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Open Access Publications from the University of California
Cover page of Mode Share Changes in California: An Exploratory Analysis of Factors Affecting Decreases in Walking, Biking and Transit Use from 2012 to 2017

Mode Share Changes in California: An Exploratory Analysis of Factors Affecting Decreases in Walking, Biking and Transit Use from 2012 to 2017

(2023)

This study explores the factors associated with observed changes in transportation mode shares over the period from 2012 to 2017 (corresponding with the period between the two most recent household travel surveys conducted in California). In contrast with the goals of the California Department of Transportation and the State Transportation agency, walking, biking, and using transit all decreased during this period, and driving and the use of personal vehicles increased. There are a number of factors typically associated with transportation mode choices, including socio-demographics, attitudes, life stages, land use and infrastructure availability. Further, large scale events may also have an effect on travel trends; for example, the Great Recessionmay have impacted individuals’ ability to own a personal vehicle and therefore increased the use of alternative means of transportation during the years leading up to our survey period. Similarly, the 2013 passage of legislation allowing for non-citizens to obtain a driver’s license in the state of California, may have impacted mode shares over the study period. This paper compares these and other factors impacting mode shares in 2012 and in 2017 to answer part of the question about why we see this decrease in the use of active modes over this period and what types of planning, programs, and policy actions may help to reverse this trend and get California back on track to increase walking, biking and the use of public transit.

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Cover page of Recommended Approach for Use of Cradle-to-Gate Environmental Product Declarations (EPDs) in Procurement of Civil Infrastructure Materials

Recommended Approach for Use of Cradle-to-Gate Environmental Product Declarations (EPDs) in Procurement of Civil Infrastructure Materials

(2023)

Procurement of more environmentally sustainable materials for civil infrastructure can be supported using environmental product declarations (EPDs). An EPD is a standardized label that is a scientifically sound way to communicate the potential environmental impacts and selected resource use and waste production flows from all or part of the life cycle of a product. To be called a Type III EPD, the life cycle assessment (LCA) for products used in civil infrastructure must be performed in accordance with ISO standards and the relevant product category rule (PCR) for the product type. Most EPDs for civil infrastructure materials in North America are “cradle-to-gate”, i.e., they include the impacts from the extraction of raw materials from the earth and end at the point at which the product is ready to leave the gate of the last manufacturing location. The steps leading to publication of an EPD include: 1) Developing the PCR, 2) Developing the LCA for the EPD, 3) Creating the EPD, and 4) Verification and publishing of the EPD. Industry-average, regional-average, product-specific, and facility-specific EPDs—with differing specificity to a particular product—are used for different purposes. EPDs are a source of data for materials impacts for use in assessment of the complete life cycle. They provide information to identify changes in impacts that can be made early in the materials production. They also can be used to help procure lower impact materials. This white paper discusses benefits of using EPDs and makes recommendations for improving their validity. Several areas needing improvement in current use in procurement are identified and recommendations are presented for improving the use of cradle-to-gate EPDs in transport infrastructure construction materials procurement and to provide input to complete life cycle pavement LCA to support decision-making.

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Cover page of MOVES-Matrix 3.0 for High-Performance On-Road Energy and Emission Rate Modeling Applications

MOVES-Matrix 3.0 for High-Performance On-Road Energy and Emission Rate Modeling Applications

(2023)

This white paper summarizes the development of MOVES-Matrix 3.0 based on EPA’s latest MOVES model known as MOVES3 (version 3.0.4). The research team updated the programs to account for changes in data structures and source sub-types and applied the same conceptual design used in MOVES-Matrix 2.0. The review of the MOVES3 and MOVES 2014b databases indicated a finer definition of the regions in terms of the unique combinations of fuel supply regions vs. Inspection/Maintenance (I/M) programs, with 40 fuel scenarios and 87 I/M scenarios in MOVES3 and 22 fuel scenarios and 84 I/M scenarios in MOVES 2014b. The increased number of fuel scenarios is due to the increased number of formulation regions and the one-to-many corresponding relationship between counties vs. fuel formulation regions by year. A total of 122 regions are defined in MOVES3 compared with 109 regions in MOVES 2014b, and the team anticipates at least 10% more running time to generate matrices for MOVES3, given the larger number of regions and the more complicated source type VSP/STP variables.

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Cover page of Pass-Through of Alternative Fuel Policy Incentives: Evidence from Diesel and Biodiesel Markets, the U.S. Renewable Fuel Standard, and Low Carbon Fuel Standards in California and Oregon

Pass-Through of Alternative Fuel Policy Incentives: Evidence from Diesel and Biodiesel Markets, the U.S. Renewable Fuel Standard, and Low Carbon Fuel Standards in California and Oregon

(2022)

Biodiesel and hydrotreated renewable diesel (RD)—or collectively biomass-based diesel (BBD)—have become integral components of compliance with policies aiming to reduce U.S. transportation sector greenhouse gas emissions. Such policies include the U.S. Renewable Fuel Standard (RFS), California’s Low Carbon Fuel Standard (LCFS), and Oregon’s Clean Fuel Program (CFP). These policies, along with a federal Blender’s BBD Tax Credit (BTC), provide financial incentives for BBD. In this white paper, the authors study pass-through of implicit taxes and subsidies, introduced by federal and state policies, to a variety of diesel and soy biodiesel fuel prices in the context of the U.S. diesel sector, focusing on fossil diesel and soy biodiesel. They apply time series methods techniques to estimate how a variety of diesel fuel price spreads across the country and in California and Oregon responds to changes in the implicit taxes placed on petroleum diesel and the implicit subsidies awarded to biodiesel. The results presented in this paper point to some inefficiencies in the RFS, LCFS, and CFP. The primary contribution of this paper was providing the first set of estimates of pass-through of LCFS implicit taxes and subsidies, and doing so for the diesel sector, a critical player in LCFS compliance.

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Cover page of Jobs and Automated Freight Transportation: How Automation Affects the Freight Industry and What to Do About It

Jobs and Automated Freight Transportation: How Automation Affects the Freight Industry and What to Do About It

(2022)

The expansion of automation in the U.S. economy is increasingly tangible and will presumably entail positive and negative impacts that are not yet well understood. In the freight sector, there is uncertainty about how and when automation will impact labor. Beyond this, there are further unknowns about what the impacts will be on such freight subsectors as warehousing, long- and short-haul. It is expected that penetration rates of freight automation will vary across subsectors. In some subsectors, new jobs will be created and/or working conditions will improve. Other subsectors will see declining job quality and/or job losses that require workers to transition to new roles or sectors entirely, when possible. Changes in job opportunities and quality will vary within sectors and subsectors, by region, and/or by firm. This study offers an overview and recommendations in three directions. First, despite the uncertainties and based on past and present examples of automation, it provides some insights about strategies that may help impacted workers within and outside of the heavy freight sector transition. Second, it discusses examples of existing public policies that can support a transition for automation-impacted workers. And third, it provides insights on how different freight subsectors are likely to be impacted by automation.

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Cover page of From LOS to VMT: Repurposing Impact Fee Programs Since Adoption of SB 743

From LOS to VMT: Repurposing Impact Fee Programs Since Adoption of SB 743

(2022)

This white paper assesses how cities are modifying transportation impact fees in response to Senate Bill (SB) 743, adopted in 2013 to orient environmental review of transportation impacts of development projects and plans in California to support sustainable development. SB 743 and its implementing guidelines eliminated “level of service” (LOS) standards for automobile traffic delay as an environmental impact to be addressed under the California Environmental Quality Act (CEQA), recommending instead that localities and other lead agencies responsible for CEQA review analyze, and if possible, mitigate impacts on vehicle miles traveled (VMT) instead. As cities proceed to implement SB 743, some are going further than the minimum required to analyze and mitigate for VMT at the development project level. Instead, they are also pursuing “programmatic” approaches, including altering citywide impact fees imposed on developers, to support more systematic analysis and mitigation than is possible at the project level alone. Based on public documents research and interviews with consultants and planners, this paper identifies three basic approaches that cities are taking to design impact fees in conjunction with their policy approaches for addressing SB 743: first, to design impact fee programs that fund VMT-reducing projects, but without employing a VMT “nexus” (the nexus is the basis for identifying impacts to be addressed by the program); second, to employ a VMT nexus for identifying facilities need and cost allocation; and third, to design a fee program that links to systematic CEQA-reviewed VMT analysis in the General Plan and/or other related CEQA-reviewed city wide policy documents. In this latter approach, cities may or may not design their fee program to fund VMT-reducing projects; indeed, this approach may help facilitate a more traditional, LOS-based fee program. This outcome can happen if a city analyzes VMT systematically for the General Plan, and then adopts a “statement of overriding considerations” under CEQA, which allows for development projects to “tier” off the programmatic environmental review so as to avoid the need for conducting cumulative VMT impacts analysis. This approach may facilitate more systematic integration of VMT and LOS analysis at the citywide level, but it does not support SB 743 goals for supporting VMT-reducing projects and programs.

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Cover page of Workforce Implications of Transitioning to Zero-Emission Buses in Public Transit

Workforce Implications of Transitioning to Zero-Emission Buses in Public Transit

(2022)

This white paper provides educational and policy-driven approaches to sustainable transportation workforce development in the transit sector with a focus on knowledge transfer and training strategies for zero-emission bus technologies. The authors draw from a comprehensive survey of national research, interviews with transit leaders, and case studies to identify the most critical technology transfer gaps in the adoption of zero-emission bus technologies. The paper concludes with strategic transit workforce priorities and related recommendations for transit leaders, educational partners, and policy makers.

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Cover page of The Current and Future Performance and Costs of Battery Electric Trucks: Review of Key Studies and A Detailed Comparison of Their Cost Modeling Scope and Coverage

The Current and Future Performance and Costs of Battery Electric Trucks: Review of Key Studies and A Detailed Comparison of Their Cost Modeling Scope and Coverage

(2022)

This project aims to assess the current and future performance and costs of battery electric trucking, through reviewing key recent studies in the U.S. and presenting a detailed comparison of their cost modeling scope and coverage. This white paper presents a review of 10 recent studies of the total cost of ownership (TCO) of battery electric trucks (BET), now and in the future, compared to a baseline diesel truck, for the following 3 important types of truck: heavy-duty long-haul trucks, medium-duty delivery trucks, and heavy-duty drayage/short-haul trucks. The researchers break down the studies into their estimates for a range of important cost and operating factors, such as vehicle purchase cost, efficiency, fuel cost, maintenance cost, required range and thus battery pack sizing, and other factors. Of note are differences in major assumptions of studies and variables that are included or excluded from consideration. The authors do not judge these studies against each other but attempt to derive general findings that are robust across studies, areas of significant difference, and areas for further research. Overall, TCO estimates across the studies, for a given truck type, can vary dramatically, though often several studies cluster together. But as this study explores, the differences in TCO link directly to differences in assumptions, parameters and other differences across the studies. The studies vary in important ways that should be taken into account when comparing TCO estimates. Policy makers should consider the context of truck type, truck use and other factors when reading such studies, and pay attention to assumptions. Policies should reflect the wide range of situations that trucks may encounter and avoid assuming a simple average TCO across all situations.

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Cover page of Improving the Transfer of Knowledge from Scientists to Policy Makers: Best Practices and New Opportunities to Engage

Improving the Transfer of Knowledge from Scientists to Policy Makers: Best Practices and New Opportunities to Engage

(2022)

Many scientific projects are intended to inform public policy, however there are often difficulties transferring or translating research from scientists to policy makers. This paper reviews the existing literature on the quality of communication between scientists or field experts and policy makers and the challenges they face in conveying their research. A majority of best practice recommendations related to effective communication are rooted in anecdotal evidence and have not yet been subjected to systematic scientific study. This is, in part, because the nature of public policy makes data collection, randomization, or correcting for confounding factors extremely challenging. Studies that do put these recommendations to the test are most commonly fielded as national surveys of field experts and policy makers in comparative contexts. Few studies examine this subject in the United States, however, and most find mixed results as to the efficacy of well-accepted scientific communication strategies. Further, existing work often fails to account for the impact of reputation on the willingness of scientists to engage in policymaking and the willingness of political actors to seek and accept expert input in the policymaking process, unless it confirms pre-existing biases. The authors explain how this gap in the literature has important consequences for the quality of policies produced and suggest future avenues of research in the pursuit of sincere evidence-based policymaking.

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Cover page of Environmental Plans and Freight Movement at the San Pedro Bay Ports: A Quick Strike Analysis

Environmental Plans and Freight Movement at the San Pedro Bay Ports: A Quick Strike Analysis

(2022)

Critical to freight movement in Southern California are environmental plans at the Port of Los Angeles (POLA) and Port of Long Beach (POLB). The combined port complex is the single largest fixed source of air pollution in the South Coast Air Basin. This white paper presents three case studies from the San Pedro Bay Ports Clean Air Action Plan (CAAP), including brief analyses of their effects on freight movement in the region. This research also includes a case study of a private-sector, yet-to-be-built infrastructure project designed to support the faster movement of freight out of the San Pedro Bay Ports called the Southern California International Gateway (SCIG). The case studies are provided to elucidate how self-regulating agreements and operator-led programs contribute to regional environmental goals for freight operations. The findings indicate in part that stakeholder power relationships influence the ability to both develop environmental strategies and determine their outcomes. They also indicate that port-focused plans are more effective when their impact on the entire supply chain is considered. The research also helps to illustrate examples of unintended consequences of freight-related environmental measures which will prove useful to policymakers and operators alike.

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