From Traffic Impact Analysis to Accessibility Impact Analysis: Developing and Testing a Post-LOS, Post-VMT Development Impact Analysis Tool

For decades evaluation of the benefits and costs of new- or re- development in urban areas has centered on the effects of development on nearby traffic flows. Historically, and in most states outside of California, the level-of-service (LOS) scale has been used to approve or disapprove commercial developments. The logic of such an evaluation model is that smooth traffic flows are a primary goal of urban areas, which has the effect of discouraging the sorts of densely developed places that are more easily accessed by foot, bike, shared mobility, and public transit. To overcome the traffic flow focus of traffic impact analyses, the California legislature passed SB 743 in 2013, which mandated a change in the way that transportation impacts are analyzed under CEQA. New CEQA Guidelines were created to replace LOS with a new focus on how proposed developments affect vehicle miles of travel (VMT). This translational project will build on prior research, as well as the burgeoning literature on operationalizing access into transportation planning and engineering to develop and test some new analytical tools to evaluate the access impacts of developments.

By |2024-12-26T23:06:25-08:00December 26th, 2024|
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Sources of and Gaps in Data for Understanding Public Transit Ridership

This project presents and reviews the available sources of data on public transit riders and ridership, as a resource for those who manage or simply wish to understand U.S. transit. In conducting this review, the researchers consider the advantages and disadvantages of publicly available data on transit from a variety of public and private sources, as well the relatively scarcer and less available sources of data on other providers of shared mobility, like ride-hail services, that compete with and complement public transit and pieces missing from the transit analytics pie. Data gaps both align with existing inequities and enable them to continue, unmeasured, as the COVID-19 pandemic has made closing these gaps all the more important.

By |2024-12-26T23:06:24-08:00December 26th, 2024|
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Letting drivers choose how fast to drive: Analyzing the strengths and weaknesses of the 85th percentile rule

Over 3,500 people have died on California’s streets and highways each year since 2016, despite commitments at the state, regional, and local levels to reduce this toll. A growing number of safety experts have pointed to high speed limits as a serious obstacle to increased traffic safety. The basic rule for setting motor vehicle speed limits in California, and across the U.S. is the “85th Percentile Rule.” This rule is deeply ingrained, both practically and legally in transportation engineering practice, but is now being scrutinized by those committed to improving traffic safety. This research synthesis will review the history and evolution of the 85th percentile rule in traffic engineering practice, and critically analyze and summarize research to date on its effects.

By |2024-12-26T23:06:25-08:00December 26th, 2024|
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Roads, Density and Prices: A Translational Project

In California, driving is cheap and housing is expensive, and both these facts impede the state’s progress toward sustainability, safety and affordability. Efforts to solve these problems, however, often operate on parallel tracks: bold plans to increase housing production say little about congestion, and plans to address congestion rarely discuss the housing crisis. While these omissions are often understandable, they create a situation where policy proposals to solve one problem often flounder on concerns about the other one. Proposals to allow more development, even near transit, encounter resistance from neighbors concerned that development will bring congestion. Similarly, proposals to price roads encounter resistance based on the concern that California is already extremely expensive, and people have to live far from where they work because of the housing crisis. Somehow this policy gridlock must be resolved, if California will meet its stated goals of reducing VMT, reducing emissions, and building millions of units of housing.

By |2024-12-26T23:06:25-08:00December 26th, 2024|
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Transit Blues in the Golden State

From 2014 to 2018, California lost more than 165 million annual boardings, a drop of over 11%. This project examines public transit in California in the 2010s and the factors behind its falling ridership. Transit ridership has been on a longer-term decline in regions like Greater Los Angeles and on buses, while ridership losses in the Bay Area are more recent. While overall transit boardings across the state are down since 2014, worrisome underlying trends date back earlier as patronage failed to keep up with population growth. But reduced transit service is not responsible for ridership losses, as falling transit ridership occurred at the same time as operators instead increased their levels of transit service. What factors help to explain losses in transit ridership? Increased access to automobiles explains much, if not most, of declining transit use. Private vehicle access has increased significantly in California and, outside of the Bay Area, is likely the biggest single cause of falling transit ridership. Additionally, new ride-hail services such as Lyft and Uber allow travelers to purchase automobility one trip at a time and likely serve as a substitute for at least some transit trips. Finally, neighborhoods are changing in ways that do not bode well for public transit. Households are increasingly locating in outlying areas where they experience longer commutes and less transit access to employment. At the same time, a smaller share of high-propensity transit users now live in the state’s most transit-friendly neighborhoods.

By |2024-12-26T23:06:26-08:00December 26th, 2024|
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Street Network Geometry Projects – Global and California

Street rights-of-way are typically a city’s most valuable asset. Streets serve numerous functions — access, movement, and the provision of space for on-street parking, children’s play, and social interaction. But the more land that is devoted to streets, the less land there is available for housing, parks, offices, and other land uses. In this research project, UCLA researchers quantified the width of streets in 20 of the largest counties in the United States, and the value of the land under those streets. This research found that streets in the U.S. are much wider than in other countries. Street widths are normally dictated by subdivision codes and local street design manuals. The highest street land values are found in coastal California, and streets could be much narrower.

By |2024-12-26T23:06:24-08:00December 26th, 2024|
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Transportation Sales Taxes in Los Angeles: Lessons from Forty Years of Experience

This is the second study of voter-approved transportation sales taxes in Los Angeles County performed by the UCLA Institute of Transportation Studies with support from the Haynes Foundation. The earlier study examined the history of the four half cent sales taxes enacted by voters in Los Angeles County between 1980 and 2016. The current study looked in depth at four issues raised but not addressed in the first one. We report on the extent to which the “local return” provisions of the four measures fund transportation programs and projects in the cities and unincorporated areas of the county. We also explored tradeoffs between accountability to the voters through audits and taxpayer advisory committees in comparison with the county’s flexibility to change program elements through amendments when conditions change. Accountability to the voters was enhanced in the later sales tax measures but amendment procedures have been used to respond to changing needs in the county. We examined lawsuits brought against Metro regarding implementation of the sales taxes and found that there have been rather few. The COVID-19 pandemic struck while the study was underway and in response the report also explores the impacts of the pandemic on transportation sales tax revenues and program expenditures. The transportation sales taxes through the end of year 2020 have been the most important and resilient LA Metro funding sources during the pandemic. Sales tax revenue declined but far less than did federal and state sources of finance and revenues from fares paid by passengers.

By |2024-12-26T23:06:24-08:00December 26th, 2024|
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Transportation, Quality of Life, and Older Adults

California is growing faster and aging more rapidly than America as a whole. California’s population aged 60 years and over is expected to grow more than three times as fast as the total population. Older adults age in place – increasingly in suburban areas where access to transit and pedestrian-friendly neighborhoods is limited. Data from the 2017 National Household Travel Survey show that people over age 65 made 86% of their trips by automobile; 66% as drivers. As they age, however, many older adults limit their driving and ultimately lose the ability to drive altogether, affecting their quality of life in old age. This study explores relationships between aging, travel, mobility and residential relocation using a unique longitudinal database rarely before used in transportation research, the Health and Retirement Survey, augmented by other measures, such as transit accessibility.

By |2024-12-26T23:06:25-08:00December 26th, 2024|
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Advancing the Vulnerability Characterization of California Roadways to Wildfires

Wildfires and post-fire debris flows have had severe impacts on California’s transportation system recently, and climate forecasts show that these hazards are likely to become more of a concern in the future. Yet our understanding of the vulnerability of transportation systems to wildfires is in its nascent stages, with focus largely on evacuation logistics and characterizing where risks of fire are increasing and which infrastructure are co-located. Wildfire risk is much more complex as post-fire precipitation events create conditions where roadway stormwater management is failed often leaving remote communities disconnected. There is an opportunity to improve our understanding of the vulnerability of transportation systems and associated adaptation strategies to ensure that services continue to be delivered in the face of growing hazards. This problem is not specific to California as wildfires across the Southwest are becoming more problematic.

By |2024-12-26T23:06:25-08:00December 26th, 2024|
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