Los Angeles County Metropolitan Transportation Authority (Metro) Arterial Performance Measures Framework Anita Vandervalk-Ostrander Iteris, Inc. Santa Ana, California, USA Steven Gota, Deputy Executive Office Los Angeles County Metropolitan Transportation Authority, CA, USA Viggen Davidian Iteris, Inc. Los Angeles, California, USA Lisa Young TransLink, Fullerton, California, USA Abstract Los Angeles County has over 5,000 miles of arterial streets which are maintained and operated by 89 local agencies within the county. This extensive network is an integral component of the overall Countywide multi-modal transportation system and is the vital link between the local/collector streets and the regional highways and freeways. The Los Angeles County Metropolitan Transportation Authority (Metro) launched a performance monitoring initiative in 2014 to assess the feasibility of developing a countywide Arterial Performance Measurement Program. The program includes arterial performance measures, data identification, corridor selection, analysis techniques, and testing analytical tools to demonstrate and visualize performance results. To date, the Program has achieved the following: 1. Demonstrated that the concept of a countywide Arterial Performance Measurement program is feasible and should be pursued. 2. Developed a Baseline Tool with arterial measures results for LA County 3. Assessed performance measurement vendor analytic packages 4. Conducted a Pilot Test as a proof of concept for the analytical tool and 5. Conducted extensive collaboration with LA County agencies, council of governments, and local cities through an outreach process. This paper provides an overview of the process and highlights the innovative approaches to this comprehensive arterial performance measures program featuring a variety of data sources and analytic tools. KEYWORDS: Arterial Performance Measures, Big Data, Analytic Tools - 1 -
Introduction Over the years, the Los Angeles County Metropolitan Transportation Authority (Metro) has been closely collaborating with its local partner agencies to implement a wide range of arterial improvements including signal synchronization, Intelligent Transportation System (ITS) investments, and bus speed improvements to improve mobility and reliability in the County. Understanding how well a transportation system performs will greatly help target the right projects to address local and regional mobility and reliability needs. In 2014, Metro conducted the Arterial Performance Measurement Framework initiative to assess the feasibility of developing a countywide Arterial Performance Measurement Program. The study demonstrated that the concept of a countywide Arterial Performance Measurement Program is feasible. To further provide a proof of concept, the Arterial Performance Measurement Pilot was initiated in 2017 to test a vendor analytical package within a sub region of Los Angeles County (LA County). The Arterial Performance Measurement Pilot tested the effectiveness of a performance monitoring analytical package for LA County s complex arterial and highway system. This paper is organized in the following sections: Framework Describes the goals, components and measures of the Framework Baseline Conditions Analysis Describes the process and results of the Baseline analysis Arterial Performance Measures Pilot Describes the results of the pilot test Framework The Countywide Arterial Performance Measure Framework is comprised of five components: performance measures, data collection/sources, data management, a performance measurement tool and provision of input to planning processes. These components are shown in the figure below. - 2 -
Figure 1 Components of the Arterial Performance Measures Framework The Framework was designed to accomplish the following goals: Support future deployment of operational improvements by participating agencies; Create a process to monitor and report on mobility performance on arterial corridors throughout the county; Identify a tool for a countywide Performance Measurement Program; Measure the effectiveness of arterial Transportation System Management (TSM) improvements after they are in place; Develop a continuous data source and archive available over time for cities to use for project planning and grant applications; Provide useful tools to support local agency and sub regional operations and planning efforts; and Develop consistent methods for mobility performance measures calculations and reporting countywide. The Framework is not intended to: Require additional data collection from cities; Include transit operations performance data; - 3 -
The recommended performance measures for the Framework were selected based on national and local research and were vetted extensively with outreach to regional stakeholders. The measures are as follows: vehicle hours of delay, person hours of delay, travel-time variability, travel-time reliability, vehicle miles traveled, average travel speed, and average travel time. The data required to support these measures includes travel time, speed, volume, vehicle occupancy and certain roadway characteristics to allow for integrating the data. Extensive stakeholder collaboration occurred with the following groups: All cities within Metro, California Department of Transportation (Caltrans), County of Los Angeles Department of Public Works (LA DPW), City of Los Angeles (LADOT), Gateway Cities, North Los Angeles County, San Gabriel Valley, South Bay Cities, Westside Cities, Las Virgenes/Malibu, San Fernando Valley and Southern California Association of Governments (SCAG). The Stakeholders agreed to a recommended arterial network for collecting and reporting data and performance measures. It is a combination of the Countywide Significant Arterial Network (CSAN) and the Countywide Significant Truck Arterial network (CSTAN) and is shown in Figure 2 below. Figure 2 Recommended Network Improved data management will be an important outcome of the Framework. This improved data management will be evident through the following capabilities: Support regional stakeholders in carrying out various goals and targets related to mobility these include performance measures reporting, data analysis, and before/after project analysis. Provide regional stakeholders with access to available archived travel time, speed, occupancy, volume, traffic signal systems operations data, and vendor probe data for the Framework network. All participating jurisdictions/agencies will have access, including any available data archived the previous day. This is not intended to provide real-time data. - 4 -
Support regional stakeholders as they conduct network analyses at both network and corridor levels. The corridor level analysis should allow for user selection of begin and end points for reporting. It should also include consistent methods for mobility performance measures calculations and reporting. Enable regional stakeholders to build, execute, save, and manage simple queries of the data. Allow regional stakeholders to export and/or display the results in a variety of standard file formats. Include data quality control statistics and flags with all query results. Baseline Conditions Analysis This stage of the project evaluated the performance of arterials throughout Los Angeles County to provide agencies and stakeholders with a detailed, reliable assessment of service on each part of the network, and to establish a baseline for evaluation of various arterial improvements and investments. To facilitate consistent and ongoing performance reporting, the project team developed a custom performance measurement methodology and data processing tool, which provided stakeholders with on-demand access to several key performance metrics at various levels of aggregation. This was a significant undertaking given the expansive arterial network in Los Angeles County with its nearly 20,500 miles of city and county road and tens of thousands of intersections. With the collaboration of partner agencies, this stage achieved the following key objectives: Established a list of arterials for the analysis; Conducted traffic counts on major arterials; Processed INRIX crowd-sourced speed data; Built an APM for each sub region; and Developed the Baseline Conditions Reports. Arterial Performance Measurement Pilot The Arterial Performance Measurement Pilot tested the effectiveness of a performance monitoring analytical package for LA County s complex arterial and highway system. The purpose of this pilot was to evaluate an analytics package that could best serve LA County and its sub regions. The objectives of this Pilot Project were to: Evaluate and test an Arterial Performance Monitoring Tool to assess arterial network performance; Conduct a pilot test based on a sub region in LA County; Utilize comprehensive arterial volume and travel time data; Collect user group input and assessments; and Demonstrate applicability for other sub regions. Using a combination of recent third party speed data and volume data collected as part of the Countywide Baseline Conditions project, the Pilot Project evaluated the performance of arterials using the described above (average speeds and travel times, vehicle and person miles traveled, and vehicle and person hours of delay.) Based on an evaluation of transportation performance measures, usability, technical and cost criteria as described in the Arterial Performance Measurement Framework, ipems offered the most applicable use for the Arterial Performance Measurement Pilot. Key elements of the Arterial Performance Measurement Pilot s vendor analytical tool include: A countywide cloud-based dashboard available to local agencies; Ability to evaluate arterials within an LA County sub region; Builds on data collected in the Countywide Baseline Conditions Analysis, including traffic count and speed data; Allows for customizable reporting on arterial performance for a variety of metrics; Customizable routes to evaluate a variety of facilities and services; and Streamlines the process for reporting on arterial performance projects. - 5 -
To conduct the Pilot, the team collected two months of data into a database for the selected region. All (the entire LA County) historical traffic data from Inrix was input into ipems. Using ipems and associated data set, the team conducted a pilot test including collection, analysis, integration and reporting of data and performance measures for a subset of the region using the approved data set. Results from the Pilot Project demonstrated Metro s commitment to its Intelligent Transportation Systems (ITS) and the operational and monitoring goals for LA County. - 6 -