Introduction - Road Traffic Congestion - page 5

In summary, the topic focuses on four key objectives:

1. To understand and address the factors that contribute to traf c congestion,

2. To understand the issues involved in quantifying urban traf c congestion,

3. To assess the impacts of congestion on urban and suburban mobility, access to
activities, network productivity, and environmental quality, and,
4. To provide congestion relief strategies that

increase traf cef ciency and

increase the use of alternative modes of transportation.

Each of these objectives is examined from a concise multi-disciplinary per-
spective using illustrations and techniques that provide for a broad, yet clear,
understanding of traf c congestion and its impacts, and that will describe adaptation

and mitigation strategies that are likely to provide congestion relief.

1.3 Overview of the Topic

The topic is organized into 24 chapters grouped into four parts:

—

3 ):
In addition to this chapter Part I includes Chap. 2 , “ How Transportation Tech-
nology has Shaped Urban Travel Patterns,

1. Part I Background (Chaps. 1 -

” and Chap. 3 , “ Historical Perspective of

Urban Traf c

congestion from historical and contemporary viewpoints. It shows how technology,
transportation technology in particular, has extended urbanized areas and traf

c Congestion. ” Chapter 2 examines urban development and traf

c

congestion. The chapter shows that urban traf c congestion is not only a current

phenomenon, but has existed in cities since ancient times. Chapter 3 shows how
growth in population, employment, motorization and vehicle miles since World
War II has contributed to the spread of congestion from the city center to the entire
metropolitan area.

2. Part II — Traf c Congestion Characteristics, Causes, and Consequences (Chaps.

4 13 ):

-

c congestion. They include the
concentration of travel demand in time and space (Chap. 5 ) ; the effect of growth in
population employment and car use, population density, and the lag between
roadway capacity growth and travel growth (Chap. 6 ) ; and the effect of bottlenecks
(Chap. 7 ). Chapter 8 describes the criteria and metrics used to describe and quantify
congestion; and Chaps. 9

Chapter 4 describes the underlying causes of traf

13 address the impacts of congestion on trip time and
reliability, mobility, accessibility,

-

traf c productivity, transportation costs, and

quality of life issues.
3. Part III — Congestion Relief Strategies (Chaps. 14 23 ) :

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Chapter 14 provides an overview of possible adaptive and mitigation strategies
for managing congestion. The chapter provides a framework for the various