Integrating Travel Time Reliability into Transportation System Management

Chapter 1. Introduction

With technical support from the Federal Highway Administration (FHWA), transportation organizations across the United States have been making progress toward integrating transportation systems management and operations (TSMO) into the metropolitan and statewide planning processes over the past 15 years. As a result, collaboration and coordination between planners and transportation system managers and operators has increased but there are still gaps that can lead to less efficient or effective transportation investments.

In addition to the work done by the FHWA, the purpose of the Second Strategic Highway Research Program (SHRP2) (2006 – 2018) was to find strategic solutions to three National transportation challenges: improving highway safety, reducing congestion, and improving methods for renewing roads and bridges. One of the primary focuses of the SHRP2 reliability research was to develop or enhance data and analysis tools to support the evaluation and modeling of travel time reliability that is necessary for including reliability in planning and decision-making.

This report documents an FHWA project led by the Office of Operations to address the gaps between planning and operations. Its intent is to evolve the state of the practice by building a methodology supported by the data and analysis tools developed under the SHRP2 program. This FHWA project, Integrating Travel Time Reliability Analysis into Transportation System Management, began in mid-2017 and was completed in early 2019.

Project Motivation

At a fundamental level, this project concerns linking long-range transportation planning to more detailed, tactical operations decisions made at the corridor or network level. Its goal was to address the disconnect between the system-level goal- and objective-setting that happens in the planning process and the operations planning that occurs at a lower level, primarily among operators.

Frequently, statewide or regional transportation goals and objectives are fairly high level and long range, they cover the entire system, and they may not fully include operational or travel time reliability needs. On the other hand, transportation system managers and operators often select and deploy operational tactics at the network or corridor level without developing operational objectives or an overall strategy for managing the corridor or network. The outcome of this project is a methodology designed to help guide planners, operators, and system managers connect system-level planning and operational decisions by using travel time reliability for purposes ranging from developing broad, planning-level goals and objectives to implementing tactics.

The objectives for this project were to:

• Develop and demonstrate a method for integrating travel time reliability concepts, analysis, and related decision support systems into ongoing TSMO activities and programs as well as into TSMO strategies and tactics at the network and corridor levels.
• Show how this method can be used to connect planning-level reliability goals and objectives to more detailed operational objectives, TSMO strategies, and tactics.

Business Case

An important question to consider is why making this connection using data and analysis tools matters. What are the ramifications of not connecting system-level goals with tactics used on a corridor or network scale?

Intuitively, it makes sense that government agencies should do what they plan for and plan for what they do. Operational investments and tactics that are not developed as a means of achieving a higher-order objective or goal are much less likely to "move the needle" in terms of reaching agreed-upon goals or performance targets. Additionally, operational activities are not coordinated strategically across corridor or network boundaries to realize more performance benefits. This disconnect wastes time and money and leads to inefficient or ineffective solutions that may or may not address our greatest needs, detracting from the credibility of our transportation agencies. But by bridging this gap, the United States is better positioned to compete economically on a global scale.

Overview of Tasks

The work of this project was broken down into five tasks that will be revisited throughout this report (see figure 2). Task 1 covered the project initiation activities and prepared the team to undertake tasks 2 and 3. Task 2 consisted of a document review to better understand how transportation agencies, primarily State departments of transportation (DOTs) and metropolitan planning organizations (MPOs), incorporate reliability and operations performance measures, data, and tools into planning and system management. Task 3 focused on developing representative sets of system-level goals and objectives by first scanning planning documents to identify examples. To execute task 4, the project team hosted a workshop with planning and transportation system management experts at MPOs and State DOTs, and then developed and applied an analysis methodology to several hypothetical scenarios. Task 5 efforts were to document the project results through this report.