Information about pedestrian infrastructure and volume is indispensable to monitoring, evaluating, and improving the environment for comfortable and safe walking. However, determining and organizing the various types of data in a way that is easy to update and analyze can present challenges. This study designed and developed a relational database for pedestrian infrastructure and volume, and comprises two core components (node table and approach table) and several sub-components (tables for crosswalks, sidewalks, buffers, signs, transits, bikeways, bicycle parking, and volumes). Important...
California was the first state to legislate a Safe Routes to School (SR2S) program under Assembly Bill AB 1475 (1999). SR2S funds construction projects that make it safer for children to walk/bicycle to school and encourage a greater number of children to choose these modes of travel for the school commute. The main goal of this project was to assess the long-term impact of program-funded engineering modifications on walking/bicycling levels and on safety. Evaluation of improvements was determined using a targeted method of determining the countermeasures to result in safety and mode shift...
To manage events associated with highways, data systems have been developed to store relevant event information. To reap the full benefits of geographic information system technologies, the relative locations can be integrated into a linear referencing system. The objective of this paper is to present a methodology for building a highway linear referencing system by applying preexisting marker measurements to a digital street network. The system was developed for locating motor vehicle collisions in California and resulted in improved accuracy compared to a previously developed system....
Safety interventions (e.g. median barriers, photo enforcement) and road features (e.g. median type and width) can influence crash severities, crash frequencies, or both. Both dimensions—crash frequency and crash severity—are needed to obtain a full accounting of road safety. Extensive literature and common sense both dictate that all crashes are not ‘created’ equal—with fatalities costing society more than 1000 times the cost of property damage only crashes. Despite this glowing disparity, the profession has not unanimously embraced or successfully defended a non-arbitrary severity...
Skid resistance is one of the important serviceability indicators related to safety on wet pavements. There is a need to manage skid resistance systematically to maintain the level of safety performance of roadway surfaces. This study focused on the development of a skid resistance deterioration model based on the analysis of skid data inventory collected in California. The California Department of Transportation (Caltrans) has collected skid resistance data across the complete state highway network over the past two decades using a standard locked-wheel skid trailer, ASTM E-274. This...
Largely in response to several landmark safety studies, as an official or unofficial policy, many agencies across the U.S. have elected to remove marked crosswalks at uncontrolled intersections, or have shown resistance to installing them in the first place. This approach results in unacceptable pedestrian mobility restrictions, yet such restrictions are often not considered in policy-making. As such, there is a need for roadway system owners to develop strategic safety guidelines to address the marked crosswalk dilemma. Since 2005, the UC Berkeley Traffic Safety Center, in a study funded...
This report presents the results from a multiyear effort to develop and test performance measures for evaluating the impact of landscaping and roadside features on pedestrian and bicyclist safety and mobility and economic vitality for Caltrans’ urban arterial network. The first phase of the study was a literature review, and the second phase focused on developing performance measures. The third and fourth phases focused on testing the proposed performance measures consisting of an infrastructure analysis, policy review, safety analysis and a pedestrian and bicyclist intercept survey on two...
In this paper we use a case study approach to examine how airport operators are addressing bicycle access to their properties and the motivations and obstacles they face, in light of new policies to integrate bicycles, along with transit and walking, into transportation planning, design and construction, and to increase bicycles’ role in the transportation system. Eight influential elements emerged from our review of policy documents and research literature. We used them to guide interviews with key informants. The eight elements are: governance structure, location, access roads, self-...
This project evaluates the feasibility of developing a pedestrian and bicycle infrastructure database and volume database for the California state highway system. While Caltrans currently maintains such data for motor vehicles in the Traffic Accident Surveillance and Analysis System - Transportation System Network (TASAS-TSN) database, the agency does not keep records on pedestrian or bicycle facilities. This information is crucial for improving the safety of these vulnerable road users. This project developed a proposed database structure and corresponding data collection methodology. It...
This white paper examines the social equity impacts of various congestion management strategies. The paper includes a comprehensive list of 30 congestion management strategies and a discussion of equity implications related to each strategy. The authors analyze existing literature and incorporate findings from 12 expert interviews from academic, non-governmental organization (NGO), public, and private sector respondents to strengthen results and fill gaps in understanding. The literature review applies the Spatial – Temporal – Economic – Physiological – Social (STEPS) Equity Framework (...
