University of California Transportation Center

Traffic congestion has reemerged in the 1980’s as a leading public concern. In metropolitan areas throughout the United States, reports about mounting traffic levels and daily tie-ups appear on a regular basis. Highway agencies and transit operators are castigated for failing to provide the facilities and services needed to assure a convenient commute. The agencies, in turn, point to funding cutbacks and escalating costs as barriers to action. Urbanists and demographers note that long-term trends toward decentralized development and increased participation in the work force have both contributed to congestion. Increasingly, angry citizens are blaming new development for the traffic problems and are pressuring local officials to either slow growth or find some other way to relieve the traffic loads.

Congestion problems are not, of course, a new phenomenon. For many decades, heavy traffic has been a fact of life in central business districts and on routes leading downtown. Today, however, in an increasing number of communities, the rush hour has become a two or three hour peak period, and congestion recurs mornings, midday, midevening, and on weekends as well. Heavy congestion is occurring in the suburbs as well as the city, both on local streets and on the circumferential highways that a decade ago provided for high speed travel.