Skip to main content
eScholarship
Open Access Publications from the University of California

The Institute of Transportation Studies at UC Berkeley has supported transportation research at the University of California since 1948. About 50 faculty members, 50 staff researchers and more than 100 graduate students take part in this multidisciplinary program, which receives roughly $40 million in research funding on average each year. Alexandre Bayen, Professor of Civil and Environmental Engineering and Professor of Electrical Engineering and Computer Science, is its director.

Cover page of Integrating Traffic Network Analysis and Communication Network Analysis at a Regional Scale to Support More Efficient Evacuation in Response to a Wildfire Event

Integrating Traffic Network Analysis and Communication Network Analysis at a Regional Scale to Support More Efficient Evacuation in Response to a Wildfire Event

(2021)

As demonstrated by the Camp Fire evacuation, communications (city-to-city, city-to-residents) play important roles in coordinating traffic operations and safeguarding region-wide evacuation processes in wildfire events. This collaborative report across multiple domains (fire, communication and traffic), documents a series of simulations and findings of the wildfire evacuation process for resource-strapped towns in Northern California. It consists of: (1) meteorological and vegetation-status dependent fire spread simulation (cellular automata model); (2) agency-level and agency-to-residents communication simulation (system dynamics model); and (3) dynamic traffic assignment (spatial-queue model). Two case studies are conducted: one for the town of Paradise (and the surrounding areas) and another for the community of Bolinas. The data and models are based on site visits and interviews with local agencies and residents. The integrated simulation framework is used to assess the interdependencies among the natural environment, the evacuation traffic and the communication networks from an interdisciplinary point of view, to determine the performance requirements to ensure viable evacuation strategies under urgent, dynamic wildfire conditions. The case study simulations identify both potential traffic and communication bottlenecks. This research supports integrating fire, communication and traffic simulation into evacuation performance assessments.

Cover page of Benchmarking “Smart City” Technology Adoption in California: Developing and Piloting a Data Collection Approach

Benchmarking “Smart City” Technology Adoption in California: Developing and Piloting a Data Collection Approach

(2021)

In recent years, “smart city” technologies have emerged that allow cities, counties, and other agencies to manage their infrastructure assets more effectively, make their services more accessible to the public, and allow citizens to interface with new web- and mobile-based operators of alternative service providers. This project reviews the academic literature and other sources on potential strengths, weaknesses, and risks associated with smart city technologies. No dataset was found that measures the adoption of such technologies by government agencies. To address this gap, a methodology was developed to guide data collection on the adoption of smart city technologies by urban transportation agencies and other service providers in California. The strategy used involved webscraping; interviews with experts, public agency, and senior level staff; and consultations with technology vendors. The approach was tested by assembling data on the adoption of smart city technologies in California by municipalities and other local public agencies.

Cover page of Evaluation of Coordinated Ramp Metering (CRM) Systems in California

Evaluation of Coordinated Ramp Metering (CRM) Systems in California

(2021)

Freeway on-ramp metering (RM) has been extensively used as a traffic control strategy to regulate the entry of the on-ramp vehicles to prevent congestion at the freeway merging areas and preserve the freeway capacity. Benefits of RM include improved freeway travel times, improved travel time reliability, and accident reductions. Fixed-rate ramp metering strategies are based on historical data and implemented by time of day. Traffic responsive RM strategies are based on real time freeway traffic data provided by loop detectors at the vicinity of the on-ramp. Coordinated RM determine the metering rates at the ramps along a freeway corridor to minimize the delays or maximize the freeway throughput. The objective of this research was to evaluate the traffic performance of coordinated traffic responsive systems (CRM) currently implemented by Caltrans based on field data.

Cover page of To Pool or Not to Pool? Understanding the Time and Price Tradeoffs of OnDemand Ride Users – Opportunities, Challenges, and Social Equity Considerations for Policies to Promote Shared-Ride Services

To Pool or Not to Pool? Understanding the Time and Price Tradeoffs of OnDemand Ride Users – Opportunities, Challenges, and Social Equity Considerations for Policies to Promote Shared-Ride Services

(2021)

On-demand mobility services including transportation network companies (also known as ridesourcing and ridehailing) like Lyft and Uber are changing the way that people travel by providing dynamic mobility that can supplement public transit and personal-vehicle use. However, TNC services have been found to contribute to increasing vehicle mileage, traffic congestion, and greenhouse gas emissions. Pooling rides ⎯ sharing a vehicle by multiple passengers to complete journeys of similar origin and destination ⎯ can increase the average vehicle occupancy of TNC trips and thus mitigate some of the negative impacts. Several mobility companies have launched app-based pooling services in recent years including app-based carpooling services (e.g., Waze Carpool, Scoop) that match drivers with riders; pooled on-demand ride services (e.g., Uber Pool and Lyft Shared rides) that match multiple TNC users; and microtransit services (e.g., Bridj, Chariot, Via) that offer on-demand, flexibly routed service, typically in larger vehicles such as vans or shuttles. However, information on the potential impacts of these options is so far limited. This research employs a general population stated preference survey of four California metropolitan regions (Los Angeles, Sacramento, San Diego, and the San Francisco Bay Area) in Fall 2018 to examine the opportunities and challenges for drastically expanding the market for pooling, accounting for differences in emergent travel behavior and preferences across the four metropolitan regions surveyed. The travel profiles, TNC use patterns, and attitudes and perceptions of TNCs and pooling are analyzed across key socio-demographic attributes to enrich behavioral understanding of marginalized and price sensitive users of on-demand ride services. This research further develops a discrete choice model to identify significant factors influencing a TNC user’s choice to pool or not to pool, as well as estimating a traveler’s value of time (VOT) across different portions of a TNC trip. This research provides key insights and social equity considerations for policies that could be employed to reduce vehicle miles traveled and emissions from passenger road transportation by incentivizing the use of pooled on-demand ride services and public transit

Cover page of Summary of Interviews with California Metropolitan Planning Organizations About Senate Bill 375 and the Sustainable Communities Strategies

Summary of Interviews with California Metropolitan Planning Organizations About Senate Bill 375 and the Sustainable Communities Strategies

(2021)

In July and August of 2020, a research team of four graduate students from UC Berkeley’s Department of City and Regional Planning conducted interviews with directors and other high-level staff representing several of California’s metropolitan planning organizations (MPOs) to gather information on the achievements and challenges associated with the implementation of SB 375. Key takeaways from this effort include: 1) MPOs are not requesting additional authorities or oversight of local land use decisions; 2) MPOs use funding as “carrots” to incentivize local plans to align with regional goals, and many MPOs desire more discretionary funding and priority-specific funding; 3) some MPOs want to focus on greenhouse gas (GHG) strategies, such as telecommuting, active transportation, and technological advancement, in order to meet their GHG emission targets; 4) MPOs want the State to develop policies in ways that acknowledge distinct planning nuances and economic and geographic contexts across regions; 5) the process of developing and submitting regional plans to the State for review is staff-intensive and technically complex for MPOs, which takes away from the agencies’ capacity to focus on implementation and other work; 6) Senate Bill 375 has empowered MPOs to consider more deeply the relationship between land use and transportation; and 7) as a result of Senate Bill 375, there is now increased communication and engagement between the MPO and a broader set of stakeholders

Cover page of Future of Public Transit and Shared Mobility: Scenario Planning for COVID-19 Recovery

Future of Public Transit and Shared Mobility: Scenario Planning for COVID-19 Recovery

(2021)

In 2020, the novel coronavirus (COVID-19) pandemic enveloped the world, leading to a public health crisis that profoundly changed allaspects of society, especially multiple sectors in transportation such as public transit and shared mobility. With so much uncertaintyabout the future of travel, the transportation sector needs to move rapidly to shape the nature of public transit and shared mobilityservices during the COVID-19 recovery period. Consequently, the University of California Institute of Transportation Studies (UC ITS) and the Transportation Research Board’s (TRB) Executive Committee launched a scenario planning exercise from June to September 2020 involving 36 transportation experts. The exercise resulted in a series of policy options and research directions across three timeframes (i.e., within 12 months, one to three years, four to six years) that could guide the recovery of the public transit and shared mobility industries. This report offers several key takeaways. First, external forces beyond COVID-19 (e.g., economy, political will, etc.) will significantly drive the future of public transit and shared mobility and determine the effectiveness and feasibility of any policy strategies. Second, while public transit and shared mobility face a dire future in the short run, steps can be taken immediately to reduce the effects of the current crisis, while also laying the groundwork for more sustainable transportation in the future beyond COVID-19. Actions taken to only address the current crisis will not prepare public transit and shared mobility for the future. Finally, future policies and actions will not be effective without in-depth analysis and development. Research and lessons learned from demonstration and pilot projects will be critical for crafting policies, identifying all positive and negative outcomes, and shaping actions toward a future transportation system that is more resilient, socially equitable, and environmentally friendly.

Cover page of The Impact of COVID-19 on the Mobility Needs of an Aging Population in Contra Costa County

The Impact of COVID-19 on the Mobility Needs of an Aging Population in Contra Costa County

(2020)

In 2018, SafeTREC conducted a survey on transportation mobility issues among older adults in California. A follow-up survey planned for 2020, just as the COVID-19 pandemic changed life for all residents, was redesigned to assess mobility needs and changes during the Shelter-in-Place order and focused on COVID-19 impacts. Results indicate that the COVID-19 pandemic and subsequent Shelter-in-Place order have had a major impact on senior mobility. Communications for many were restricted to phone, email, texts, social media and video chats. Among those with a medical problem, just over 60% called a doctor or nurse line or went to a doctor’s office, while 11.2% went to an emergency room, and 8.6% did nothing. A total of 8% of respondents said they had run out of food or other important items during the Shelter-in-Place order. Rates of exercise outside the home dropped 20% between January and June 2020, and while over 60% sought outside entertainment in January 2020, by June 2020, nearly 70% accessed their entertainment online at home. Almost 80% of working respondents feared spreading or contracting COVID-19 because of their work or related transportation. Almost 20% felt a lack of companionship or closeness sometimes or often. Over 30% were worried about their current or long-term finances. A total of 84.5% strongly agreed or agreed that the Shelter-in-Place order was necessary. None of the respondents to the follow-up survey were diagnosed with COVID-19, and 88.2% were not concerned about risk of exposure from any member of their household.

Cover page of Examining the Potential for Uber and Lyft to be Included in Subsidized MobilityPrograms Targeted to Seniors, Low Income Adults, and People with Disabilities

Examining the Potential for Uber and Lyft to be Included in Subsidized MobilityPrograms Targeted to Seniors, Low Income Adults, and People with Disabilities

(2020)

Public agencies have subsidized taxi rides for people who have difficulty driving a car or using the regular transit system – targeting older residents and people with disabilities. There is interest among public agencies to add transportation network companies (TNCs), such as Uber and Lyft, to subsidized ride programs as a travel option due to the widespread availability of TNCs and high-quality service. Key issues include the need for wheelchair accessible vehicles, subsidy needs, and clients who lack or are uncomfortable using a smartphone and credit card. This research included a review of programs nationwide and interviews with program managers and clients to identify best practices. Best practices from agencies included contracting for wheelchair accessible TNC services, offering classes to help clients learn how to use the needed technologies, arranging for prepaid debit cards, creating a centralized billing system, providing a concierge service for those who need extra assistance, and setting subsidies based on need. Other recommended practices include providing high travel needs coverage, developing straightforward pricing structures, and not imposing restrictions on trip distance or trip purposes eligible for subsidy.

Cover page of Best Practices for the Public Management of Electric Scooters

Best Practices for the Public Management of Electric Scooters

(2020)

This research projects evaluates the social, environmental, and safety impacts of shared electric scooters (e-scooters)’ through a literature review, a nationwide scan of state and local laws and regulations, and a case study of Oakland’s experience with e-scooters, including an analysis of the city’s user survey and our own in-depth interviews. E-scooters offer an enjoyable, low-cost travel option, but are used mainly by young, affluent, white males. To improve equity, cities are requiring e-scooter rental companies to serve low-income and minority communities and some further mandate that a share of the e-scooters accommodate people with disabilities. E-scooters are quiet and produce no tailpipe emissions, but their cumulative environmental impact depends on their manufacture, useful life, disposal, and use. In early applications, rental e-scooters survived less than a year. Some 30-50 percent of e-scooter trips replace short auto trips. Cities and states can improve e-scooter safety by encouraging helmet use, offering rider training, limiting speeds, improving pavements, managing parking, and calming traffic.

Cover page of Synthesis of State-Level Planning and Strategic Actions on Automated Vehicles: Lessons and Policy Guidance for California

Synthesis of State-Level Planning and Strategic Actions on Automated Vehicles: Lessons and Policy Guidance for California

(2020)

This synthesis provides a summary and comparative analysis of actions states across the United States are taking inresponse to automated vehicles (AVs). The research focuses on state-level stakeholder forums (e.g., task forces, committees) and state-level strategic actions (e.g., studies, initiatives, programs) initiated by a state legislature, agovernor, or a state agency. The analysis found that AV stakeholder forums and strategic actions address a diverse set offocus areas, but they pay minimal attention to the implications of AVs on the environment, public health, social equity, land use, public transit, goods movement, and emergency response. Also, forums and strategic actions commonly include members from state transportation departments, the legislature, and academia; however, representatives from industry and non-governmental organizations (NGOs) are included less often. Academia and researchers participate in themajority of AV forums and actions, either in an advisory capacity (i.e., sharing expertise and experience) and/or through conducting research. Based on this analysis, the synthesis concludes with a recommendation for California to form a state-level working group representing leaders from the public sector, industry, NGOs, and academia to advise the Governor and the Legislature on AV policy across a range of focus areas.