International Technology Scanning Program January 2011

In cooperation with:

American Association of State Highway 

and Transportation Officials

National Cooperative Highway

Research Program

Sponsored by:

Integrating Active Traffic and

Travel Demand Management:

A Holistic Approach to Congestion Management
NOTICE

The Federal Highway Administration (FHWA) provides high-quality 

information to serve Government, industry, and the public in a 

manner that promotes public understanding. Standards and 

policies are used to ensure and maximize the quality, objectivity, 

utility, and integrity of its information. FHWA periodically reviews 

quality issues and adjusts its programs and processes to ensure 

continuous quality improvement.
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 1

[ ATM | TDM ]

Contents

Background and Primer Purpose ........................................................... 3

How Actively Managing Traffic and Travel Demand Relate: Dutch Model of 

Travel and Traffic Management ............................................................. 5

Integrating ATM and TDM: Definitions and a New Perspective .................................... 8

Examples of ATM and TDM Integration..................................................... 11

Proposed Approach for Integrating ATM and TDM into a Holistic Program ........................ 16

Summary............................................................................. 18

Resources ............................................................................ 19

Figures

Figure 1. Dutch model of travel demand and traffic management. ................................ 5

Figure 2. Overhead display in Germany....................................................... 7

Figure 3. Sign to slow traffic because of fog. .................................................. 7

Figure 4. Influencing travel behavior process. ............................................... 10

Table

Table 1. ATM strategies and potential benefits. ................................................ 9
2

[ ATM | TDM ]

Acknowledgments

This primer was prepared by Eric N. Schreffler, transportation consultant at ESTC, for the 

Federal Highway Administration’s (FHWA) Offices of Transportation Management and 

International Programs. It draws information and inspiration from two international 

technology scanning reports on managing travel demand and active traffic management. 

The author would like to thank FHWA staff who oversaw and reviewed the primer, 

including Wayne Berman, Allen Greenberg, Greg Jones, Hana Maier, Jon Obenberger, 

Robert Sheehan, Jessie Yung, and Grant Zammit. Chuck Fuhs, Chris Wellander, and 

Liz Young of Parsons Brinkerhoff, working on a related report, also provided invaluable 

input. Organizations that provided information for the case studies in the primer include 

the California Center for Innovative Transportation, IVV Aachen, Puget Sound Regional 

Council, Organizational Coaching, United Kingdom Highways Agency, and Washington 

State Department of Transportation. 
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 3

[ ATM | TDM ]

T

he concept of active traffic management (ATM) is 

gaining traction in the United States as examples 

from Europe are explored and discussed. Indeed, 

a 2006 Federal Highway Administration (FHWA) 

International Technology Scanning Program study to 

explore experience with managed lanes in Europe 

revealed that managed lanes (including high-occupancy 

toll lanes) were not being implemented in Europe. 

Instead, the concept of ATM was studied in the German 

state of Hesse, the Netherlands, and the United Kingdom. 

The concepts brought back from Europe have created 

considerable buzz in the transportation community as 

regions seek new and better ways to address traffic 

congestion. ATM holds the promise of greater efficiency 

and throughput on congested facilities via a host of 

real-time, dynamic traffic management techniques.

Another scanning study, conducted in 2005, on the 

concept of managing travel demand (synonymous with 

travel demand management (TDM)) also looked at ATM 

in the Netherlands and the United Kingdom. This scan 

covered other travel demand-reduction strategies, such 

as congestion pricing, new institutional arrangements to 

address demand management, and the use of traveler 

information to influence travel before and as it occurs. 

The conclusion of the scan on managing travel demand 

was the need to integrate the philosophy of managing 

demand into both the long-range transportation planning 

process and the daily management and operation of the 

highway system. This need to integrate TDM into highway 

operations, consistent with FHWA’s emphasis on managing for operations, is at the heart of this primer.

The purpose of this primer is to introduce and define 

the ATM and TDM concepts and show the need for and 

benefits of integrating the concepts into efforts to address 

congestion on the most affected facilities. The primer 

provides a conceptual framework, originally suggested 

by the Dutch Ministry of Transport, for understanding 

the difference between traffic management and travel

demand management. In a nutshell, managing travel 

demand is effectively addressing congestion before 

the decision is made on when, how, and whether to 

use a car. Managing traffic is efficiently addressing 

congestion once the traveler is in the automobile or 

has made the decision to use a car. The primer underscores the need to integrate the two concepts into a 

holistic approach to congestion management. The term 

“holistic” is fitting in that it is a theory that views things 

as integrated wholes, rather than the mere sum of the 

elements. Considered alone, each concept presented in 

this primer is neither new nor innovative. The concepts 

have been tried and tested one place or another, many 

in the United States. What is new and innovative is the 

call to consider an integrated approach from the earliest 

planning stages of efforts to address congestion in a 

given region, system, or corridor.

This integrated, holistic approach has not been adopted 

in the United States or Europe. Therefore, this primer 

focuses more on the conceptual foundation and need 

for integration than on examples of how and where the 

integrated approach has been tested. The examples are 

illustrations of the linkages between TDM and ATM rather 

Background and Primer Purpose

This primer deals with the need for and benefits from 

integrating two innovative concepts in congestion 

management: active traffic management and travel 

demand management. This document considers the 

following:

`How the two concepts relate to each other and the 

need for integration

`Types of integration, with examples

`A proposal to integrate ATM and TDM into a 

holistic approach for managing congestion
4

[ ATM | TDM ]

than full case studies on integrated, holistic approaches 

that have been planned, implemented, and evaluated. 

The primer does not include extensive discussion of 

perhaps the most effective demand management strategy: congestion pricing. While pricing needs to be a key 

consideration in any holistic treatment of congestion, 

it is covered in a more exhaustive manner in the FHWA 

Congestion Pricing Primer Series (see Resources). Ramp 

metering and other access controls are hybrid techniques 

that fall between managing demand and managing 

traffic. Ramp metering modulates the flow of traffic onto 

a congested facility, but in general it does not reduce 

overall demand for car travel during congested periods, 

which is the focus of TDM.

The primer describes five types of ATM and TDM 

integration and provides examples of each, drawn 

from the United States and Europe. The following 

are the five types of integration:

`New partnerships for integrating ATM and TDM

`Enhanced travel alternatives in actively managed 

corridors

`Incentives to reduce traffic volumes on congested 

facilities

`Real-time, multimodal traveler information to 

induce In-route mode shift

`Promotion of TDM at major trip generators in 

ATM corridors

Finally, an overall approach for integrating the two 

concepts is provided. It includes an overview of the 

integrated demand management under development 

in the United Kingdom.
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 5

[ ATM | TDM ]

At first glance, ATM and TDM appear to be 

complementary but unrelated concepts. 

ATM is about efficiently moving vehicles 

during the most congested times and in the 

most congested locations using a host of real-time 

management techniques, including ramp metering, 

variable message signs, speed harmonization, and 

even use of the hard shoulder as an auxiliary lane. 

TDM, at least traditionally, is about getting commuters 

to use alternatives to driving alone to work. ATM works 

with the congested facility to move vehicles most 

efficiently. TDM works with employees, employers, 

and others to shift commute modes of commuters. 

But the two concepts can come together in an obvious 

way when viewed as a holistic approach. This approach 

was first revealed to the international scanning study 

teams by the Dutch Ministry of Transport during their 

visits to the Netherlands. The conceptual framework, 

as proposed by the Dutch and modified for U.S. 

audiences, is shown in figure 1.

How Actively Managing Traffic and

Travel Demand Relate:

Dutch Model of Travel and Traffic Management

Figure 1. Dutch model of travel demand and traffic management.

n Traffic Management

 Demand Management

n Traffic Management/Demand Management

Traffic Incident 

Management

Lane Control 

System

Transportation 

Management 

Center

Ride-Matching 

Program

Travel

Demand

Traffic

Demand

Network

Demand

Route and

Time

Choice

Lane

Choice

Mode and 

Destination

Choice
[ ATM | TDM ]

At the heart of the conceptual framework is the need to 

understand the difference between travel demand management and traffic management. In its most rudimentary 

form, travel demand management seeks to influence 

travelers before the decision on whether and how to 

use the car is made and traffic management seeks 

to manage vehicles once these decisions are made.

Figure 1 shows the need to integrate travel demand 

and traffic management into a larger framework of travel 

choices and congestion-reduction techniques. These 

choices begin with consideration of overall travel demand 

and work their way through traffic demand and network 

demand. The strategies shown on the right side of the 

figure are not exhaustive and are meant to illustrate the 

kinds of strategies that focus on traffic management, 

travel demand management, or both. The transportation 

management center often serves as the coordinator 

among strategies. However, the key to the illustration is 

that it shows differences between types of demand and 

how offering choices can influence these demands. Each 

set of demands and choices is discussed below.

Stage One:

Travel Demand and Mode and Location Choice

This overall demand can be modulated by influencing 

travelers’ choices on whether to travel, which mode to 

use (car or other mode), and where to travel (destination). Many techniques can be applied at this stage of the 

framework to reduce overall travel demand by car. This 

might include incentives to use higher occupancy modes 

(e.g., carpool, vanpool, transit) or nonmotorized modes 

(bicycling, walking). It might include programs to encourage working or shopping at home (addressing whether to 

travel) or to reduce trip lengths or overall vehicle miles of 

travel (by combining trips or shopping or working closer 

to home). Of course, congestion pricing has been proven 

as an effective means to reduce travel demand by 

inducing mode shift and reducing peak travel overall. 

This stage involves influencing travel demand before the 

decision to drive (particularly alone) is made. Measures 

to influence travel mode and destination have the ability 

to reduce overall traffic volumes on the highway network 

and, when properly targeted, can reduce traffic volumes 

on key congested facilities during critical times of the day. 

The success of TDM initiatives, implemented during and 

as an integral part of highway reconstruction projects, 

provides solid evidence of the ability to manage traffic 

demand to reduce overall traffic volumes.

Stage Two:

Traffic Demand and Route and Time Choice

Once the amount of vehicle traffic demand is known, 

traffic can be influenced before it impacts the congested 

Travel Demand Management 

During Highway Reconstruction

During the 2002 reconstruction of U.S. 101 over 

the Cuesta Grade in San Luis Obispo County, 

CA, several demand management strategies were 

implemented to mitigate the impact of the roadwork 

on commuters. These measures included additional 

peak period bus service in the corridor, vanpool 

subsidies, and subsidized fuel cards for carpools. 

An evaluation of the impact of the demand 

management program concluded that the 

combination of measures eliminated 310 cars per 

day from the facility and about 8,000 miles of vehicle 

travel by raising overall vehicle occupancy from 1.206 

to 1.266. The daily cost to take each car off the road 

was estimated at $7.50.

These reductions contributed to an overall perception 

by the traveling public that the reconstruction project 

was less disruptive than originally feared.

6

Source: michael strauch, 2005
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 7

[ ATM | TDM ]

corridor and/or time period. This is primarily via measures 

to influence time and route choice. In other words, once 

travelers have decided to use their cars, can they be 

influenced to change the time of day they travel to avoid 

the most congested period, or can they be encouraged to 

seek alternate routes that might be less congested? These 

choices can also reduce the volume of vehicles using and 

impacting congested facilities—those facilities that might 

be most ripe for active traffic management. Congestion 

pricing can also influence the time of day or route that 

a commuter or other traveler chooses. Most highoccupancy toll lane projects in the United States increase 

the price of using the facility based on time of day and/or 

congestion levels. This has the impact of moving travelers 

to the shoulders of the peak period or even creating 

a route or mode shift to parallel facilities or to public 

transit or other less costly modes, such as carpooling.

Stage Three: 

Network Demand and Lane Choice

Once travelers make the decision to use their cars and 

travel on a given facility, network demand has been 

determined and the final choice that can be influenced 

is the lane travelers use on a road segment (and how 

each lane is used). The concept of influencing lane 

choice, rather new to the United States, is at the core 

of active traffic management. Examples include the use 

of the hard shoulder as a travel lane and dynamic lane 

controls. In several European countries, the hard shoulder 

is used during congested periods as a travel lane, with 

safety issues addressed by active monitoring and incident 

management. However, speeds are reduced on all lanes 

to maintain safe operation of the facility. In this manner, 

strategic capacity is added only when needed. Lane 

choice can also be actively managed during incidents by 

slowing cars upstream of the incident and moving them 

into unaffected lanes. Overhead speed and information 

displays, coupled with real-time monitoring, help by 

showing motorists the reason for the slowing of traffic 

upstream. (In figure 2, traffic in Germany is slowed from 

120 to 100 kilometers per hour (km/h) and trucks are 

prohibited from passing. The sign in figure 3 slows 

traffic to 60 km/h because of fog).

 On the right side of the Dutch model are examples of 

congestion management strategies that can be applied to 

manage travel demand, overall traffic, or a given facility. 

By no means is this exhaustive of the possible measures. 

Instead, it illustrates that while some strategies focus only 

on traffic management, such as lane controls, and others 

on demand management, such as ride-matching, some 

measures address both, such as incident management. 

Incident management can include active intervention 

on the facility, but it can also include real-time travel 

information to warn motorists before they ever get 

into their cars. The central coordinating function for 

all these measures is shown as the transportation 

management center that operates the facilities.

Therefore, while active traffic management can 

dramatically improve the efficient throughput and 

effective capacity of congested facilities, travel demand 

measures (aimed at mode, location, time, and route) 

can reduce overall traffic volumes entering the facility, 

improving the overall situation. These two concepts, 

when viewed in a holistic, integrated framework, can 

combine to better address congestion before it occurs 

and mitigate the impacts during congested periods.

Figure 3. Sign to slow traffic because of fog.

Figure 2. Overhead display in Germany.

Source: Straßen.NRW Source: Straßen.NRW
8

[ ATM | TDM ]

F

HWA’s consideration of the ATM and TDM 

concepts comes in part from two International 

Technology Scanning Program reports: Active 

Traffic Management: The Next Step in Congestion 

Management (FHWA-PL-07-012) and Managing Travel 

Demand: Applying European Perspectives to U.S. 

Practice (FHWA-PL-06-015).

The reports cover many of the same topics, including 

ATM, traveler information, and operational strategies to 

address congestion, and both refer to the Dutch model 

in lessons learned from the strategies observed. Both 

comment on the European emphasis on customer 

orientation in developing solutions and managing the 

system. But each report comes at congestion management from a different perspective. Understanding the 

definitions of ATM and TDM included in the scan reports 

can help clarify these complementary perspectives:

Active traffic management is the ability to 

dynamically manage recurrent and nonrecurrent 

congestion based on prevailing traffic conditions. 

Focusing on trip reliability, it maximizes the 

effectiveness and efficiency of the facility and 

increases throughput and safety. This approach 

consists of a combination of operational strategies that, when implemented in concert, fully 

optimize the existing infrastructure and provide 

measurable benefits to the transportation 

network and motoring public.

The operational strategies included in ATM are 

enumerated in table 1, along with the generalized 

benefits derived from each. For a more detailed 

description of each ATM strategy and examples from 

Europe, see the scan report at http://international.

fhwa.dot.gov/pubs/pl07012.

This definition of ATM focuses on vehicle trip reliability 

and optimal operations to maximize vehicle throughput. 

Its focus on the traveler is geared to providing travel 

time savings and greater reliability of travel times. 

As stated in the ATM scan report, organizations that 

have implemented ATM projects report the following 

measurable benefits:

`Increase in average vehicle throughput of 3 to 

7 percent

`Increase in overall capacity of 3 to 22 percent

`Decrease in primary incidents of 3 to 30 percent

`Decrease in secondary incidents of 40 to 50 percent

`Overall harmonization of speeds

`Increase in trip reliability

Integrating ATM and TDM:

Definitions and a New Perspective

Managing Travel Demand:

Applying European Perspectives to U.S. Practice

Active Traffic Management:

The Next Step in Congestion Management 
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 9

[ ATM | TDM ]

Reliable travel is at the heart of the TDM definition as well:

Managing travel demand is about providing 

travelers, regardless of whether they drive alone, 

with travel choices, such as work location, route, 

time of travel, and mode. In the broadest sense, 

demand management is defined as providing 

travelers with effective choices to improve travel 

reliability. 

Another definition of TDM, from the FHWA report Mitigating Traffic Congestion: The Role of Demand-Side Strategies (FHWA-HOP-05-001), defines it as better balancing 

the need to travel a particular route at a particular time 

with the capacity of available facilities to efficiently handle 

this demand. Influencing the need to travel is the purview 

of TDM, while efficiently handling vehicle demand is the 

focus of ATM.

The U.K. Highways Agency Influencing Travel Behavior 

(ITB) program aims at ”tackling congestion by providing 

access to information that enables people to make 

smarter travel choices.” 

The ITB process is shown in figure 4 on the following 

page (note: carsharing is the U.K. term for carpooling).

For a more detailed description of TDM strategies used 

throughout Europe, see the scan report on managing 

travel demand at http://international.fhwa.dot.gov/links/

pub_details.cfm?id=541. For U.S. examples, see the report 

on demand-side strategies at http://ops.fhwa.dot.gov/

publications/mitig_traf_cong/index.htm#toc.

In the United Kingdom, the Department for Transport 

campaign to encourage sustainable travel (means of travel 

that are less harmful to society, the environment and, 

ultimately, the economy) is called the Smarter Choices 

program. In its report on the program, Smarter Choices: 

Changing the Way We Travel, the U.K. government 

estimates that “soft” initiatives (e.g., not pricing or ATM) 

to influence mode, location, time, and route choice could 

reduce traffic nationwide by 2 to 11 percent, depending 

on the intensity and breadth of their application.

The U.K. government, along with other visionary nations 

such as the Netherlands, has recognized the need to 

Table 1. ATM strategies and potential benefits.

Source: FHWA
10

[ ATM | TDM ]

integrate TDM and ATM. The overall mission of the 

Highways Agency is “safe roads, reliable journeys, 

informed travelers.” As part of the reliable journeys 

objective, the Highways Agency is promoting two major 

initiatives, ATM (along with access management and 

high-occupancy vehicle lanes) and ITB. These concepts 

come together in the integrated demand management 

scheme being developed for the reconstruction and future 

operation of the M25 around London. More on this 

proposed integration process is at the end of the primer.

The need to integrate TDM and ATM should now be 

clear. The ability to simultaneously reduce demand and 

manage traffic on congested roads is a win-win proposition. If TDM reduces overall traffic volumes on a road and 

increases person throughput via alternative modes and 

ATM increases the capacity of the facility and maximizes 

vehicle throughput, the combined strategy should be a 

wise course of action.

However, simultaneously managing demand for and 

managing traffic in a given corridor requires careful 

planning and management. In a word, it takes an integrated approach. This approach is discussed after five 

examples of ATM and TDM integration are presented.

Figure 4. Influencing travel behavior process.

Source: Highways agency

Source: 

Department for Transport

Avoiding future congestion

Engage with the planning process

Encourage sustainable

development through the

planning process

Tackling current congestion

Identify congestion hotspots

Engage with regional stakeholders

Analyze existing infrastructure

Carry out travel surveys

Consider opportunities

Walking “Smart travel choices” and 

other initiatives Carshare

Cycling Access management Personalised journey 

planning

Public transport Travel plans Traffic information

Web-based journey 

planning Transport Direct Web site Car clubs

Bus priority Lanes Carsharing lanes Park and ride

Reduced congestion
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 11

[ ATM | TDM ]

New Partnerships for Integrating ATM and TDM in 

Congested Areas

Because the organizations that plan and manage demand 

management strategies are often different from those 

that manage traffic in a given corridor or area, new 

partnerships—or at least a new coordination mechanism—

may be needed to proactively integrate the concepts into 

one program. In the United States, it is often the metropolitan planning organizations, municipalities, or special 

purpose entities that manage TDM programs and initiatives. State departments of transportation operate the 

highway system, including managing day-to-day traffic. 

A third set of players is service providers, such as transit 

operators or traveler information vendors.

An example from the Netherlands shows an innovative 

partnership between government and business and 

among various components of government to maintain 

accessibility in The Hague/Rotterdam region, a congested 

area vital to the regional, national, and pan-European 

economy.

Bereik!, which means “reach” 

in Dutch, is the name of a new 

partnership in The Hague/

Rotterdam region, one of the most 

congested areas in Europe. The 

majority of highways in the region 

are actively managed (dynamic 

traffic management, using the 

Dutch terminology). 

Bereik! is a partnership of the 

Ministry of Transport’s South 

Holland district office, the South 

Holland Province, the metropolitan 

district, and the cities of The Hague 

and Rotterdam. Bereik! also works 

closely with consumer groups, 

such as the auto club and bicycle 

federation, and business, through 

the Confederation of Netherlands 

Industry and Employers. 

The mission of Bereik! is to 

improve accessibility in The Hague/

Rotterdam region. It seeks to fulfill 

this mission by concentrating on 

four thematic areas: 1) dynamic 

traffic management (e.g., ATM) 

that contributes to better and 

more predictable travel times, 2) 

reconstruction management and 

mitigation, 3) mobility management 

(e.g., TDM), and 4) leisure travel 

(serving tourists and visitors). To 

manage travel demand, Bereik! 

has staff dedicated to working 

with employers, developers, and 

commuters to seek alternatives to 

driving alone on the congested 

system. One innovative program 

of Bereik! is the Mobility Broker. 

Bereik! was instrumental in forging 

an agreement (the Rotterdam 

regional mobility covenant) 

between government and business 

to reduce the number of cars on 

the regional highway system by 5 

percent in 3 years and by 20 percent 

on the A15 motorway to the Port of 

Rotterdam during reconstruction.

Bereik! is a unique partnership 

to encourage planners, operators, 

managers, businesses, and users of 

the road system to all work together. 

It has resulted in a more holistic 

approach to managing traffic by 

integrating ATM, TDM, and 

related approaches.

Examples of ATM and TDM Integration

Bereik!—The Hague/Rotterdam, Netherlands

Source: WSDOT
12

[ ATM | TDM ]

Enhanced Travel Alternatives in Actively 

Managed Corridors

Another way to reduce the volume of cars on a congested 

facility is to offer alternatives to driving alone during the 

most congested periods. One strategy is providing new 

or enhanced commute alternatives. This might involve 

the promotion and formation of vanpools serving the 

corridor, new bicycle paths in the corridor, or new or 

improved public transit services. A good example of a 

concrete plan to integrate ATM with two key demand 

management strategies, pricing and improved public 

transit, is the State Route 520 corridor in the Puget 

Sound region of Washington State.

Puget Sound Region, 

Washington

The U.S. Department of 

Transportation’s Urban Partnership 

Agreement (UPA) program 

includes implementation of four 

Ts—tolling, technology, transit, 

and telecommuting/TDM. One 

recipient of UPA funding is the 

Puget Sound region, which will 

focus on the SR 520 corridor that 

links downtown Seattle to the 

Eastside area of Lake Washington. 

The Lake Washington Urban 

Partnership integrates all four Ts. 

SR 520 will implement variable 

time-of-day tolling for all lanes to 

manage congestion and contribute 

early revenue to help fill the 

funding gap for the replacement 

of the floating bridge. Technology 

will be installed on SR 520 and 

Interstate 90, a facility parallel to 

SR 520, to actively manage the 

corridor in one of the first largescale implementations of ATM in 

the United States. It will include 

most of the techniques explored in 

the ATM scanning report: speed 

harmonization (variable speed 

limits), queue warning, lane control, 

and advanced traveler information. 

Another key component is the 

addition of substantial transit 

service in the SR 520 corridor. New 

enhancements include 45 additional 

buses, real-time travel signs at transit 

stations, and improved park-andride facilities. Drivers will also be 

encouraged to explore vanpools, 

carpools, or telecommuting as 

alternatives to driving alone. 

Working with existing networks of 

large employers, outreach activities 

will outline the many options 

available to drivers of this newly 

enhanced corridor. (See “TDM 

Strategies in the SR 520 Corridor.”)

Source: Robert Hull, 2005Source: WSDOT

Lake Washington Urban Partnership—SR 520
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 13

[ ATM | TDM ]

Incentives to Reduce Traffic Volumes on 

Congested Facilities

While ways to manage demand on a congested facility 

include controlling access (via ramp metering, for 

example) or lowering vehicle volumes by shifting travelers to alternative modes, an innovative strategy that 

combines pricing, commute alternatives, and traffic 

management is called “rush hour avoidance.” This 

involves inducing regular travelers (e.g., commuters) to 

defer or eliminate travel on a congested roadway during 

the most congested times. In 2001, the U.K. Highways 

Agency distributed a leaflet urging travelers to avoid the 

M25 motorway around London during rush hours. More 

recently, a successful pilot in the Netherlands provided 

interesting and compelling results on the impact of 

incentives to induce rush hour avoidance.

A research project on rush hour 

avoidance (or “spitsmijden” in 

Dutch) involving the Dutch 

Ministry of Transport, several 

universities, consultants, and 

Bereik! was implemented in 2006. 

This involved piloting an incentive 

program to induce travelers to 

avoid the A12 motorway between 

Zoetermeer and The Hague during 

the rush hour period of 7:30 to 

9:30 am. Participants were offered 

a financial incentive of about US$4 

per day (€3) (or, alternatively, a 

chance to win a smart phone) to 

avoid traveling on the facility during 

this time. Cars were fitted with 

transponders to record where and 

when participants traveled. The 

number of participants traveling 

during the peak congested hours 

was halved during the experiment. 

While some who avoided the peak 

hours shifted to carpools, transit, 

and cycling (the opening of a new 

rail service in the corridor was 

delayed), the greatest proportion 

simply shifted the hours they 

traveled, most to before 7:30 a.m. 

The success of the experiment is 

now being replicated on another 

stretch of the A12 to Gouda. Even 

public transit operators are using the 

program to shift riders outside the 

overburdened peak period.

Rush Hour Avoidance Incentive—The Hague, Netherlands

Source: Rijkswaterstaat
14

[ ATM | TDM ]

Real-Time Multimodal Traveler Information to Induce 

In-Route Mode Shift

Good traveler information can have many impacts on 

travel decisions, including mode, location, route, and time 

choices. The FHWA primer Managing Demand Through 

Travel Information Services (FHWA-HOP-05-005) is a 

useful source for details and U.S. case studies. Traveler 

information can be delivered pretrip, near-trip, or on-trip. 

Pretrip information can induce travelers to use transit or 

bicycles for a particular trip. Near-trip information can 

influence the time of travel or routing. Predicted travel 

times can help travelers schedule activities for less 

congested periods. On-trip (en route) information 

can influence travel route (diversion around incidents 

or backups) or even en route mode choice.

Cologne, Germany, 

and San Mateo County, 

California

Innovative pilot projects in Germany 

and California offer drivers 

comparative times for traveling 

the road they are on or diverting 

to a transit station, parking, and 

continuing by train or bus. In 

Cologne, Germany, a travel time 

display sign has been placed on a key 

arterial in the city center. The sign 

displays the real-time travel times 

to the Neumarkt square by car and 

public transport. It is intended to 

induce a diversion to a park-and-ride 

facility at an adjacent soccer stadium 

served by a tram line. The travel time 

display shows the departure time 

of the next tram and the real-time 

minutes to the Neumarkt square. 

This allows drivers to avoid the most 

congested part of their commute if 

the transit travel times are favorable. 

Likewise, U.S. 101 in San Mateo 

County, CA, includes comparative 

travel times using regular variable 

message signs. Real-time highway 

travel times are posted to 

downtown San Francisco, along 

with scheduled travel times for 

the Caltrain commuter rail service 

from two major stations with parkand-ride facilities (Millbrae and 

Redwood City). Researchers at the 

California Center for Innovative 

Transportation at the University 

of California, Berkeley—along 

with the California Department 

of Transportation (Caltrans), 

Caltrain, and the San Mateo County 

Transportation Authority—are 

working to integrate real-time train 

travel times. Real-time, multimodal 

information is a key component of 

Caltrans’ multimodal integrated 

corridor management approach.

Source: CCIT

Source: Schreffler

Comparative Travel Times for Car Versus Train
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 15

[ ATM | TDM ]

Promotion of TDM at Major Trip Generators

Another way to reduce overall vehicle volumes on a 

congested facility is to work with large trip generators, 

such as large employers, business parks, sporting and 

entertainment venues, recreation sites, shopping centers, 

and even residential areas. These trip reduction programs 

can target employees and visitors of these sites who use 

the congested facility regularly.

The Lake Washington Urban Partnership, planned for SR 

520 in the Puget Sound region, provides an example of 

a proposed integrated approach to managing demand 

at trip generators while actively managing traffic on the 

adjacent facility. 

Puget Sound Region, 

Washington

The SR 520 corridor is the 

planned site for congestion pricing, 

ATM, transit enhancements, and 

supportive TDM strategies as part 

of the Lake Washington Urban 

Partnership effort (see “Lake 

Washington Urban Partnership—

SR 520”). The plans for 

integrating TDM into the corridor 

management scheme included the 

identification of major geographic 

areas that serve as key origins and 

destinations for SR 520 commuters 

and other travelers. This included 

not only major employment centers 

(called Growth and Transportation 

Efficiency Centers) such as 

Redmond, Bellevue, and downtown 

Seattle, but also major travel 

generators such as the University 

of Washington. 

Plans for enhancing demand 

management efforts in the corridor 

include three key areas:

Vanpooling—Facilitate 

the anticipated growth 

in vanpooling resulting 

from tolling, technology 

enhancements, and transit 

improvements.

Telecommuting—Target 

outreach efforts and technical 

assistance to local employers 

in an enhanced cross-lake 

telecommuting program 

to induce alternative work 

arrangements, including 

telecommuting, flexible 

scheduling, and compressed 

work weeks.

Education and awareness—

Include specific information 

on travel alternatives to driving 

alone, the incentives and 

advantages for doing so, and 

the TDM partners who provide 

these services in the employer, 

commuter, and resident 

outreach materials for the 

Lake Washington Urban 

Partnership project. 

Regional stakeholders are 

consciously integrating TDM 

strategies with ATM, pricing, and 

transit enhancements to create a 

holistic solution to congestion in 

the SR 520 corridor.

Source: kingcounty.gov

TDM Strategies in the SR 520 Corridor
[ ATM | TDM ]

A

s the introduction states, the United 

States and Europe currently have 

no examples of a truly integrated 

approach to ATM and TDM with 

concrete results. This is largely because of 

the relative newness of ATM, the perceived 

lack of solid evidence on TDM, and the 

absence of comprehensive examples of 

integration. However, experience from the 

European scanning studies coupled with 

a review of the examples included in this 

primer suggest several components that 

should be present to effectively integrate 

ATM and TDM into a holistic solution to 

congestion on a given corridor:

`A policy framework that equally embraces 

both categories of strategies, ATM and TDM

`A customer orientation that focuses on 

travelers as much as their cars

`Flexible funding and project selection 

criteria that are not biased toward one 

solution or strategy

`Forethought and planning on how to 

integrate, fund, implement, operate, 

monitor, evaluate, and adjust the 

integrated program

`A careful understanding of the varied 

traveler markets that use the congested 

facility and that can be targeted by 

various TDM and ATM strategies

`Specific but related performance targets 

on realistic demand reduction and 

efficiency improvements 

Proposed Approach for Integrating ATM 

and TDM Into a Holistic Program

Integrated Demand Management for the 

M25 Around London

The Highways Agency is developing a new approach to addressing 

congestion on its most critical facilities: integrated demand 

management (IDM). IDM combines many of the ATM strategies 

discussed in the scanning report with the influencing travel 

behavior initiatives that mirror many of the TDM strategies, 

including the development of specific strategies (called travel 

plans) to reduce car trips at major travel generators.

The IDM concept is being applied to the reconstruction and 

widening of the M25 motorway around London. The Highways 

Agency describes IDM as “a holistic approach based upon making 

best use of the existing road-space and locking in the benefits 

of widening.” The philosophy behind IDM is to maximize the 

efficiency of the facility using ATM and the effective life of the 

improvement by reducing overall demand for its use.

According to the Highways Agency, IDM takes a corridor 

approach in which smarter choices measures (TDM) are 

deployed over a wide area to support onroad management 

measures, including ATM, access management (e.g., ramp 

metering), priority lanes for carpools and buses (e.g., HOV 

lanes), traveler information, incident management, and 

wide-area traffic management to integrate national 

and local traffic management systems.

16
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 17

[ ATM | TDM ]

`Transportation management centers that view their 

charge as managing both traffic and travel demand

`New partnerships to coordinate the implementation

of both ATM and TDM in a given corridor or subregion

If adopted by agencies responsible for congestion 

management, these recommendations could go far 

to create the foundation for this holistic approach to 

congestion mitigation, mobility, accessibility, and 

travel time reliability.
[ ATM | TDM ]

18

T

his primer started with the premise that 

congestion management has two—perhaps 

equally—important components: traffic management and travel demand management. The first 

seeks to manage vehicles efficiently on a congested 

facility and the second seeks to reduce overall volumes 

using the facility during congested periods. This simple 

and intuitive distinction can radically change the perspective on the range of mitigation strategies that can be 

planned and implemented for congested corridors. 

Two sets of distinct but complementary strategies can 

be used simultaneously on a congested roadway: active 

traffic management and travel demand management. 

This primer has provided a conceptual foundation for 

understanding the traveler choices that can be influenced by ATM and TDM and the stages in the travel 

decision process when various strategies can be used. 

For example, strategies to induce mode shifts or eliminate the need to travel can reduce overall traffic volumes 

in a corridor and maximize person throughput. Strategies 

to shift the travel time or route to less congested conditions can impact the ability to reduce delay and maximize travel-time reliability. Finally, strategies to influence 

motorists upstream of traffic jams to modulate their 

speed and efficiently move cars into optimal travel lanes 

(including the hard shoulder) can effectively increase the 

capacity of the facility and maximize vehicle throughput.

However, to realize the greatest mobility and accessibility 

benefits from these congestion reduction strategies, ATM 

and TDM must be better integrated into the planning, 

management, and operation of key facilities in congested 

corridors. This primer has provided five examples of this 

integration. By themselves, ATM and TDM can accomplish much to address urban transportation policy 

objectives. U.K. estimates are that ATM can increase 

effective road capacity by 3 to 22 percent on a facility 

that is actively managed and TDM (Smarter Choices) can 

reduce overall car travel by 2 to 11 percent. Together in 

an integrated fashion, ATM and TDM can provide holistic 

benefits that are clearly greater than the sum of the two 

sets of strategies when implemented as relatively 

separate programs.

Source: Highways Agency

Summary
Integrating Active Traffic and Travel Demand Management: A Holistic Approach to Congestion Management | 19

[ ATM | TDM ]

California Department of Transportation, Multimodal 

Integrated Corridor Management Workshop—Summary 

of Findings, www.dot.ca.gov/newtech/modal/micm/

summary_of_finding-micm_workshop-dec_2007.pdf.

Caltrain, “Caltrain Commute Times to Run on 101 Info 

Signs,” Caltrain News, July 2, 2007, www.caltrain.com/

news_2007_07_02_101_info_signs.html.

Department for Transport, Smarter Choices: Changing 

the Way We Travel, June 2005, www.dft.gov.uk/pgr/

sustainable/smarterchoices/ctwwt/.

ESTC, Cuesta Grade Transportation Demand Management Program Evaluation, prepared for the San Luis 

Obispo Council of Governments, Feb. 23, 2003.

Federal Highway Administration Congestion Pricing 

Primer Series:

Congestion Pricing—A Primer: Overview,

FHWA-HOP-08-039.

Lessons Learned From International Experience in 

Congestion Pricing, FHWA-HOP-08-047.

Technologies That Complement Congestion Pricing—

A Primer, FHWA-HOP-08-043.

Technologies That Enable Congestion Pricing—

A Primer, FHWA-HOP-08-042.

Federal Highway Administration, Office of International 

Programs, Active Traffic Management: The Next Step 

in Congestion Management, FHWA-PL-07-012, 

March 2007.

Federal Highway Administration, Office of International 

Programs, Managing Travel Demand: Applying European Perspectives to U.S. Practice, FHWA-PL-06-015, 

May 2006.

Federal Highway Administration, Office of Transportation 

Management, Mitigating Traffic Congestion: The Role 

of Demand-Side Strategies, FHWA-HOP-05-00, 

October 2004.

Frans Middelham, “Dynamic Traffic Management in the 

Netherlands,” Rijkswaterstaat Traffic Research Center 

(AVV), presentation to FHWA Managing Travel Demand 

Scanning Study Team, June 27, 2005.

Highways Agency, “Integrated Demand Management,” 

www.highways.gov.uk/knowledge/18297.aspx.

Highways Agency, “Tackling Congestion by Influencing 

Travel Behaviour,” www.highways.gov.uk/knowledge/ 

9561/aspx.

National Audit Office, Tackling Congestion by Making 

Better Use of England’s Motorways and Trunk Roads, 

report by Comptroller and Auditor General, Nov. 26, 

2004.

Puget Sound Regional Council, “Draft Methodology for 

Lake Washington Urban Partnership TDM Analysis,” 

Travel Demand Management Analysis Working Group, 

2010.

Spitsmijden, Effects of Rewards: Spitsmijden Summary, 

April 2007, www.spitsmijden.nl/old/resultaten/

Rapport_publiek(ukdef).pdf.

U.S. Department of Transportation, Seattle 

(Lake Washington) Urban Partnership Agreement, 

www.upa.dot.gov/agreements/seattle.htm.

Resources


OFFICE OF INTERNATIONAL PROGRAMS

FHWA/US DOT (HPIP)

1200 New Jersey Ave., SE

Washington, DC 20590

Tel: (202) 366-9636

Fax: (202) 366-9626

international@fhwa.dot.gov

www.international.fhwa.dot.gov

Publication No. FHWA-PL-11-011

HPIP/01-11(3.5)EW