Pilot Testing of SHRP 2 Reliability Data and Analytical Products: Southern California (2014)

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• Practical use: Do they help Southern California select and prioritize projects? Do decision makers understand the reliability analyses and find the results credible? In addition, SHRP 2 testing in Southern California benefitted from extensive automated detection and performance measurement through the Caltrans Performance Measurement System (PeMS). This is an Internet-based system that allows the extraction of real-time and historical performance data collected through automated sensors, such as loop detectors. Users can access PeMS with any computer using an Internet connection and standard web browser. The system includes a diagnostics function that attempts to identify data issues, and PeMS automatically estimates travel time reliability performance measures. Figure 1.2 shows an example of the extensive detection coverage available through PeMS. The green circles indicate detectors providing good data, while the red circles indicate sensors with bad data on the day the map was generated. The facilities analyzed as part of the Southern California pilot site are outlined on the map as well. Figure 1.2. Sensor coverage in the Southern California pilot site. Source: Caltrans Freeway Performance Measurement System (PeMS). pems.dot.ca.gov. 1.3 Organization of the Report The rest of this report provides detailed findings from the Southern California pilot site. The next two chapters describe the overall research approach taken for the Southern California pilot site and the selection of two facilities for testing (I-210 in Los Angeles County and I-5 in Orange County). Chapter 4 discusses the compilation of data for the reliability analysis and the application of the L02 guide to understand what factors affect reliability along the test facilities Los Angeles I-210 Orange I-5 20

as well as the contributions of these factors to unreliability. This is followed by three chapters dedicated to each of the reliability analysis tools included in the pilot testing: • C11 Reliability Analysis Tool (for incorporating reliability in benefit-cost analysis) • L07 Analysis Tool (for analyzing the effects of highway geometric design treatments) • FREEVAL-RL (for implementing proposed changes to the Highway Capacity Manual to incorporate reliability analysis). These chapters describe the calibration of the tools to the test facilities as well as their application to facility improvements previously identified by SCAG, Caltrans, and other stakeholders. Based upon these findings, the study team conducted a detailed benefit-cost analysis using the C11 tool and results available from microsimulation analyses. The benefit-cost findings are presented in their own chapter. After these findings, the study team summarizes observations from the analysis tools and outreach from stakeholders to conduct a functionality assessment of the products and outcomes. The functionality assessment considers the technical feasibility of products, decision maker perceptions, and potential impacts on decision making. A final chapter provides conclusions from the pilot testing along with a summary of suggested modifications to the SHRP 2 reliability tools and suggested research. 21

CHAPTER 2 Research Approach The Southern California pilot site conducted its SHRP 2 reliability product testing by leveraging existing CSMPs prepared for facilities in Southern California. Both SCAG and Caltrans have invested significant resources in the development of these CSMPs. The plans are intended to describe how a facility is currently performing, identify operational strategies and select system expansion opportunities that can improve performance, and quantify the likely benefits that result from these investments. CSMPs were initially developed for facilities that received funding from the California Corridor Mobility Improvement Account (CMIA), which was created by the passage of State Proposition 1B in November 2006. To a great extent, CSMPs were produced to complement existing expansion plans with value-added operational strategies, though Caltrans intends to prepare CSMPs for all major travel facilities in California and to update them periodically. Southern California has roughly a dozen facilities with completed CSMPs. Each plan includes a comprehensive performance assessment with data from PeMS and other sources to document mobility, safety, productivity, preservation, and travel time reliability. In addition, Caltrans has invested millions in developing microsimulation models for each Southern California CSMP that can quantify the mobility benefits of various operational and system management strategies on each facility. Each CSMP also includes benefit-cost analysis to demonstrate the cost effectiveness of proposed strategies. Currently, the benefit-cost analysis includes user benefits in terms of travel time savings, vehicle operating cost savings, and emission reductions. Although the comprehensive performance assessment describes travel time reliability, the benefit-cost analysis does not include reliability benefits because microsimulation modeling is unable to capture the reliability impacts of improvement strategies. The Southern California pilot site built on the tools and analysis available from the development of CSMPs. In addition to the comprehensive performance assessments and microsimulation models, the study team had travel demand models that identify origins and destinations along the facilities. As a result, the team had the pieces needed to conduct a deeper analysis of reliability causality, compare facilities, select the most appropriate facilities, and use the models already developed to forecast demand for the SHRP 2 tools. The study team tested several of the SHRP 2 products using the two CSMP facilities. The team selected features considered to be the most applicable to facility management planning in California and to have the greatest likelihood to help with developing California CSMPs, expanding benefit-cost analysis capabilities, and setting goals for the SCAG RTP/SCS. If the tools prove to be capable of supporting enhanced travel time reliability analysis, they may also help Caltrans set goals for the State Highway Operations and Protection Program (SHOPP) and develop operational playbooks for freeway facilities. 22

Table 2.1 summarizes the SHRP 2 reliability tools that the Southern California pilot site initially planned to include in its testing. The study team focused on the L02 methods for describing travel time reliability and contributing factors as well as the analysis tools for forecasting reliability and estimating impacts from L07, L08, and C11. The next several chapters discuss results from testing these tools. Table 2.1. SHRP 2 reliability products tested in the Southern California pilot site Type of Product L02 L05 L07 L08 C11 Methods for Describing Reliability and Contributing Factors  Suggested Alternative Strategies and Design Features   Tools for Forecasting Reliability and Estimating Impacts    Benefit Estimates for Benefit-Cost Analysis   Guidelines for Goal Setting  The team reviewed the L05 guide (Cambridge Systematics 2013) and found that it would not help the team in suggesting alternative strategies and design features. However, SCAG believes that the guide will be helpful in articulating the issue of system reliability, developing a framework for incorporating reliability into its planning and decision-making processes, and communicating the results to the stakeholders, members of the public, and decision makers as part of its next RTP. The guide may be helpful for local partner agencies, such as county transportation commissions and Caltrans, to utilize in local planning processes. This local focus for incorporating reliability into the decision-making process is based on how decisions for transportation investments are made in California. Self-help counties that have passed one or more voter measures to collect sales taxes dedicated to transportation control most of the funding. Even decisions for 75 percent of the funds administered by the state, such as federal and state gas taxes, are made by regional agencies. For example, the Los Angeles County Metropolitan Transportation Authority (Metro) controls more than $2 billion of annual transportation funds, significantly more than Caltrans controls. In addition to reviewing L05, SCAG played a critical role in the SHRP 2 product testing for other products. SCAG helped to select facilities for the Southern California pilot site. SCAG reviewed work products and provided feedback as a potential user of tools. Additionally, SCAG coordinated and facilitated input from the larger stakeholder group using its existing policy and technical committee structure. This included input from Caltrans district offices, county transportation commissions, and elected officials. 23

The study team split responsibilities for tool testing among team members. SCAG and its consulting partners were each responsible for testing on a facility. In this way, the study team was able to get hands-on feedback from a public agency perspective. To facilitate the testing of FREEVAL-RL and to ensure comparability of the SHRP 2 reliability testing, the study team used the modelers who were involved in microsimulation modeling on the CSMP facilities. In the end, the Southern California pilot site hopes to have better CSMPs and quantification of reliability for benefit-cost analysis and goal setting. Overall, the study team followed these general steps for the pilot testing: • Review facilities with existing CSMPs and select two of the most promising facilities for reliability improvement; • Compare reliability on the facilities and understand factors that affect reliability; • Use SHRP 2 tools to develop more detailed, robust analyses of travel time reliability; • Leverage available microsimulation models, travel demand models, detection, and automatic sensor data; • Test recently programmed or planned projects and potential operational strategies; and • Present results to SCAG policy and technical committees. The next chapter reviews the Southern California CSMP facilities and describes the two facilities selected for pilot testing. Subsequent chapters provide results and reviews for each tool. 24