Transportation Plans: Their Informational Content and Use Patterns in Southern California

Status

Complete

Project Timeline

January 1, 2018 - December 31, 2018

Principal Investigator

Campus(es)

UC Irvine

Project Summary

Since 1937, “all cities and counties [have been] required to adopt master plans [called ‘general plans’ nowadays] … [and, in 1955] land use and circulation elements [became] required in the general plan” (California Governor’s Office of Planning and Research, 2003). Recently, as the California Complete Streets Act (AB 1358) is implemented, “all cities and counties, upon the next update of their circulation element, must plan for the development of multimodal transportation networks.” Other state legislation (e.g., SB 375) has placed emphasis on internal consistency (e.g., consistency of a locality’s circulation element with other general plan elements or policies it has adopted) and cooperation among jurisdictions to achieve regional Greenhouse Gas (GHG) emission reduction targets and other goals set included in the Sustainable Communities Strategy (SCS) and Regional Transportation Plan (RTP). However, despite the state-level guidelines and requirements, general plan making rests with individual localities, and the content/structure of plans does vary markedly across cities. Little is known about the informational contents of these plans and their use patterns. This project reviewed the content of eight recently adopted general plans in Orange County and conducted a plan use survey and follow-up analysis of survey responses. All plans analyzed were found to convey a variety of information about their visions, goals, policies, and implementation strategies, but the plan content analysis revealed substantial variation in the way cities composed their general plans and integrated them with other plans/players. Compared to land use elements, circulation elements tended to focus more on their connections with other agencies than on internal consistency. The plan use survey yielded a low response rate which may indicate limited use of plans in the field. However, a majority of the survey responses were positive about the usefulness and usability of general plans.

Does Bundled Parking Influence Travel Behavior?

Status

Complete

Project Timeline

September 1, 2017

Principal Investigator

Miriam Pinski

Project Team

Campus(es)

UCLA

Project Summary

Parking requirements hide the cost of storing a vehicle in housing costs, making driving a more attractive option for vehicle owners than using alternative modes of transportation.This study uses data from the 2013 American Housing Survey to determine if the presence of bundled parking is associated with a household’s transportation mode choice. After controlling for differences in socioeconomic and built environment characteristics, the presence of bundled parking is found to be associated with a 27 percent increase in vehicle miles traveled. Bundled households drive approximately 3,800 miles more, spend nearly $580 more on gasoline, and emit 14.47 more metric tons of carbon dioxide per year. Bundled parking is also negatively correlated to transit use, and households with unbundled parking are significantly more likely to be frequent transit users. This provides further evidence for the already strong case against parking requirements.

Efficient Mobility Portfolio Schemes for Integrated, Intermodal, and Incentivized Shared Transportation

Status

In Progress

Project Timeline

January 1, 2018 - December 31, 2018

Principal Investigator

Project Summary

Flexible transportation options such as ridesharing, carsharing, and bikesharing can be effective feeders for public transportation service because these new options have higher accessibility to travelers’ origin and destination. The private sector that now plays an increasing role as a component of urban transportation can augment public transportation accessibility. In other words, Transportation Network Companies (TNCs) and Mobility Service Providers (MSPs) can be complementary modes to transit system by providing shared use of transportation capacity. This option requires a matching algorithm between drivers and riders. Implementing a comprehensive multi-modal multiple-option shared travel system in an urban area is required to improve efficiency of transportation systems. This integrated platform can identify various travel options and recommends travelers with tailored information. Some options might have a route consisting of multiple modes (i.e.: ridesharing- transit-bikesharing). Some options might suggest a detour, compared to the shortest path what user’s primary mode has. To compensate the loss of users’ utility by giving up their primary mode and to encourage use of alternative mode option, the optimal incentive scheme will be proposed. This proposal is to study the benefits of a smart mobility portfolio which is a trip planning system integrating multiple travel modes and including an incentive scheme. A smart mobility portfolio can provide time-dependent trip plans across multiple modes that include several options such as shared-cars, shared-rides, bikesharing, bus/rail transit and combinations of travel modes. Four main components of this system are: 1) to identify travel options for achieving efficiency under current traffic conditions and supply conditions, 2) to calculate proper amounts of incentive to attract people to choose one of the options, 3) to provide travelers with the best travel options among these alternatives, and 4) to examine the impact of the proposed method to entire transportation systems and to update the parameters in the model. Encouraging people to change their current travel behavior through the smart mobility portfolio platform, researchers expect the improvement of traffic network efficiencies and the contribution to eco-friendly environment by reducing traffic congestion.

Simulating Life with Personally-Owned Autonomous Vehicles through a Naturalistic Experiment with Personal Drivers

Status

Complete

Project Timeline

July 1, 2017 - December 31, 2020

Principal Investigator

Project Team

Project Summary

To date, little is known about how travel will change with self-driving vehicles. The biggest difference in using a self-driving car, and arguably the feature that will cause the most change in travel behavior, is not having to be behind the wheel driving the car or having to be in the car at all as it travels from one place to another. Existing behavioral studies exploring this unknown future are limited because they either focus on safety and human factors rather than travel behavior, assume travel behavior implications, or ask about hypothetical scenarios that are unfamiliar to the subjects. This project will explore the potential impacts of self-driving vehicle deployment on travel patterns and behavior through a naturalistic experiment. Households in the greater Sacramento area will be recruited to participate in a three-week travel study. All travel during this time will be monitored and tracked. At the beginning of the three-week period, participants will take part in a one-on-one entrance interview to receive an overview of self-driving cars and share their attitudes toward self-driving cars. During the second week, participants will have access to a professional driver for a set block of time. Having access to a driver will relieve participants from the duty of personally driving or physically being in a car when the car is making trips, while maintaining the other aspects of owning a personal vehicle (e.g. fuel and other vehicle costs). Upon completion of the three-period, participants will take part in an exit survey similar to the entrance survey in terms of (re)asking about attitudes toward self-driving cars in addition to being asked about their experience with the simulated self-driving car experience. This experiment leverages a framework that has already been beta tested providing evidence of value.

Linking Statewide and Regional Travel Models to Estimate Interregional Travel Impacts in California

Status

In Progress

Project Timeline

October 1, 2016 - June 30, 2024

Principal Investigator

Campus(es)

UC Irvine

Project Summary

Metropolitan Planning Organizations (MPOs) use regional travel forecasting models to estimate vehicle trips (VT), average speeds, and vehicle miles traveled (VMT), which serve in turn as input to regional emission models. Interregional travel is not usually part of MPO models, but it is explicitly part of statewide models. The California Statewide Travel Demand Model (CSTDM) is an activity-based model that produces statewide origin-destination trip tables for assignment to the statewide network. Consistency tests, however, suggest that there are significant deviations between link counts from the CSTDM and those from regional models, as measured at defined cordon stations. These trip counts are, by definition, interregional travel – travel that is typically generated within a region but with performance impacts in another region or in areas not formally part of a defined region.

The proposed project seeks to develop and test methods to synchronize the travel forecasting results of the CSTDM with regional travel forecasting models, with the objective of better estimating interregional travel and greenhouse gas emissions in California. Whether trip-, tour-, or activity-based, CSTDM and all current regional models apply conventional trip assignment as the last step in the modeling process. From the perspective of potential policies to address performance impacts, this study will resolve how regions and the state properly account for the relative proportion of interregional travel and the associated travel impacts. The methodological problem is to synchronize the assigned and validated cordon counts produced by regional models with those generated as part of assignment in the CSTDM. Techniques to modify origin-destination trip tables exist but applications above the local area have been rare. The CSTDM trip tables will be updated to reflect the assigned counts at defined MPO cordon stations. At least two methods will be tested using Caltrans’ Performance Measurement System (PeMS) data with CSTDM trip tables and using MPO cordon estimates with CSTDM trips tables. Each method will be evaluated, with one selected for final application based on its consistency across all model levels and data sources.

policy brief

An L.A. Story: The Impact of Housing Costs on Commuting

Abstract

Concerns about the environmental impacts of transportation have made reducing vehicle miles traveled (VMT) a policy priority. One way to decrease VMT is to decrease the length of commuting trips, and to get commuters out of their private vehicles. Although many studies have investigated the determinants of commuting, few have analyzed the linkage between housing costs and commuting.

To address this gap, researchers at UC Irvine developed a model that jointly explains commuting time and distance, and accounts for residential self-selection (i.e., where someone chooses to live), the effect of car ownership, and key land use characteristics around both residences and workplaces. The research focused on Los Angeles County. Census data shows that the average commute time for Los Angeles County residents pre-pandemic was 32.8 minutes, 18.8 percent higher than the national average.

policy brief

Grocery Shopping in California and COVID-19: Transportation, Environmental Justice, and Policy Implications

Abstract

The COVID-19 pandemic upended many aspects of our lives, including how we shop for groceries. As grocery stores scaled back their opening hours and managed access, many shoppers switched to online shopping with home delivery (“e-grocery”) or store pick-up (“click-and-pick”). Few empirical studies published to date have explored how the COVID-19 pandemic changed grocery shopping, the extent to which these changes may last, how the pandemic exacerbated grocery store access inequalities, and how access to groceries in California is intertwined with environmental justice concerns. Moreover, most studies on this topic were based on non-random samples, which can provide quick results in a fast-changing environment but their findings are not generalizable.

This brief explores the effects of changing grocery shopping trends on disadvantaged communities in California. Using data obtained by surveying California members of KnowledgePanel,® the largest and oldest online probability-based panel representative of the U.S. population, the research team explored the frequency of grocery shopping in California and likelihood of it changing after the pandemic; the types of stores Californians shopped in for groceries during the pandemic and who used grocery delivery companies; and how / if environmental justice factors played a role in observed changes in grocery shopping.

published journal article

Peaked Too Soon?: Analyzing the Shifting Patterns of P.M. Peak Period Travel in Southern California

Abstract

Daily vehicle travel collapsed with the onset of the COVID-19 pandemic in early 2020 but largely bounced back by late 2021. The pandemic caused dramatic changes to working, schooling, shopping, and leisure activities, and to the travel associated with them. Several of these changes have, so far, proven enduring. So, while overall vehicle travel had largely returned to pre-pandemic levels by late 2021, the underlying drivers of this travel have likely changed.

This research examines one element of this issue by analyzing whether patterns of daily trip-making shifted temporally between the fall of 2019 and 2021 in the Greater Los Angeles megaregion. The research team used location-based service data to examine vehicle trip originations for each hour of the day at the U.S. census block group level in October 2019 and October 2021. The team observed notable shifts in the timing of post-pandemic PM peak travel, so the researchers examined changes in the ratio of mid-week trips originating in the early afternoon (12–3:59 PM) and the late afternoon/early evening (4–7:59 PM).

The research paper includes a clear shift in the temporal distribution of PM trip-making, with relatively more late PM peak period trip-making prior to the pandemic, and more early PM peak trip-making in 2021. The peak afternoon/evening trip-making hour shifted from 5–5:59 PM to 3–3:59 PM. The researchers also found that afternoon/evening trip-making each year is largely explained by three workplace-area/school-area factors: (1) the number of schoolchildren in a block group (earlier); (2) block groups with large shares of potential remote workers (earlier), and (3) block groups with large shares of low-wage jobs and workers of color (later, except for Black workers in 2021). The team found the earlier shift in PM peak travel between pre- and late-pandemic periods to be explained most by (1) higher shares of potential remote workers and (2) higher shares of low-wage jobs and workers of color. These findings suggest that the rise of working from home has likely led to a shift in PM peak travel earlier in the afternoon when school chauffeuring trips are most common. This is especially true for low-income workers and workers of color.

policy brief

Did COVID-19 Fundamentally Reshape Telecommuting in California?

Abstract

Health concerns and government restrictions during the COVID-19 pandemic caused a sharp increase in telecommuting (i.e., doing paid work at home or possibly an alternate worksite). In addition to reducing vehicle miles traveled (VMT), decreasing energy use, and lowering emissions of air pollutants and greenhouse gases (GHG), telecommuting may offer numerous other co-benefits, including increasing the worker pool, decreasing time and costs associated with travel, improving work-life balance, and decreasing stress. It may also stimulate greater use of non-motorized and active modes of travel (e.g., walking, biking, taking transit). However, telecommuting (especially during the pandemic) may also affect remote workers’ opportunities for promotion and ties with colleagues, health, work-life balance for families with children (childcare and schools did not operate normally during the pandemic), and even work productivity. It may also increase commuting length because telecommuters tend to live in more suburban areas, usually associated with fewer transit options and a higher likelihood of car use. While a large body of literature on telecommuting existed before COVID-191, this research looked at how the frequency of telecommuting changed in California during the pandemic, and how it may evolve. Whereas most previous research relied on non-random samples, the dataset used for this research was collected at the end of May 2021 by Ipsos, which randomly sampled Californian members of KnowledgePanel©, is the largest probability-based online panel in the nation, so the results are generalizable to California’s population. Quantifying changes in telecommuting is important for updating sustainable community strategies created by Metropolitan Transportation Organizations and gauging telecommuting’s likely contribution to meeting California’s GHG reduction targets. Moreover, analyzing telecommuting frequency for different socio-economic groups and occupations should help policymakers understand the long-term impacts of the pandemic on different segments of the labor market.