Strengthening Linkages between Transportation Demand Management and Traffic Management

Executive Summary

Transportation system users face many choices when planning their entire travel trip. Destination, mode, route, time-of-day, and what facility or lane are types of choices for travelers to consider and all have implications for transportation system management. These choices provide opportunities for public and private agencies to inform traveler decisions for both the traveler's and the transportation system's benefit. Linking transportation demand management (TDM) and traffic management enhances the ability for transportation stakeholders to address mobility and reliability concerns in travelers' decision-making processes and enable users to make informed decisions throughout their trip.

TDM addresses how and when people need to travel, and traffic management addresses how users traverse the transportation system efficiently. Traditionally, separate unconnected programs are responsible for managing travel demand on the transportation system and managing the resulting traffic from that demand. Traffic management strategies include incident management, arterial management, smart work zones, dynamic shoulder use, ramp meter, and emergency transportation operations. TDM strategies include bike and pedestrian support, first and last mile services, employer outreach, travel planning, mobility on demand, guaranteed ride home programs, and shared mobility modal support.

The difference between TDM and traffic management has become less distinct in recent years due to more targeted, actionable information that can improve traveler choices. Strategies that offer opportunities for TDM and traffic management collaboration include traveler information, priority treatment (e.g., transit signal priority), and toll operations and high-occupancy vehicle lane management. The concept of active transportation and demand management (ATDM) provides a framework to understand TDM and traffic management strategies as a holistic approach to manage traveler choices.

The Federal Highway Administration recognizes the possibility for ATDM to help transportation facilities and mass transit services achieve operational objectives, such as improved throughput, maximized system efficiency, reduced emissions, or improved safety.

The purpose of this report is to illustrate examples of linking TDM and traffic management to achieve improved outcomes of travel reliability and access. The document presents real-world examples of how State and local traffic managers and demand management professionals can work together to achieve common goals. This report does not establish any new requirements or replace any existing guidance.

The case studies of the report are organized into seven context areas:

1. Managing demand and traffic during weather events and natural disasters.
2. Linking TDM and traffic management as part of transit disruption.
3. Incorporating TDM as part of a major road reconstruction project.
4. Managing system efficiency using active demand management and active traffic management.
5. Using high-occupancy toll (HOT) and priority treatments for transit service enhancements.
6. Managing special events using parking, TDM, and traffic management.
7. Managing smart parking and considering local traffic management.

Each case study addresses the strategies that promote traveler choices for different choice types. The types of choices that are considered are as follows:

• Destination choice: where would the user like to go?
• Mode choice: what transportation mode will the user take?
• Route choice: which roads will the user take?
• Time-of-day choice: when will the user take the trip (off-peak or peak travel hours)?
• Facility or lane choice: what specific facility options are available and which will user choose?

Table 1 briefly summarizes the case studies that show how TDM and traffic management were combined to address a specific issue, the strategies implemented, if and how they affected a portion of the trip chain, and any opportunities for future improvement.

Table 1: Case studies of notable practices for integrating travel demand management (TDM) and traffic management.

Case Study	Notable Practice
Hurricane Harvey Mobility Response—Houston TranStar	Leveraged existing relationships to disseminate accelerated and coordinated information about 500+ road closures
Utah Department of Transportation's Traffic Operations Center Use of Proactive Messaging during Weather	Provided streamlined, proactive messaging and signal adjustments through centralized Traffic Operations Center, which was able to analyze and distribute weather information in-house
SafeTrack—Washington, DC	Coordinated among agencies to divert users to alternate modes Encouraged employers to offer telework options, promoted bikeshare/carsharing, promoted bus ridership and implemented policies to improve bus service
Amtrak New York Pennsylvania Station Emergency Repair Work	Developed mitigation plan to increase capacity on unaffected transit lines, reduce road congestion through roadside traffic management information, and inform travelers about alternative route and mode options
New Jersey Pulaski Skyway Reconstruction	Began proactive outreach and coordination two years before construction Coordinated with transportation agencies to provide continuous information and communication to travelers about alternate route options
Texas I-35 Freight Trip Optimization with Construction Information	Integrated data-sharing systems to improve information on current and forecasted travel conditions
Atlanta's I-85 Bridge Collapse	Communicated across agencies to disperse traffic amongst alternative modes Reopened registration period for existing TDM program
New York State Department of Transportation's ATDM Program	Merged programs into a single ATDM program to ensure that project funding decision-making would consider and incorporate both TDM strategies and traffic management strategies
Houston's ConnectSmart Program	Created a single app platform to integrate payment and route planning across an 8-county region Collaborated among agencies to provide baseline data, collect and analyze future data, and react with appropriate management strategies
Mopac Improvement Project (Mopac Express Lanes)	Created of HOT lanes to provide more reliable travel times Offered toll exemptions to buses and vanpools to encourage shared-use modes
I-110/I-10 Express Lanes High-Occupancy Vehicle (HOV)Incentives (Los Angeles County)	Converted HOV to HOT lanes to provide option of free-flow traffic lane Offered financial incentives to vanpools and transit riders through loyalty program to encourage shared-use modes
I-55 Buses on Shoulder (Chicago Region)	Provided more reliable travel times for commuter buses by allowing bus travel on shoulders when general purpose lanes are slowed below certain speeds Partnered with public transit and vanpool providers and regional and State transportation agencies
Union Cycliste Internationale Road World Championships (Richmond, VA)	Began pre-event planning across multiple agencies began two years before event Communicated consistently with employers about the plan for road closures, which would change routes due to the race Dry run of event for a smaller race
Mass Transit Super Bowl (New Jersey and New York)	Created "Playbook" transportation plan to inform travelers who might be unfamiliar with transit options Enhanced capacity and efficiency of rail, added bus capacity, halted construction during event
Wyoming Department of Transportation and the 2017 Solar Eclipse	Released proactive messaging on VMS to discourage behavior that would be unsafe or reduce flow of traffic in rural area during rare event Communicated clearly about parking and viewing locations leading up to event on website
SFpark: Managing Parking Demand via Pricing (San Francisco, CA)	Integrated of technology and data to provide demand responsive parking program in order to maintain parking availability on every block

The case studies included in this compendium show some easy strategies, some unique strategies, and some strategies requiring more buy-in or support—but all implementable and supportive of both TDM and traffic management goals. Regardless of the contexts described in the compendium, agencies seem to consistently rely on three tactics to integrate TDM with traffic management efforts:

• Establishing supportive policies.
• Making temporary changes to existing programs and systems.
• Finding new communications and partnership strategies.

Through the strategies described in the compendium, State and local agencies can support the traveling public in making choices, every single day, about the most efficient and effective mode, route, time, and destination for their travels. Ultimately, this helps traffic managers achieve the broader goal of increasing person throughput throughout an entire transportation system.