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28 Scenario The previous scenarios focused on interagency partnerships. However, even within agencies, consideration of network per- formance can help expand and integrate the solutions that transportation agencies apply to the challenges they face. Most DOTs and MPOs are organized by function (e.g., planning, project development, or operations) or by mode (e.g., high- way or rail) or both. This scenario focuses on linking planning and operations within a state DOT, though it may apply to other integration efforts as well. In many DOTs, there are well-established roles for planning and operations but often limited or no formal (or even informal) links between them. Planning typically coordinates transportation planning statewide, including identifying agency goals and objectives, evaluating and prioritizing projects and strategies, and evaluat- ing the agencyâs success in addressing transportation challenges. DOTs are increasingly recognizing the value of system man- agement and operations as both a fundamental responsibility and a strategy to tackle congestion. Operations responsibilities include some or all of maintenance, traffic, safety, and intelli- gent transportation systems (i.e., roadway monitoring, inci- dent management, traveler information, and operation of traffic management centers). Though significant progress has been made in improving management and operations, planning and operations func- tions have not typically coordinated on issues that they share in common, such as congestion. Improving the linkages between these two functions can improve system performance by help- ing to coordinate transportation investments and improve data collection strategies and data sharing. Case Studies Recently significant attention has been paid to linking plan- ning and operations functions at DOTs and MPOs. FHWA has conducted several recent best practice studies of these efforts and released separate guidebooks directed toward MPOs and DOTs. The case studies most directly relevant to this scenario come from the Oregon and Washington State DOT efforts using system-level performance measures. The Oregon Transporta- tion Plan (OTP) is a statewide effort that looks at transporta- tion system needs across all transportation modes. The OTP includes an assessment of the impacts of transportation sys- tem operations investments relative to capacity investments and includes a rigorous performance analysis of several plan scenarios. The Washington State Department of Transportation (WSDOT) provides a unique example of an agency that has applied management tools to nearly every aspect of agency business. The agency publishes a comprehensive quarterly performance report called the Gray Notebook that guides decision making in congestion management, including capi- tal planning, demand management, and operations. The WSDOT approach provides reliable data that can be applied across agency business (planning and operations) and creates consistency, allowing for overall buy-in and agreement by both legislators and the public. In addition, this section draws examples from recent and ongoing research to supplement the case studies that were con- ducted for this effort. The research for this guidebook focused primarily on interagency partnerships, not individual agencies. Building Blocks Establish Partnership Agreements In a typical state DOT, the roles of and responsibilities for planning and operations fall within separate and distinct departments. Coordination between these departments can improve how the agency tackles congestion. Though a partner- ship agreement within a single agency may seem unnecessary, some formal or informal agreement helps ensure coordination. C H A P T E R 7 Intra-Agency ScenarioâLinking Planning and Operations at a State DOT
A review of state DOTs that successfully link their planning and operations functions revealed that all of them had a board or committee to coordinate these two functions broadly. These committees facilitate activities of mutual interest such as ⢠Developing network performance measures that are con- sistent across the agency; ⢠Coordinating the collection and storage of data and devel- oping tools for data access. (Operations collects data from public [and sometimes private] sources to support incident management and traveler information. Planners increas- ingly recognize that such data can supplement data used for planning studies and travel forecasting.) ⢠Identifying strategies to address nonrecurring congestion in statewide, regional, and corridor studies, and congestion management; ⢠Developing models to quantify the impacts of operational investments for easier comparison to capacity expansion; and ⢠Overseeing the execution of the mobility-oriented strategies and objectives from a long-range plan. The OTP update was developed by the Transportation Devel- opment Division of the Oregon DOT but had substantial support from other divisions to estimate transportation sys- tem need and analyze scenarios. As part of the OTP update, a âMaximum Operationsâ scenario was defined in coordination with the Office of Operations. consistency. Planning and operation collaboration provides decisionmakers with network performance measures that address a range of investment strategies, including measures of system reliability. Traditional mobility performance mea- sures (e.g., volume-to-capacity [V/C] ratios) cannot effec- tively assess the reliability and safety benefits of operational investments and should be supplemented with operations- oriented measures. WSDOT uses a suite of measures to identify and prioritize congested corridors. The network includes major interstates and arterials in and around Seattle, Tacoma, and Olympia. With many corridors experiencing some congestion, tradi- tional metrics such as LOS yielded billions of dollars of needs over a 20-year time frame. WSDOT began to use measures of throughput efficiency to narrow the deficiency list by roughly one-third and focus scarce resources on the most needed corridors. The department uses maximum through- put to select projects for the state transportation improve- ment program. Network performance measures helped convince WSDOT management that capacity solutions must be supplemented by operational solutions. Performance measures have helped justify expanded investments in operations, such as inci- dent response and demand reduction programs. WSDOT uses before-and-after evaluations of operations projects to demonstrate their benefit in terms of reduced travel times or delay avoided. 29 Mobility Council The Maryland State Highway Administration created a âMobility Councilâ to oversee mobility and congestion relief performance measures, one of six key performance areas that are part of the agencyâs strategic plan. The Mobility Council includes representation from planning, traffic, safety, and incident management. The Mobility and Congestion Relief performance measures include objectives and associated performance measures for Incident Congestion Delay and Recurring Congestion Delay. In 2005, the National Transportation Operations Coalition (NTOC) identified and defined a num- ber of potential key operations performance measures of national significance. Under NCHRP Project 20-7, Guide to Benchmarking Operations Performance Measures, the NTOC measures were pilot tested and refined (Table 7.1). These measures can be used as a starting point by state DOTs to identify and implement intra- agency network performance measures that support planning and operations functions. Define Performance Measurement Framework Traditionally, operations and planning staff have used separate performance measures with little coordination or Develop Measurement and Data Collection Methodologies Data Collection Both planning and operations functions make use of data, but often for different purposes. Planning typically uses data
from a relatively small number of traffic recording stations strategically placed throughout the state for planning studies. DOTs also often have hundreds of traffic-monitoring devices on both highways and arterials that provide real-time data for incident management and traffic information. In addition, DOTs are examining possible system enhancements that make use of probe data collection devices (such as Bluetooth) and other new technologies to augment existing data collec- tion efforts. Increased coordination of planning and opera- 30 Table 7.1. Potential operations performance measures. Performance Measures Definition Average peak travel time ⢠Facility: Average time required to traverse a section of roadway during peak travel period ⢠Reliability: Includes the additional time that must be added to a trip to ensure a traveler will arrive at a destination at, or before, the intended time 95% of the time ⢠Trip: The average time required to travel from origin to destination on a trip that might include multiple modes during peak period Throughput ⢠Person: Number of persons traversing a facility section or screen line per unit time ⢠Vehicle: Number of vehicles traversing a facility section or screen line per unit time Speed ⢠The average speed of vehicles measured in a single lane, for a single direction of flow, at a specific location on a roadway Recurring delay ⢠Vehicle delays that are repeatable for the current time of day, day of week, and day type Nonrecurring delay ⢠Vehicle delays in excess of recurring delay for the current time of day, day of week, and day type Incident duration ⢠The time elapsed from the notification of an incident until all evidence of the incident has been removed from the incident scene Extent of congestion ⢠Spatial: Miles of roadway in an area and time period with average travel times 30% longer than unconstrained ⢠Temporal; The time duration during which more than 20% of the roadway sections in an area are congested as defined by the Spatial Extent of Congestion performance measure Source: Adapted from Guide to Benchmarking Operations Performance Measures, NCHRP 20-7. Relevant Data and Analysis Practices Caltrans, working with the University of Califor- nia, has developed a real-time performance measurement system (PeMS) for freeways. The system provides real-time freeway performance information and can perform detailed quick- response analysis on historical freeway perfor- mance, primarily through data from detectors. (https://pems.eecs.berkeley.edu/) The Maryland State Highway Administration, working with the University of Maryland and several partners, has developed the Regional Integrated Transportation Information System, which serves as an archive and provides numer- ous data query tools for incident data, traffic detectors, and third-party probe data. Georgia DOT Traffic Management Center staff developed a set of data validation checks and a quality assurance plan to smooth raw data gaps and increase the overall quality of data to levels tions functions has benefits for data collection and storage, including ⢠Increasing the usability of archived data for both opera- tions and planning staff through improved access tools and greater attention to data quality; and ⢠Repurposing data between planning and operations to improve the efficiency of data collection and the robustness of analysis. Sharing data also presents challenges. Planners, for example, need detailed and accurate volume, speed, and classification data for forecasting, while operations staff, more interested in quickly finding incidents, have a higher tolerance for less accuracy. Analysis Tools Planning typically makes use of regional or state travel demand forecasting models, project- and corridor-specific meso- and microsimulation models, and sketch-planning tools. Increasingly, planning staff are recognizing the need for tools to evaluate operational investments within the planning process so that these investments can be considered alongside capacity investments. There is a range of tools, including sketch-planning, microsimulation models, and custom mod- els for major incidents (e.g., hurricane evacuation).
31 Planning and Operations Coordination in the Use of Analysis Tools The Maryland State Highway Administration and the University of Maryland have developed an evacuation planning tool (http://oceancity. umd.edu/index.php) to support evacuation of the stateâs eastern shore beaches and resort communities. The tool was developed by high- way operations staff; however, agency planning staff is interested in using the tool to conduct operational analyses for determining trans- portation system investments based on major incident scenarios, including evacuation of the stateâs eastern shore. satisfactory for other uses beyond operations, including planning. Planning staff now make use of such data in their studies. The Portland Oregon Regional Transportation Archive Listing (PORTAL) is the official Archived Data User Service for the Portland Metropolitan Region. PORTAL provides a centralized database that facilitates the collection, archiving, and shar- ing of information/data for public agencies in the region. PORTAL has been used to support (1) development of arterial performance mea- sures and (2) the regionâs congestion manage- ment process, transportation system plans, corridor plans, and system management and operations. (http://portal.its.pdx.edu/)
