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Traditional tools, including travel demand and microsimulation modeling, have to date not been able to adequately estimate the reliability benefits of projects. As a result, the SHRP 2 reliability products have the potential to fill a void in the ability to analyze reliability impacts and quantify likely benefits of operational strategies. The SHRP 2 products need to be tested on real facilities using complex data sets and within complex political processes. The SHRP 2 L38 project is intended to provide the necessary testing and feedback on existing SHRP 2 reliability tools. The RFP for SHRP 2 L38 provided the following objectives: 1. Assist agencies in moving reliability into their business practices through testing of data integration and analytical tools developed by SHRP 2. Include a data collection/integration component, an analytical component, and a decision-making component. 2. Provide feedback to SHRP 2 on the applicability and usefulness (benefits and value) of the products tested. Suggest potential refinements [to the products tested]. Pilot testing under the SHRP 2 L38 project occurred at four separate sites in Florida, Minnesota, Washington State, and Southern California. This report describes the approach and findings from the Southern California pilot site. Pilot testing at the other three sites was conducted simultaneously by different study teams under separate contracts. However, the study teams for the four pilot sites interacted multiple times and were able to share ideas on product testing. 1.2 Southern California Pilot Site The Southern California pilot site is one of the most congested regions in the United States. The Texas Transportation Institute 2012 Urban Mobility Report ranks the Los Angeles-Long Beach- Santa Ana urban area second to the Washington, D.C. metro area in terms of yearly delay per auto commuter. The Los Angeles area ranks first in terms of having the worst travel time index (i.e., the ratio of travel time in the peak period to the travel time at free-flow conditions) and ranks either first or second worst in several travel time reliability measures (Texas Transportation Institute 2012). Clearly, this is a region where reliability improvements are needed. The Southern California pilot site conducted a practical, yet critical evaluation of the SHRP 2 products and concepts developed to date with an emphasis on analyzing operational strategies that can mitigate the regionâs travel time reliability issues. The study team performed its testing in conjunction with the Southern California Association of Governments (SCAG) and the California Department of Transportation (Caltrans). SCAG is the largest metropolitan planning organization (MPO) in the United States. It represents six counties, 191 cities, and more than 18 million residents. The agency has a long history of performance-based transportation planning and recognizes the importance of 17
operational strategies. SCAG played a very active role in the SHRP 2 L38 evaluation by helping to select facilities for testing, conducting hands-on testing of the SHRP 2 reliability tools, reviewing work products, providing feedback on the tools, and soliciting input from the larger stakeholder group within the region. In April 2012, the SCAG Regional Council, which is comprised of over 90 locally elected officials, unanimously adopted the 2012â2035 Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS). Figure 1.1 shows the goals adopted by the Regional Council and included in the 2012 RTP/SCS. As shown in the figure, ensuring travel reliability is one of the regional goals. The RTP/SCS goes a step further and includes a specific reliability goal with a 10-percent improvement benchmark (SCAG 2012). SCAG would greatly benefit from methods that help to quantify future reliability improvements, especially since its Regional Council has directed staff to work on further quantification of performance measures. RTP Goals Align the plan investments and policies with improving regional economic development and competitiveness Maximize mobility and accessibility for all people and goods in the region Ensure travel safety and reliability for all people and goods in the region Preserve and ensure a sustainable regional transportation system Maximize the productivity of our transportation system Protect the environment and health for our residents by improving air quality and encouraging active transportation (non-motorized transportation) Actively encourage and create incentives for energy efficiency, where possible Encourage land use and growth patterns that facilitate transit and non-motorized transportation Maximize the security of the regional transportation system through improved system monitoring, rapid recovery planning, and coordination with other security agencies Figure 1.1. SCAG 2012 RTP/SCS goals. Source: SCAG, 2012-2035 Regional Transportation Plan and Sustainable Community Strategy In addition, the 2012 RTP/SCS also provided a high-level regionwide estimate for potential improvements in reliability for three different hours during the day. These improvements were expected as a result of the operational investments, particularly through 18
improved incident management. The estimates presented in the SCAG RTP/SCS were based on the Corridor System Management Plan (CSMP) efforts in the SCAG region. As part of the SHRP 2 L38 evaluation, SCAG helped the study team navigate the complex organizational relationships and decentralized decision making found in Southern California. Many funding decisions are made at the local or regional level due to the presence of self-help counties. These are counties in which voters have voluntarily agreed to tax themselves to pay for transportation improvements. For example, Los Angeles County has enacted a combination of permanent and temporary measures that dedicate a combined total 1.5 percent sales tax to transportation. As a result, SCAG took a lead role in coordinating public agency participation for this SHRP 2 L38 effort. The stakeholder group included elected officials, county transportation commissions (CTCs) and Caltrans district offices as well as some of the larger local operators, such as the Los Angeles County Metropolitan Transportation Authority (LA Metro). SCAG assisted in convening transportation stakeholder group meetings as necessary, relying on its existing policy and technical committee structure as forums for additional dialog with the stakeholders and decision makers. SCAG included a written update on the SHRP 2 L38 project in its consent calendar for the Transportation Committee. SCAG also held a meeting with its technical working group on December 18, 2013. Caltrans is committed to system management. The agency has formally adopted what it terms the Mobility Pyramid, which focuses on the importance of operational strategies. As a champion of system management, Caltrans is interested in research that furthers its commitment to funding operational strategies, especially given its role in improving interregional mobility. Although Caltrans played a less direct role than SCAG in the SHRP 2 pilot testing, Caltrans provided feedback on facility selection, the SHRP 2 reliability products, and the results of the reliability evaluations through its district offices. For example, the study team met with Caltrans District 12 in Orange County on January 28, 2014, to review the study findings and gain additional stakeholder perceptions from senior level management at the district. Caltrans District 12 is very familiar with the concept and use of reliability measures since each of the freeways in Orange County has had a reliability evaluation performed as part of the CSMP efforts in that district. For each CSMP, the buffer index was calculated for non-holiday weekdays for both mainline and high-occupancy vehicle (HOV) lanes. During the January 28 meeting, Caltrans district management was interested in learning more on how reliability assessments, particularly through the work done on L02, could be applied in the district and communicated this to the Orange County Transportation Authority (OCTA), which controls most of the funding within the district. By engaging these âadvanced users,â the Southern California pilot site tested two aspects of the SHRP 2 products without the need to introduce the travel time reliability concept: ⢠Technical functionality: How easy are the products to use? How consistent are they with each other and prior work? 19
