life costs. This places the focus on immediate up-front costs without incorporating longer costs of the total service life of the pavement. Although some inno- vations reduce costs (e.g., WMA), others may increase the cost of pavement projects significantly. Complications from the low-bid practice may deter the implementation of newer innovations that have higher initial costs but might result in lower total costs (Caltrans, 2007). Federal restrictions on proprietary materials pose addi- tional barriers. As of 2006, FHWA âprohibits the expenditure of federal-aid funds on a federal-aid highway project âfor any premium or royalty on any patented or proprietary material, specification, or processââ (FHWA 23 CFR 635.411). One interviewee interpreted this restriction as preventing the use of specialized materials, even if they are most appropriate for the project. Another interviewee stated that it hindered but did not necessarily prevent use: âTechnically, the restriction doesnât prevent the useâif patented products are proposed, additional economic and engineering analysis is required to confirm the need of the proprietary product, so it doesnât prevent but limits the use.â Certain pavement materials cannot be laid in cold tem- peratures and can limit off-peak construction. For states with particularly cold winters, construction season is limited from March to September, concentrating user delay.
41 Finally, although innovations may yield benefits to agency staff, the public, or both, agency staff may resist incorporat- ing new practices to their jobs. Interviewees spoke of the dif- ficulty of transferring knowledge of innovations that may be more technically preferable but more complex than origi- nal practices. Also, the industry itself is seen as resistant to change. One interviewee summarized the prevailing perspec- tive of the industry as âif new, then no.â High fragmentation between some state DOT headquarters and field offices also was cited as a barrier for innovation distribution where head- quarters staff need to âconvinceâ the many districts to imple- ment a new technique or material. Summary of Barriers A synthesis of the four case studies suggests a set of com- mon barriers as shown in Table A-2. This set is not intended to be exhaustive or conclusive, but to highlight the range of technological and institutional challenges with which agen- cies contend in their efforts to respond to technology. Some barriers to technology assessment and adoption have to do with the technology itself. â¢ Technology Uncertainty. The performance of technology may be inherently uncertain (e.g., because the technology is not yet proven or has complex interactions with the trans- portation system that are difficult to anticipate and assess). This makes it difficult for agencies to weight the costs, ben- efits, and effects of technologies. Example from Case Studies: The technical validity of advanced transportation and land use models was a key concern of practitioners. â¢ Other Technical Barriers. There may be barriers inherent in a technology. Example from Case Studies: The use of several pavement innovations is limited by very cold winter climate in some regions. Many other barriers are institutional (i.e., an agencyâs own organization, culture, capacity, and resources may stand in the way of its engaging fruitfully in processes to identify, assess, shape, and adopt innovative technologies). â¢ Performance Assessment. Agencies (or their partners) may not have adequate skills, experience, or resources in accu- rately assessing the costs, benefits, and outcomes of technol- ogy adoption. They may also have insufficient objectivity in evaluating a technology. Example from Case Studies: Many interviewees expressed concerns that the developers of ITS applications also evaluate their performance and may not be objective evaluators. â¢ Standards, Rules, and Regulations. Agencies may adhere to technical standards, rules, and regulations that limit or hinder their ability to adopt technology. For example, although adhering to technical standards can encourage consistency, predictability, and assess ability; standards may hinder the adoption of innovations that are rapidly evolving and for which the development and adoption of standards cannot keep pace. Example from Case Studies: Confusion about the role of different standards and regulations hinders the adoption of CSS. â¢ Internal Organization and Culture. The steeply hierarchi- cal organizational structures often found in transportation agencies may make it difficult to bring together the correct mix of decisionmakers, technologists, managers, and other stakeholders. Projects may stall because their technology assessments were not fully communicated to decision- makers and agency staff. Agencies may not have a culture of innovation. Personnel may not have resources with which to be innovative or may not be rewarded for taking risks. Example from Case Studies: Reviews suggest that there may be significant inertia and conflicting values among staff that hinders the adoption of CSS. â¢ Inadequate Skill-Mix. Agencies may not have the required technical knowledge or the human resources to successfully assess and adopt technology. Example from Case Studies: Interviewees expressed signifi- cant concerns that agencies may not have technical expertise to evaluate or implement certain ITS projects. â¢ Technical Information. The information about a tech- nology may have shortcomings (e.g., if it is poorly com- municated). Example from Case Studies: Decisionmakers in ITS expressed frustration at the use of technical jargon in communicating about projects. Other barriers are created by the larger political, economic, legal, and social context in which agencies operate and can particularly affect the ability of agencies to assess and adopt technologies. â¢ Investment, Legal Requirements, and Markets. Uncer- tain or high deployment and maintenance costs, restric- tions on funding, and unfavorable market conditions may make it difficult for agencies to secure or use resources to successfully adopt technologies. Public agency contracting procedures such as stringent bidding requirements or inef- ficient bid/award rules may make it difficult for agencies to employ the best organizations and devices. Example from Case Studies: The emphasis on low-bid prac- tices has hindered agencies from using advanced pavements that may have lower life-cycle costs than other materials.
42 Barrier ITS CSS Transportation/ Land Use Models Pavements Technology Uncertainty â¢ Validity of models and assumpons Other Technical Barriers â¢ Data availability and reliability â¢ Climates limit implementaon of materials Performance Assessment â¢ Lack of objecve assessments â¢ Lack of or methodological shortcomings in assessments in broader social, economic, and legal context â¢ Controversy and over forecasng of impacts of CSS project â¢ â¢ Uncertainty about need and value added Lack of observability of model performance Standards, Rules, and Regulations â¢ Rapid change makes standards restricve â¢ Unclear relaonship between exisng and new standards â¢ Low-bid pracces prevent adopon of technologies with lower life- cycle costs Internal Organization and Culture â¢ â¢ Conflicng mission goals Separate ITS units may hinder implementaon Slow contracng processes Reluctance to take risks with public funds â¢ â¢ â¢ Conflicng mission goals Inera towards using CSS and conflicng internal culture Insufficient leadership â¢ Cultural resistance to new methods and processes Inadequate Skill-Mix â¢ â¢ â¢ Need for new skills â¢ â¢ â¢ â¢ Need for new skills Heavy exisng work loads Technical Information â¢ Use of jargon Investments, Legal Requirements, and Markets â¢ â¢ â¢ Insufficient aÂenon to legal issues Cutbacks on funds earmarked for ITS Implementaon paced by technology and system replacement cycles Fear of legal challenges in conformity analyses Budget limitaons â¢ â¢ â¢ Low-bid pracces prevent adopon of technologies with lower life- cycle costs Restricons on use of funds for proprietary materials and processes Limited sources of funding and rising capital costs Table A-2. Barriers identified in case studies. (continued)
43 Barrier ITS CSS Transportation/ Land Use Models Pavements Multi-Party Coordination â¢ Partnerships across agencies and with private sector necessary but difficult â¢ Need for cross- agency partnership â¢ Conflict between policy goals of elected officials and agency mission goals â¢ â¢ Differences in atude about CSS between staff across agencies Perceived "foot- dragging" in cross-agency approvals for projects â¢ Conflict between policy goals of elected officials and agency mission goals â¢ â¢ FragmentaÂon between DOT headquarters and field offices Headquarters staff need to âconvinceâ districts to implement new technique or material External Acceptance â¢ â¢ Difficulty assessing market value and acceptance Difficulty convincing users of value â¢ Conflict with local stakeholder interests Table A-2. (Continued). â¢ Multi-Party Coordination. Deploying almost any technol- ogy requires consensus from many parties, and there may not be established processes to build consensus or resolve stalemates, particularly when agencies and organizations have conflicting policy objectives. Example from Case Studies: ITS projects often require but are hindered by coordination between transportation agencies, local governments, private companies, and public groups. â¢ External Acceptance. The success of technology also depends on consumer preferences, which may not be aligned with technological offerings because of alternative preferences or cultural and social norms that work against a particular technology application. Also, users may not be familiar with or educated about particular technologies or misunderstand their risks and benefits. These barriers can arise at various times during project development, from the initial inception of an idea to deployment. Example from Case Studies: CSS projects faced difficulty in implementing street redesign projects because of dissatis- faction from local business owners, neighborhoods, and other stakeholders, despite strong outreach efforts. Response to Barriers What can be done about these barriers, if transportation agencies decide it is important to remove them? In addition to more resources (e.g., more funding for implementation and technical training for staff), some of the strategies identified in the literature and in the case studies include â¢ Development of a legal, institutional, and political envi- ronment that is willing and able to run trials, carry out test projects, and learn from them, coupled with an ability to accept failure of test products or processes as a cost of innovation rather than treat failure as a punishable offense. â¢ Strategic planning for innovations, including identifying opportunities, constraints, competing options, likely mar- ket shares, costs and benefits, returns on investment, and potential partners. â¢ Strategic assessment of agency capacity for development or adoption of the innovation. This includes determining who has authority, what they can do, when/how fast they can move, where they have jurisdiction, why they would be motivated to act, how they can move forward (i.e., assess- ment of compatibility of the innovation and its development and implementation process with the agencyâs resources, capabilities, values, and priorities). â¢ Internal management of change: look for potential internal conflicts as a result of moving forward, in order to clarify expectations and set clear priorities (eliminate conflicts or provide decision rules and a timeline for decisions when there are different values and approaches). â¢ If an agency is interested but cannot move on its own because of institutional constraints or priorities, looking
44 for partners who can â or finding other ways to provide support (e.g., helping to fund research and development carried out by others) with more flexibility. â¢ Recognizing different partner roles (e.g., as sources of inno- vation, developers of innovation, independent evaluators of innovation). â¢ Use of pilots, test markets, and demonstration projects to explore options at relatively low cost. â¢ Consultation with the product or process users to assess the market, identify potential problems, identify user-led innovations, and adjust products in a cycle of learning and improvement. Use of external reviewers, committees of peers, and other peer review to help make sure decisions are rational and high quality. â¢ Adopt enhanced contracting methods. This includes per- formance specifications and longer warranties in contractor performance contracts that demand levels of performance for a certain number of years and penalize contractors if those specifications are not met. It also includes the use of design-bid-maintain projects that allow the contractors the flexibility to design their perceived best bid for a certain project. â¢ The federal restriction for projects using federal funding on not allowing patented materials (FHWA 23 CFR 635.411) can be improved to reduce the required analysis needed to support use of such materials. â¢ Ongoing outreach and marketing in identifying the impor- tance of smooth streets can increase the awareness of the cost and importance of pavement projects. â¢ Incentive programs to encourage innovation also could be pursued, particularly with respect to research, best practices, and lessons learned abroad. In addition to removing any barriers that may hinder innovative products from entering the marketplace, government has incentivized contractors and agencies in using certain innovations that have proven effectiveness.