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Sponsor: SB1

Telework Trends in California: Before, During, and Possibly After the Pandemic

Status

Complete

Project Timeline

April 1, 2022 - June 30, 2023

Principal Investigator

Jean-Daniel Saphores

Project Team

Md Rabiul Islam, Monica Ramirez-Ibarra

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2022-43
(Also see the UC ITS page)

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

Team Departmental Affiliation

Civil and Environmental Engineering

Project Summary

Forced by the COVID-19 pandemic and enabled by technology improvements, telework has received a big boost over the past 15 months. In addition to reducing vehicle miles traveled (VMT), decreasing energy use, and lowering emissions of both air pollutants and of greenhouse gases, telecommuting has numerous potential co-benefits, including saving time (from commuting) and money (on gas and parking), increasing schedule flexibility, potentially improving work-life balance, and reducing stress (Gajendran and Harrison, 2007). To understand the extent to which telecommuting could increase because of the pandemic, this project will analyze a unique dataset on commuting and telework collected during a May-June 2021 random survey of Californians conducted by IPSOS. In addition, the research will quantify changes in VMT and in the resulting emissions of air pollutants and greenhouse gases. Quantifying recent changes in telecommuting is important to update sustainable community strategies and for understanding the likely contribution of telecommuting in meeting California’s GHG reduction targets.

Related Publications

published journal article | Feb 2025

WILL COVID-19 jump-start telecommuting? Evidence from California
Transportation

Read more
policy brief | Aug 2024

Did COVID-19 Fundamentally Reshape Telecommuting in California?

Read more

Development of New Privacy-preserving Method for Traffic Data Collection and Analysis

Status

Complete

Project Timeline

August 1, 2021 - September 30, 2023

Principal Investigator

Wenlong Jin

Project Team

Jooneui Hong

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2022-45
(Also see the UC ITS page)

Areas of Expertise

Other

Team Departmental Affiliation

Civil and Environmental Engineering

Project Summary

Traditional methods for data collection, such as the National Household Travel Survey, focus on trips by a small sample of either travelers, locations, or times. With the prevalence of GPS devices and smartphones, big transportation data from more travelers and locations over longer timespans are more readily available and can substantially help to improve the management, planning, and design of transportation systems. However, travelers, private companies, and public agencies are reluctant to share such data due to privacy concerns. This project will develop a new privacy-preserving method for collecting and analyzing traffic data. This method is based on a new framework for transportation system analysis, in which a network is considered a single entity, and trips are tracked in a relative space with respect to the remaining distance to individual travelers’ destinations. Such data are sufficient for characterizing traffic dynamics but without revealing Personally Identifiable Location Information. This method works for either a city road network or freeway corridors, as well as for multimodal trips. The project will systematically calibrate and validate the new method and will discuss the policy implications for data collection and analysis for California’s traffic systems.

Related Publications

policy brief | Jan 2025

Using a “Bathtub Model” to Analyze Travel Can Protect Privacy While Providing Valuable Insights

Read more
research report | Feb 2026

Development of New Privacy-preserving Method for Traffic Data Collection and Analysis: The Bathtub Model Approach

Read more
Preprint Journal Article | Sep 2023

Priority Queue Formulation of Agent-Based Bathtub Model for Network Trip Flows in the Relative Space

Read more

Analyzing Telecommuting and Travel in California Before, During, and After the Pandemic

Status

Complete

Project Timeline

April 1, 2022 - June 30, 2024

Principal Investigator

Michael McNally

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2022-47
(Also see the UC ITS page)

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

Team Departmental Affiliation

Civil and Environmental Engineering

Project Summary

The COVID-19 pandemic has disrupted day-to-day business and triggered massive changes in travel behavior for work and other activities. Due to social distance and travel restrictions imposed during the pandemic, teleworking has become much more prominent: a survey estimated that between February and May 2020, over one-third of the American labor force switched from in-person work to telework. The Census Pulse Survey (2020-2021) reported that 40% of households in California indicated that at least one household member substituted in-person work with telework (compared to the US national average of 37%). The pandemic provides a unique opportunity to examine the potential impacts of teleworking on travel and measure the potential effectiveness of this work arrangement as a travel demand and environmental management tool. This study examines changes in telecommuting and the resulting activity-travel behavior during the COVID-19 pandemic, with a particular focus on California. A geographical approach was taken to “zoom in” to the county level and to major regions in California and to “zoom out” to comparable states (New York, Texas, Florida). Nearly one-third of the domestic workforce worked from home during the pandemic, a rate almost six times higher than the pre-pandemic level. At least one member from 35 percent of U.S. households replaced in-person work with telework; these individuals tended to belong to higher income, White, and Asian households. Workplace visits have continued to remain below pre-pandemic levels, but visits to non-work locations initially declined but gradually increased over the first nine months of the pandemic. During this period, the total number of trips in all distance categories except long-distance travel decreased considerably. Among the selected states, California experienced a higher reduction in both work and non-workplace visits and the State’s urban counties had higher reductions in workplace visits than rural counties. The findings of this study provide insights to improve understanding of the impact of telecommuting on travel behavior during the pandemic.

Related Publications

book/book chapter | Jan 2023

Impacts of the COVID-19 Pandemic on Telecommuting and Travel

Read more

Between the Forest and the Trees: Community Strategies to Transform Roadways in California’s San Joaquin Valley

Status

Complete

Project Timeline

October 1, 2022 - June 30, 2024

Principal Investigator

Doug Houston

Project Team

Gregg Macey

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2023-38
(Also see the UC ITS page)

Areas of Expertise

Safety, Public Health, & Mobility Justice Travel Behavior, Land Use, & the Built Environment

Team Departmental Affiliation

Urban Planning and Public Policy

Project Summary

Expanding participation of historically disenfranchised groups within decision-making processes is an important strategy to increase equity within transportation planning but traditional engagement practices (e.g., public meetings, focus groups) have historically done little to address the needs of disadvantaged communities. This study evaluates the opportunities and barriers to using a community steering committee participation model within transportation planning to advance equity and environmental justice. It utilizes interview and case study analysis to examine the experiences of residents and community leaders in prioritizing community-identified strategies to mitigate roadway hazards in three AB 617 communities in California’s San Joaquin Valley – Stockton, South Central Fresno, and Arvin/Lamont. It investigates the role resident and CBO members played in the prioritization, approval, and implementation of three strategies to transform roadways and mitigate air pollution, noise, dust, and safety hazards: (1) new vegetative barriers between major roadways and sensitive land uses; (2) expanded sidewalk infrastructure; and (3) revised heavy-duty truck route designations. Findings demonstrate that “meaningful involvement” for impacted communities within transportation planning will require officials, residents, and organizations to commit to an ongoing process of experimentation and learning about the most effective approaches for advancing transportation equity and environmental justice.

Related Publications

policy brief | Aug 2025

Advancing Community-Identified Strategies to Transform Roadways in California’s San Joaquin Valley

Read more
research report | Aug 2025

Between the Forest and the Trees: Community Strategies to Transform Roadways in California’s San Joaquin Valley

Read more

Evaluating the Travel Behavior Impacts of Los Angeles Metro’s K-14 Fareless Initiative

Status

Complete

Project Timeline

October 1, 2022 - June 30, 2024

Principal Investigator

David Brownstone

Project Team

Henry Bernal

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2023-37
(Also see the UC ITS page)

Areas of Expertise

Public Transit, Shared Mobility, & Active Transportation Travel Behavior, Land Use, & the Built Environment

Team Departmental Affiliation

Economics

Project Summary

In October 2021, the Los Angeles County Metropolitan Transportation, or LA Metro (the largest transit agency in Los Angeles County), launched the GoPass Fareless pilot program in collaboration with other regional transit operators and multiple school districts across the county. The program offers free transit passes to K-14 students. Students attending eligible schools may enroll in the program by receiving a card from their school and registering it online. Participation in the program is decided by school districts, who opt in by paying a cost-sharing fee of $3 per student per year. While other student fareless programs have been attempted and some others remain in service—including the DASH to Class program which offers free rides on the City of Los Angeles’s DASH service and has been active since 2019—the scale of LA Metro’s program provides a unique opportunity to assess the ability of a large-scale program to change travel behavior among participating students. This project will 1) analyze the differences in student enrollment in the GoPass fareless program among eligible schools based on socio-economic characteristics and access to existing transit services; 2) assess how the program has impacted ridership at Metro-operated bus stops near schools in the weekday morning and afternoon peak hours; and 3) identify individual characteristics that influence students’ trip generation and mode choices for school and other trips. The project will survey Los Angeles United School District (LAUSD) high school students about their current school, work, extracurricular travel activities, and availability of household mobility devices compared to their travel behavior before joining the program.

Related Publications

research report | Mar 2026

Impacts of LA Metro’s K-14 Fareless Transit Initiative on Youth Travel Behavior

Read more

Teleworking, Travel, and Quality of Life Before, During, and After the Pandemic Across Different Population Groups in the U.S.

Status

Complete

Project Timeline

October 1, 2022 - June 30, 2024

Principal Investigator

Michael McNally

Project Team

Rezwana Rafiq

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2023-41
(Also see the UC ITS page)

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

Team Departmental Affiliation

Civil and Environmental Engineering

Project Summary

The COVID-19 pandemic and the imposed social distancing measures led many people to adopt telecommuting arrangements — working from home or teleworking — on a large scale. A recent survey found that, between February and May 2020, over one-third of the American labor force swapped in-person work with telework, which increased the share of remote working to nearly 50 percent of the nation’s workforce. These massive changes in work arrangements may have long-term impacts, including how work is organized, where work is performed, and how activities and travel are scheduled. If telecommuting continues it is important to know whether it results in less travel, less commute stress, and consequently a happier life. This study explores the impact of the COVID-19 pandemic on telecommuting (working from home) and travel during the first year of the pandemic in the United States (from March 2020 to March 2021), with a particular focus on examining the variation in impact across different geographies. The 50 U.S. states are divided into several clusters based on their geographic and telecommuting characteristics, including 6 small urban states, 8 large urban states, 18 urban–rural mixed states, and 17 rural states. Combining data from multiple sources, this study finds that nearly one-third of the U.S. workforce worked from home during the pandemic, which was six times higher than the pre-pandemic period, and that these fractions varied across the clusters. More people worked from home in urban states compared with rural states. As well as telecommuting, several activity travel trends were also examined across these clusters: reduction in the number of activity visits; changes in the number of trips and vehicle-miles traveled; and mode usage. Findings show there was a greater reduction in the number of workplace and nonworkplace visits in urban states compared with rural states. The number of trips in all distance categories decreased except for long-distance trips, which increased during the summer and fall of 2020. The changes in overall mode usage frequency were similar across urban and rural states with a large drop in ride-hailing and transit use.

Related Publications

published journal article | Apr 2023

Telecommuting and Travel during COVID-19: An Exploratory Analysis across Different Population Geographies in the U.S.A.
Transportation Research Record: Journal of the Transportation Research Board

Read more
policy brief | Jun 2026

Understanding the Impacts of Telecommuting on Travel Behavior Before, During, and After the Pandemic

Read more

Examining Spatial Disparities in Access to Electric Vehicle Charging Stations in Southern California

Status

Complete

Project Timeline

October 1, 2022 - August 31, 2024

Principal Investigator

Avipsa Roy

Project Team

Mankin Law, Dewei Xiao

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2023-43
(Also see the UC ITS page)

Areas of Expertise

Safety, Public Health, & Mobility Justice Zero-Emission Vehicles & Low-Carbon Fuels

Project Summary

There are significant hurdles to the widespread adoption of electric vehicles (EVs) in the United States ranging from the high cost of EVs to the inequitable placement of EV charging stations (EVCS). A deeper understanding of the underlying complex interactions of social, economic, and demographic factors which may lead to such emerging disparities in EVCS placements is necessary to mitigate accessibility issues and improve EV usage among people of all ages and abilities. This project developed a machine learning framework to examine spatial disparities in EVCS placements using a predictive approach. As a first step, the research team identified the socioeconomic factors that may contribute to spatial disparities in EVCS access. Second, they used these factors along with ground truth data from existing EVCS placements to predict future ECVS density at multiple spatial scales using machine learning algorithms and compared their predictive accuracy to identify the most optimal spatial resolution for the predictions. Finally, the research team compared the most accurately predicted EVCS placement density with a spatial inequity indicator to quantify how equitably these placements would be for Orange County, California. The findings from this study highlight a generalizable framework to quantify inequities in EVCS placements that will enable policymakers to identify underserved communities and facilitate targeted infrastructure investments for widespread EV usage and adoption for all.

Related Publications

presentation | Mar 2023

Spatial Equity of Electric Vehicle Charging Station Placements in Orange County, CA

Read more
conference paper | Jan 2023

Spatial Equity of Electric Vehicle Charging Station Placements in Orange County, CA
102nd Transportation Research Board Annual Meeting 2023

Read more
published journal article | Aug 2022

Examining spatial disparities in electric vehicle charging station placements using machine learning
Sustainable Cities and Society

Read more
other | Aug 2023

Story Map: Examining Spatial Disparities in Electric Vehicle Charging Station Placements Using Machine Learning

Read more

Evaluating the Labor, Environmental, and Safety Implications of Home Delivery Services and Ride-hailing Companies

Status

Complete

Project Timeline

September 1, 2020 - December 31, 2024

Principal Investigator

Amelia Regan

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2021-42
(Also see the UC ITS page)

Areas of Expertise

Freight, Logistics, & Supply Chain Public Transit, Shared Mobility, & Active Transportation

Team Departmental Affiliation

Computer Science

Project Summary

This research will investigate concerns about the negative externalities of home-delivery and ride-hauling operations, including their impacts on safety, the environment, and labor security, by analyzing gig economy industries post-COVID-19. Many of these companies have been hemorrhaging cash since they began operations, and some will surely fold in the next few months (Lyft is not expected to continue much longer, Uber is buying Grubhub, many scooter and e-bike sharing operations will cease to operate). California law AB5 went into effect on January 1, 2020. That law changes how gig economy workers are paid, as well as the sort of benefits they are entitled to. Recent estimates suggest that Uber and Lyft could be liable for hundreds of millions of dollars in back payments to the state of California for unpaid unemployment insurance as a result of AB5. This survey of both the recent academic literature and popular press articles will be complemented with two surveys of Transportation Network Company (Uber, Lyft), Courier Network Services (Doordash, Instacart), and non-employee delivery services (Amazon, Walmart) workers in California, and will complement the recent, but now outdated, extensive study performed by other University of California researchers (Shaheen et al., 2019). This study is not intended to be as comprehensive as that one -- it will focus on ethical concerns related to these industries and changes brought about by the pandemic.

Related Publications

book/book chapter | Jan 2023

Workers and the Post-COVID Transportation Gig Economy

Read more

Investigating Opportunities to Mobilize Community Associations to Promote Sustainable Transportation and Land Use

Status

Complete

Project Timeline

September 25, 2023 - January 31, 2025

Principal Investigator

Jae Hong Kim

Project Team

Idil Tanrisever

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2024-35
(Also see the UC ITS page)

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

Team Departmental Affiliation

Urban Planning and Public Policy

Project Summary

In recent decades, common-interest housing developments have become prevalent in many American cities. According to the Community Associations Institute's 2021 estimates, nearly 30% of the U.S. population now lives in a development or area governed by a community association, with homeowners associations being the most common type. Despite the widespread presence of homeowners associations (HOAs), there has been limited research on how they impact the adoption of new mobility technologies, innovative urban neighborhood designs, and sustainable land use and transportation initiatives. HOAs and similar community governing bodies have the authority to impose additional restrictions on community activities, which has often led to them being perceived as obstacles to achieving a more environmentally friendly and inclusive future. While this perception is grounded in reality, it doesn't fully account for the significant variation in how HOAs operate. This perspective also hinders innovative thinking about how HOAs could contribute to creating more sustainable communities. Exploring ways to engage these influential entities in pursuing various planning objectives is crucial. This project will improve the collective understanding of how HOAs and other community associations impact sustainable land use and transportation. The researchers will achieve this by: i) creating an integrated geospatial database that includes information about HOAs, land uses (including Accessory Dwelling Units, or ADUs), and transportation indicators, ii) investigating the relationship between the presence or absence of HOAs and factors such as ADU construction, travel patterns, and the built environment, and iii) identifying best practices and extracting lessons from successful cases.

Related Publications

presentation | Feb 2025

Multilayered governance and infill development: Mobilizing community associations to promote sustainable land use and transport

Read more

Maximizing the Air Quality and Public Health Benefits of Zero-Emission Off-Road Equipment in Disadvantaged Communities

Status

Complete

Project Timeline

September 25, 2023 - February 28, 2025

Principal Investigator

Scott Samuelsen

Project Team

Michael Mackinnon, Shupeng Zhu, Kai Wu, Kate Forrest

Sponsor, Program & Award Number

SB1 // STRP Faculty Research: 2024-38
(Also see the UC ITS page)

Areas of Expertise

Zero-Emission Vehicles & Low-Carbon Fuels

Team Departmental Affiliation

Mechanical and Aerospace Engineering

Project Summary

Air pollution from off-road sources disproportionately affects socially and economically disadvantaged communities, particularly low-income and minority populations, often due to historical discrimination that led to their close proximity to such activities. As part of California's climate objectives, there is a focus on deploying zero-emission (ZE) battery electric and hydrogen fuel cell equipment, which can significantly reduce air pollution. However, there are aspects of this transition that need to be better understood in order to maximize benefits for vulnerable communities. For instance, pinpointing high-impact industries that stand to gain the most from this transition will aid in developing policies and strategies that prioritize deployment in these sectors and locations. Additionally, evaluating these benefits necessitates the use of advanced air quality modeling tools that consider both primary emissions and secondary pollutant formation.This project will comprehensively assess the air pollution health benefits of ZE off-road equipment in California with the goal to better understand how these benefits can be maximized in disadvantaged communities through incentives and other policy mechanisms. The study consists of four key steps. First, the researchers will analyze how ZE off-road equipment affects air quality by looking at where and when pollutants like NOx and particulate matter (PM) are released and use the PATHWAYS model to compare emissions outcomes when traditional combustion equipment is used versus ZE off-road equipment. Second, the project will examine how different emissions outcomes impact air pollution levels, including ground-level concentrations of ozone and PM. Third, the researchers will assess health-related impacts using a mapping and analysis program that can estimate the number of health issues avoided, and fourth, the project will analyze the results using an environmental justice framework to evaluate the potential advantages of ZE off-road equipment in disadvantaged communities.

Related Publications

research report | Jan 2025

Maximizing the Air Quality and Environmental Justice Benefits of Zero Emission Off-road Vehicles and Equipment in California

Read more
policy brief | Jan 2025

Switching to Zero Emission Off-Road Vehicles and Equipment Has Significant Air Quality and Environmental Justice Benefits in California

Read more

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