policy brief

How Did Transit Service Adjustments During the Pandemic Impact Job Accessibility in the San Francisco Bay Area?

Publication Date

January 1, 2025

Author(s)

Phoebe Ho, Johanna Zmud, Joan Walker

Abstract

This study examined geographic and temporal patterns in service adjustments and evaluated their job accessibility impacts for three major San Francisco Bay Area transit agencies between 2020 and 2023: the Alameda-Contra Costa Transit District (AC Transit), the San Francisco Bay Area Rapid Transit District (BART), and the San Francisco Municipal Transportation Agency (MUNI). This retrospective analysis can help transit agencies develop equitable service strategies in the event of future disruptions.

published journal article

Demand-side challenges and research needs on the road to 100% zero-emission vehicle sales

Abstract

Most net-zero emissions targets require electrification of the entire light-duty vehicle fleet, and before that the electrification of all new vehicle sales. This paper reviews literature on demand-side issues related to achieving 100% zero-emissions vehicle sales, focusing on plug-in electric vehicles (PEVs). It discusses potential demand-side challenges to increasing PEV sales and related research gaps, including consumer factors (perceptions, knowledge, and consumer characterises), demand-focused policy (incentives), infrastructure, and energy prices. While global PEV sales have substantially increased in recent years, several challenges remain: some demographic groups are currently underrepresented among PEV buyers (e.g. renters, lower income buyers), some car drivers are resistant to PEVs, incentives are influential but have predominantly benefited higher-income new-car buyers and are being phased out, infrastructure is not sufficiently developed or equally distributed, infrastructure is not user friendly, and some households lack charging access. Some issues identified may be related to the early stage of the PEV market, though they will need to be addressed to reach higher PEV sales and PEV fleet shares. Finally, it outlines areas where more research is needed to understand and guide the PEV transition.

policy brief

Debt Burden from Automobile Loans Exacerbates Racial Inequality in California’s Communities

Abstract

Automobiles can greatly enhance access to employment and other opportunities. However, many households do not have the resources to purchase a vehicle outright and must rely on automobile loans. This increases the total cost of owning a vehicle, particularly for non-white consumers who may have to pay higher purchase prices and/or higher interest rates due to discriminatory lending practices. The effects of high household debt—of which automobile loans are one component—are magnified in lower income neighborhoods, leaving residents with fewer resources to invest in the local economy. The research team used the University of California Consumer Credit Panel, a dataset from Experian, which tracks every loan and borrower in California, to examine how and why automobile loan debt varies from place to place in the state and its consequences. They specifically tested whether total automobile debt, debt burden (the ratio of automobile debt to income), and automobile loan delinquencies in 2021 disproportionately affected non-white neighborhoods.

policy brief

Assessing the Shift to Remote and Hybrid Work in California throughout the COVID-19 Pandemic

Abstract

Beginning in 2020, many in-person activities were replaced by virtual activities as a response to the COVID-19 pandemic. This affected fundamental elements of transportation systems such as trip frequency, commute distance, origins, and destinations. For example, remote work and study were widely adopted among workers and students. Still, the ways that the pandemic affected individuals’ work arrangements across different phases of the pandemic and the extent to which full remote work and hybrid work induced by the pandemic might persist in the future are unclear. In addition, recent studies are not conclusive regarding the ways changes in work arrangements do/will impact travel patterns and trip making.

policy brief

What Matters Most to Drayage Companies When Considering a Zero-Emission Truck: Insights from Small and Large Fleet Operators

Abstract

Drayage trucks (i.e., heavy-duty trucks that move containers and bulk freight between ports and rail facilities, distribution centers, and other nearby locations) are a critical part of port operations, however, they also adversely affect air quality. In California, drayage fleets are facing strict regulatory pressure under the Advanced Clean Fleets (ACF) regulations. Starting in January 2024, all newly registered drayage trucks in the CARB Online System must be zero emission vehicles (ZEVs), so either a battery electric truck (BET) or hydrogen fuel cell electric truck (HFCET). By 2035, every drayage truck operating in California must be zero-emission.
To successfully meet this policy goal, it is important to understand the viewpoints of drayage fleet operators. However, there is limited knowledge about how fleets of various sizes, especially small fleets with 20 or fewer vehicles (which make up 70% of the sector), are responding to ZEVs and related policies. To bridge this gap, the study team surveyed both small and large drayage fleet operators at the Ports of Los Angeles and Long Beach, with 71 companies participating. As part of the survey, fleet operators were asked to choose a preferred truck under different scenarios. In the first scenario, they chose between different ZEV trucks; in the second scenario, they chose between ZEVs, diesel, or natural gas trucks, shedding light on potential reasons which fleets might delay ZEV adoption if they still prefer diesel or natural gas trucks. The team analyzed around 650 choice observations using statistical models to explore these preferences, as well as other survey items regarding their perceptions.

policy brief

On-Road Motor Vehicles No Longer Dominate Ozone Formation

Abstract

The amount of traffic on California’s roadways decreased by approximately fifty percent during the COVID-19 pandemic lockdown in March and April of 2020. Conventional wisdom led to the expectation that reduced traffic would result in reduced ozone (O3) concentrations—ozone being a main component of smog—yet ozone concentrations increased during this period. Internal combustion vehicles emit oxides of nitrogen (NOx) and volatile organic compounds (VOCs). These emissions are precursors for ozone formation, but the relationship between these precursor emissions and the final ozone concentration is complex. The ratio of NOx/VOCs determines if the ozone formation will be “NOx-limited” or “NOx-rich”. Major NOx reductions are required to reduce ozone concentrations when the atmosphere is NOx-rich. Small NOx reductions in a NOx-rich atmosphere can actually increase ozone concentrations.

To inform ongoing efforts to reduce ambient O3 concentrations, this brief highlights findings from research that collected and analyzed air pollution measurements in urban locations adjacent to major freeways in the City of Sacramento and the City of Redlands—both during and after COVID-19 stay-at-home orders. The results provide an updated estimate for how many more years of NOx control will be required before O3 benefits are realized.

published journal article

Connected Automated Vehicle Impacts in Southern California Part-I: Travel Behavior and Demand Analysis

Abstract

Connected and automated vehicle (CAV) technologies attracted extensive attention in the past decade. As CAV brings convenience to travel, people’s travel behaviors and patterns might change significantly. Existing models, however, cannot comprehensively evaluate the impacts on transportation systems. This study adopted an activity-based approach to evaluate the comprehensive CAV impacts on the transportation system in Southern California. A stated preference survey was conducted and captured people’s behavior changes associated with CAV deployment. The model prediction demonstrated that the total trip number increased by 9%, with a 13% growth in total car-like mode travel distance. Among all trip purposes, work trips contributed to 49% of total trip number growth and 75% of the increased car-like mode travel distance. The advanced CAV technology alone wouldn’t directly benefit future transportation systems and it is still critical to have appropriate policy interventions in place.

published journal article

Does Discretion Delay Development?

Abstract

Problem, research strategy, and findings:
Local governments sometimes approve multifamily housing through a discretionary process, meaning a public body must vote to entitle the proposal before it can seek a building permit. By-right entitlement, in contrast, allows developers to apply directly for a building permit. We tested the hypothesis that by-right approvals are faster. Faster approval can make multifamily development more feasible, which can in turn improve housing affordability. Analyses of approval pathways are often confounded by project size and complexity, but we exploited a provision in the Los Angeles Transit-Oriented Communities (TOC) program that allowed many large projects to use by-right approval. Using data from roughly 350 multifamily projects permitted in Los Angeles (CA) from January 2018 through March 2020, we compared approval timelines for both by-right and discretionary projects. We found that by-right projects were permitted 28% faster than discretionary projects, controlling for project and neighborhood characteristics. By-right projects also had less variance in their approval times, suggesting that by-right approval offers not just more speed but more certainty.

Takeaway for practice:
Planners should create more opportunities for multifamily housing to be permitted by right. Despite some selection bias in our study, evidence from the TOC program suggests that creating a by-right option would accelerate approval time and thus substantially benefit housing production. The faster approval timelines, moreover, have been accompanied by an increase in average project size and the number of units reserved for low-income households.

policy brief

The Eighty-Five Percent Solution: Is Crowdsourcing Speed Limits the Best Approach to Traffic Safety?

Publication Date

September 1, 2020

Author(s)

Brian D. Taylor, Mark Garrett, Yu Hong Hwang

Abstract

Setting appropriate speeds on roadways requires balancing the economic and social benefits of higher vehicle speeds on one hand, against the greater safety, environmental, and human activity costs of fast-moving traffic on the other. While drivers and commercial shippers typically favor faster limits, those living, walking, biking, or playing in proximity to roads often want slower limits. The most common method for setting speed limits, however, leaves it to drivers to collectively decide how fast is too fast. According to the U.S. Federal Highway Administration (FHWA), most places in North America set speed limits using the “85th-percentile rule.” This long-established standard calls for observing the speeds of free-flowing traffic on a roadway without posted speed limits, and then setting the limit at a 5 mph increment above or below the speed at which 85% of vehicles travel. So, for example, if 85% of drivers on a particular road are observed to travel at 43 mph or less, the speed limit would be set at 45 mph.

published journal article

The Eighty-Five Percent Solution: A Historical Look at Crowdsourcing Speed Limits and the Question of Safety

Abstract

The “85th percentile rule” is commonly used to set speed limits in jurisdictions across the U.S. Modern interpretations of the rule are that it satisfies key conditions needed for safe roadways: it sets speed limits deemed reasonable to the typical, prudent driver, reduces the problematic variance in travel speeds among vehicles, and allows law enforcement to focus on speeding outliers. Authoritative publications regularly assert that the rule came about because early driving surveys often found that drivers moving at or below the 85th percentile of a speed on a given roadway were within one standard deviation of the mean speed for that roadway and were in the low involvement group for traffic incidents. But does this widely used rule for setting speed limits really have such a scientific pedigree? Given debates in cities around the U.S. about competing uses of street space, we examine where this rule of driver-set speed limits actually came from and whether rule developers’ rationales still hold true today. While most observers trace the rule to safety research and a 1964 report, we find that the 85th percentile rule actually emerged decades earlier amidst the nascent traffic engineering profession’s preoccupation with “traffic service” to increase vehicular throughput; and with respect to safety, the rule was explicitly intended as a starting point in speed limit setting, and not the last word.