Traveler Response to Damaged Freeways and Transportation System Changes Following Northridge Earthquake

When four key freeways in Southern California were damaged on January 17, 1994, by the Northridge earthquake, state and local agencies implemented a variety of emergency measures to the transportation systems in damaged corridors to ensure some degree of mobility during reconstruction. Travelers who had used damaged routes were faced with a variety of travel choices, such as using primary roadway detours, ridesharing, diverting to other roads, using transit, avoiding travel, telecommuting, or changing time of travel. On the basis of comprehensive travel surveys, traffic monitoring, and data collection, it was determined that travelers responded in significantly different ways in each of the four damaged corridors. In the very heavily traveled 1-10 (Santa Monica) Freeway Corridor, even though primary roadway detours could only carry approximately 40 percent of normal freeway capacity, virtually all travelers still drove their automobiles because numerous parallel streets exist in this corridor as alternati...