Institute of Transportation Studies

In many evacuations including wildfire evacuations, public agencies often do not have enough resources to evacuate and shelter all citizens. Consequently, we propose that the sharing economy, through private companies and/or private citizens, could be leveraged in disasters for transportation and sheltering resources. To assess this feasibility, we distributed surveys to individuals impacted by three major wildfires in California: 1) the 2017 October Northern California Wildfires (n=79), 2) the 2017 December Southern California Wildfires (n=226), and 3) the 2018 Carr Wildfire (n=284). Using these data, we find that private citizens are moderately to highly likely to share transportation and sheltering resources in future disasters, but numerous reservations persist about sharing. We also find significant spare capacity in evacuating vehicles and potential homes. To supplement this work, we also conducted four focus groups (n=37) of vulnerable populations to determine the benefits and limitations of a sharing economy strategy in terms of equity. Groups included low-income (2017 December Southern California Wildfires), older adult (2017 October Northern California Wildfires), individuals with disabilities (2017 October Northern California Wildfires), and Spanish-speaking (2018 Mendocino Complex Wildfire). We find that while severe equity limitations exist, groups were able to develop several recommendations for successfully leveraging sharing economy resources for the general population and their specific vulnerable group. We conclude with several local agency and statewide recommendations for building a sharing economy framework for California to prepare for future evacuations.

We investigate the impacts of a combination of incentives on the purchase decisions of electric vehicle (EV) buyers in California from 2010 through 2017. We employ a comprehensive survey on over 14,000 purchasers of EVs in California. The survey covers a range of purchase intentions, general demographics, and the importance of various incentives. Our results indicate that the most important incentives for plug-in electric vehicle (PEV) owners are the federal tax credit, the state rebate, and HOV lane access. In addition, the importance of the incentives and their associated effect on purchase behaviour has been changing over time: respondents are more likely to change their decisions and to not buy a vehicle at all as time passes and the technology moves away from early adopters.

The mobility needs of an aging population is one of the most substantial challenges facing California in the coming decades. The number of residents age 65 and older is expected to double between 2012 and 2050, and the number age 85 and above is expected to increase by over 70% between 2010 and 2030. Declines in physical function related to age may reduce mobility options dramatically. A survey of 510 residents age 55 and older in Contra Costa County was conducted to determine mobility patterns and limitations related to age and other factors. Results of the survey indicate that a majority of seniors are car dependent. However, some older adults miss important activities due to mobility limitations associated with increasing age, poorer health, living alone, not having a licensed driver in the household, and having a disability. Mobility options are also limited in some geographic areas and demographic groups. Importantly, older adults want to “age in place.” Based on these findings and those in related studies, the travel options and the quality of life for older adults, now and in the future, can be greatly enhanced if efforts are made to develop mobility solutions beyond use of private vehicles. The findings support the recommendations of recent regional plans such as the Coordinated Public Transit–Human Services Transportation Plan (2018), adopted by the Metropolitan Transportation Commission (MTC) of the San Francisco Bay Area, which recommends supporting a range of mobility options centered around shared mobility and accessibility for populations at risk for limited mobility.

California’s housing crisis has spurred residential displacement of low income households from its high-cost coastal regions. Yet little is known about the transportation costs of displacement. As low income households are displaced from high to lower cost areas that may lack high quality transit options, one may expect them to shift transportation modes, have longer commutes and pay more of their income for transportation. This study aimed to pilot several data collection instruments in an effort to design a larger study on the transportation costs of displacement. We attempted to recruit people who were about to be evicted to download a GPS app on their phone and answer two surveys about their travel patterns and other characteristics before, during and after their eviction. After seven months of active recruitment, partnering with eviction defense organizations, we terminated the study without having collected any data. Ultimately we believe a lighter touch study would have been more successful and that it may have been too much to ask a person undergoing what may be considered a traumatic life event to install a GPS tracking app on their phone and dedicate several hours and emotional energy to a study. The need to characterize the transportation costs of displacement, however, is still important and we believe a shorter retrospective survey may be a more appropriate data collection method to pilot.

The survey project described here is intended to be the beginning of a multi-year project on the effectiveness of various activities in growing consumer interest in purchasing BEVs in the Sacramento region.

This survey in Sacramento shows that engagement in PEVs is moderate, based on the following results: 50% of respondents had seen some PEV-related advertising, mostly on television or in print media; 47% were aware of the California Clean Vehicle Rebate, and 46% aware of the federal tax credit; 40% could correctly name a PHEV, and 50% a BEV; 25% had sought out information on PEVs, mostly through the internet or speaking to car salespeople, friends, or family. Compared to respondents to a 2014 state-wide survey, a higher percentage of respondents to this 2018 Sacramento survey had seen charging stations, and a similar percentage, 3.3%, had actively shopped for a BEV. Ordinal logistic regression modelling indicated that the following factors were associated with having considered purchasing a BEV: being enthusiastic about PEVs, knowing someone by name who owns a PEV, having sought out information on PEVs, knowing how to refuel a PEV, and being familiar with the vehicles. Considering a BEV purchase was not associated with: having seen advertising, being aware of ride-and-drive events, having been in a PEV, having seen chargers, awareness of incentives, or the density of PEVs or charging stations near the respondent’s home.

Results suggest that respondents who are interested in BEVs are a self-selecting group whose interest is not the result of promotional activities. Existing efforts to engage the general population not yet had a significant impact on respondents thinking about purchasing a BEV. Future follow-up surveys will be able to track changes in respondent awareness, the impact of various advertising and awareness campaigns, and growing consumer engagement in PEVs over time.

We currently know little about what to expect regarding ride-pooling in shared automated vehicles (SAVs). Who will be willing to share rides, with whom, and under what conditions? This report details the efforts and results funded by two seed grants that converged on these questions. A broad-based literature review and review of automated vehicle (AV designs) leads to the articulation of potential risks and benefits of the pooled SAV experience and potential design solutions and supports, respectively. Risks could be related to compromised personal space, security, control, and convenience. Design features that might mitigate these risks include large windows to afford a high degree of visibility into and out of the vehicle, spacious seating and legroom (relative to larger shared vehicles like buses, trains, and planes), access to a remote human administrator who can observe inside the vehicle at all times, easy means to program private stops that are nearby one’s ultimate origins and destinations (to maintain privacy), and options for large groups or associations to “own” a particular vehicle (e.g., a female only SAV). Benefits of pooled SAVs could be related to restoration and social capital. Design features that could support these benefits include themed interiors; quizzes, games and ambient entertainment; augmented reality windshields; flexible seating allowing riders to face each other; accommodations for food and drink; ensuring broad access; and making SAVs a canvas for local art. The reports ends with a proposed research agenda highlighting the importance of qualitative engagement with consumers to understand the issues related to: switching to pooled SAVs from various dominant travel modes (e.g., private cars, ride-hailing, public transit); leveraging analogous modes (e.g., pooled ride-hailing) to study the potential of pooled SAVs; and conducting experiments to understand the influence of various features of the pooled SAV experience that will impact consumer adoption. This report can inform SAV designers, policy-makers, private transit service providers, and other stakeholders about behavioral and design factors that will impact uptake of pooled SAVs.

In this project, a novel approach has been developed to estimate the traffic states on arterial road links controlled by signalized intersections using both loop detector data and signal phasing information. We derived a trapezoidal fundamental diagram that includes two occupancy thresholds to categorize the traffic states into three different regimes: uncongested, congested, and downstream queue spillback. The parameters used to compute these two thresholds are closely related to road geometry, detector layout, signal settings, and vehicle dynamics, which can be obtained from the field data.  A case study was performed using field data from three intersections along Huntington Drive in the City of Arcadia in the I-210 Connected Corridors pilot. Flow-occupancy relations were obtained for both advance and stopline detectors at the intersection approaches, and it was found that advance detector information is more reliable because it is less impacted by the traffic signal.  The proposed trapezoidal fundamental diagram was validated using a dataset with six months of detector data.

The California Budget Act of 2016 included a provision to “complete a post-implementation review of the Project Resourcing and Schedule Management (PRSM) information technology system upgrade completed by the Department of Transportation”. The PRSM system referenced is Commercial-Off-The-Shelf (COTS) software deployed at Caltrans in 2014 and intended to enable Caltrans to effectively plan State employee and consultant time spent on activities related to projects in its Capital Outlay Support (COS) program. A team of researchers in the Engineering Project Management Program at UC Berkeley was selected to conduct the review of PRSM. This report summarizes the team’s findings. Looking inside Caltrans at how the agency is using PRSM, Section I reports on the researchers’ review of Caltrans documents and the interviews they conducted with sample groups of Caltrans staff. The study shows that PRSM has become a well-established system: it is now used agency-wide by approximately 3,000 Caltrans users with read/write access and many others with read-only access. Caltrans staff are using PRSM for project resourcing, especially for annual budgeting, but are not using all its scheduling functions to their potential. Looking outward for practices different from those of Caltrans that may reveal opportunities to improve Caltrans’ project management practices with PRSM support, Section II reports on findings from the researchers’ scan of comparable software, survey of state departments of transportation, interviews with private engineering firms, and review of recent developments and best practices in project management. The study shows that PRSM is but one of several possible- but still among the most highly-rated software system choices. Study recommendations include: continuing with ongoing PRSM training for District personnel to ensure consistency in use across the State, engaging more directly with the system vendor to voice Caltrans’ needs for future software enhancements, changing the current Caltrans workflow to include systematic project baselining, and developing task management practices using the Last Planner® System to enhance work flow reliability and thereby improve efficiency and project performance. This Report ends with a summary of all findings and lays the foundation for scope to be pursued in subsequent, applied research with Caltrans, aiming to further leverage the support that PRSM use can provide in its project management practices.

This report lays the groundwork for Metropolitan Transportation Commission – Association of Bay Area Governments (ABAG-MTC) as they develop a Priority Production Area (PPA) program. The PPA program will include locally designated industrial zones and seek to identify resources for these areas, while recognizing the need to balance land uses and that creating housing across the Bay Area is of primary importance. This study initiated outreach and engagement with local jurisdictions and experts to gain a better understanding of how local jurisdictions define their industrial space, how well current zoning works for their industrial land users, and the degree to which a PPA designation could help with business operations, retention or shaping the area’s future development. This report synthesizes input received as part of this engagement. Given that the PPA program is an action item of Plan Bay Area that integrates transportation and land use management into its long-range plan in an effort to meet greenhouse gas reduction targets, addressing the transportation needs associated with industrial lands could be a central component of the PPA program. Therefore, this report also explores both goods movement and worker accessibility challenges mentioned by city staff and experts and recommends how these PPA program could address these issues. Going forward, ABAG-MTC will need to prioritize the suggestions and ideas generated through this initial outreach process and determine which challenges and needs can feasibly be addressed with the PPA program.