The processes in the pavement life cycle can be defined as: material extraction and production; construction; transport of materials and demolition; the use stage, where the pavement interacts with other systems; the materials, construction, and transport associated with maintenance and rehabilitation; and end-of-life. Local governments are increasingly being asked to quantify greenhouse gas emissions from their operations and identify changes to reduce emissions. There are many possible strategies that local governments can choose to reduce their emissions, however, prioritization and selection of which to implement can be difficult if emissions cannot be quantified. Pavement life cycle assessment (LCA) can be used by local governments to achieve the same goals as state government. The web-based software environmental Life Cycle Assessment for Pavements, also known as eLCAP has been developed a project-level LCA tool. The goal of eLCAP is to permit local governments to perform project-level pavement LCA using California specific data, including consideration of their own designs, materials, and traffic. eLCAP allows modeling of materials, transport, construction, maintenance, rehabilitation, and end-of-life recycling for all impacts; and in the use stage it considers the effects of combustion of fuel in vehicles as well as the additional fuel consumed due to pavement-vehicle interaction (global warming potential only). This report documents eLCAP and a project that created an interface for eLCAP that is usable by local governments.
Transportation access is a significant issue in low-income, rural, and otherwise underserved communities in the US, with few affordable and reliable alternatives to car ownership. Carsharing is one promising alternative to improve access among marginalized communities. Grant programs in California have funded pilot electric carshare services. But little is known about the long-term financial sustainability of these services and how their costs and revenues compare those of transit. In this study, a financial model was used to estimate the net operating income (fare revenue minus costs) for Míocar, an electric carsharing service in marginalized suburban and rural communities. The estimated net operating income per month was −$1561, under current operating conditions, and ranged from −$1255 to −$1623 depending on simulated changes to fleet size, pricing, and usage rates. These negative net operating incomes correspond to a shortfall (or need for subsidies) of 68% to 92% of operational costs. Míocar could achieve a higher ratio of fare revenues to operational costs (13%) than existing transit (3 to 8%). To minimize required subsidies, electric carshare operators and prospective carshare communities should carefully consider hub locations (which can affect usage rates), the number of vehicles per hub, and the expected demand over time.
Recent studies suggest that there could be significant value to electric vehicle (EV) drivers and power companies from incorporating EVs into the state’s electrical power grids, known as Vehicle-Grid Integration (VGI). However, the benefits could be highly variable depending on the location of the utility territory, vehicle type and battery capacity, the relevant timeframe, and whether the connection involves only managed charging or includes bidirectional charging permitting vehicle to grid (V2G) power transfer, and other factors. Various studies conducted to date generally conclude that the opportunities for V2G could have two to three times the value of managed (or “smart”) charging. However, there are considerable additional complications for grid integration, including variable and site-specific implementation costs. Some savings such as deferring distribution system upgrades can be very significant but are also site-specific and depend on the level of curren and projected demands for electric power on the individual distribution feeder lines, and are therefore difficult to predict.
Reducing vehicle miles traveled (VMT) is a central plank of climate policy in California. VMT, however, has proved stubbornly resistant to policies to reduce it. While urban growth has become more compact and public transit service levels have been maintained or increased, these positive trends have not translated into less driving. This report argues that substantial reductions in vehicle travel in congested urban regions can only be achieved through reducing road capacity. It may be difficult to achieve substantial reductions in vehicle travel by relying solely on public transit, walking and cycling, and land use planning for compact, mixed-use development without an equal emphasis on limiting road capacity expansions, and even reducing current capacity.
Personal safety concerns continue to be one of the most critical issues among transit riders and women and gender minorities in particular. These safety concerns stem from the experience of sexual harassment that people who identify as women face frequently. While harassment can be a common occurrence, the vast majority of these experiences go unreported to transit agencies, leaving agencies without information about the magnitude of this problem on their system. This report details work with the San Francisco Municipal Transportation Agency (SFMTA) in their efforts to understand and address this problem. The SFMTA, working with two UCLA graduate students, designed a survey that drew from previous survey efforts and was tailored to address their interests and needs. This report documents the process of developing and deploying the questionnaire, in an effort to help other agencies take the first steps to better understanding rider safety and harassment. Through breaking down SFMTA’s approach, this report intends to inspire andinform similar efforts at other agencies.
Bicycle level of service (BLOS) is an essential performance measure for transportation agencies to monitor and prioritize improvements to infrastructure, but existing measures do not capture the nuance of facility differences on the state highway system. However, with the advancements in virtual reality (VR) technology, a VR bicycle simulator is an ideal tool to safely gather user feedback on a variety of bicycling environments and conditions. This research explored the benefits and limitations of using a VR environment to assess individuals’ bike infrastructure preferences. We conducted a bicyclist user experience survey in person on SafeTREC’s VR bicycle simulator and online and compared the results. The online survey consisted of showing participants pairs of VR videos of biking scenarios and asking them to choose the one that they preferred. To validate the online survey responses, we conducted in-person experiments with a VR bike simulator using the same pairs of videos. Our analysis indicates that 63 percent of the responses were consistent while a smaller percentage of responses (37 percent) changed after the simulator ride due to better perception provided by the simulator virtual environment. The outcome of this study helped to validate the online survey responses of the study.
The COVID-19 pandemic forced transit agencies to quickly adapt to new challenges, with service reductions as part of the response to reduced ridership, rising fiscal pressures, and staffing shortages. However, approaches to service adjustment varied significantly across agencies. While pandemic research often focuses on ridership impacts, less attention has been given to how transit service changes affected accessibility and equity. This study examines the impacts of pandemic service adjustments made by three major San Francisco Bay Area transit agencies on accessibility and equity, which is important to address given the absence of formal requirements for equity evaluation of temporary service changes. Using publicly available transit schedule and census data, metrics for transit service levels, job accessibility, and accessibility inequality were developed and used to trace changes from 2020 to 2023. The findings reveal distinct approaches to service reduction and restoration, with agencies prioritizing service differently based on travel needs and racial/ethnic minority populations. While equity briefly improved for some agencies during thepandemic, these changes were temporary, with all agencies returning to their pre-pandemic states of inequity. These insights can guide transit agencies in developing equitable service adjustment strategies and highlight the need for decision-making tools to help transit operators balance competing needs and respond flexibly to disruptions.
The aviation sector in California is facing increased pressure to reduce its carbon footprint, leading to a growing interest in alternative fuel aviation (AFA) technologies such as sustainable aviation fuel (SAF), as well as electric- and hydrogen- powered aircraft. The report develops a California Aviation Energy Model (CAVEM), examining various AFA technologies and analyzing possible policy options. The analysis emphasizes the importance of SAF in the short term, with projections indicating sufficient supply for intrastate flights and capped vegetable oil-based fuel consumption. Long-term efforts are focused on electric and hydrogen-powered aircraft, which remain in the early stages of development. Electrification of intrastate flights is deemed feasible, with estimated electricity consumption amounting to a small percentage of overall electricity generation. The report highlights the necessity for additional policy incentives (such as tax exemptions) and a comprehensive policy framework to effectively promote sustainable aviation in the long run.
Critical nodes in transportation networks, such as major transit tunnels and interchange stations, are vital for maintaining system functionality following a disruptive event such as a large earthquake. This project focuses on evaluating the seismic resilience of BART’s Berkeley Hills Tunnel that intersects the Hayward Fault, one of California's most active seismic zones. The Hayward Fault poses a significant risk, with the potential for a magnitude 7+ earthquake that could severely impact the tunnel, potentially disrupting BART service and affecting the broader transit network. This study employs the latest fault displacement hazard data and models to estimate the probability of fault rupture displacements and assesses the resulting damage. It then evaluates the likelihood of service interruptions caused by potential Hayward Fault events. Theresults suggest that the tunnels may experience minor to significant damage depending on the amplitude of the faultdisplacement, which can lead to repair times ranging from a few weeks to over a year. The findings highlight the importance of improving tunnel resilience to minimize service disruptions and ensure efficient recovery following major earthquakes.
As online shopping nears its third decade, it is clear that its impacts on urban goods flow are profound. Increased freight traffic and related negative externalities such as greenhouse gas emissions and local air pollution can impede sustainability goals. In response, e-retailers are exploring innovative distribution strategies to enhance last-mile delivery sustainability and efficiency. They use urban consolidation centers with light-duty vehicles like electric vans and cargo bikes, establish alternative customer pickup points, and deploy crowdsourced delivery networks. Advanced technologies that may streamline deliveries, such as autonomous delivery robots and unmanned aerial vehicles, are being tested. University of California Davis and Irvine researchers have investigated these strategies under economic viability, environmental efficiency, and social equity frameworks. Different modeling approaches were implemented to evaluate last-mile network designs and the potential for decarbonizing delivery fleets by switching to electric vehicles. Key findings suggest that while these innovative strategies offer substantial environmental benefits and reduce operational costs, they also present challenges like higher initial investments and operational hurdles. The study emphasizes the need for ongoing innovation and careful strategy implementation to balance sustainability with urban delivery systems’ economic and service reliability demands.
