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A region’s social and economic fabric is weaved through intricate movements of people, goods and

services. Roadways are the capillaries, veins, and arteries of life, carrying the pedestrians, bicycles, cars,

buses, and cargo trucks to their intended destinations. In the conventional approach to the planning of

road systems, the growth of travel demand is largely addressed by adding capacity, including widening

existing roads and building new roads. However, every time capacity is added, additional traffic is

generated, especially in situations where traffic demand controls are minimal or absent. The extent of the

induced traffic generated by road infrastructure improvements varies from place to place but the fact that

the potential of higher speeds offered by new capacity results in more trips, longer trips, and redistributed

trips has been fairly well documented (Goodwin, 1996; Hills, 1996; Hansen and Huang, 1997; Noland,

2001; Cervero, 2002). The additional traffic generated is also, in part, attributable to new activities that

locate on these new and upgraded roads (Ewing and Lichtenstein, 2002). In a matter of time, therefore,

the road returns to being congested and unsafe, demanding capacity expansion.