Capturing System-wide Magnitude of Earthquakes’ Effects on Urban Traffic Networks

:Transportation networks are one of the most important lifelines, designated to support societies even–if not especially-in cases of emergency. Though, the design and operations of the road infrastructure in metropolitan areas is typically based on demand assumptions reflecting either guided or equilibrated conditions. Even in cases of evacuation network modeling and planning, the demand scenarios typically considered fail to reflect the public’s massive, sudden and abrupt response to the unexpected, as repeatedly reported in recent cases. The current paper offers possibly unique evidence of a system response on a significant nature-caused event and in particular that of the major earthquake in the metropolitan area of Athens, Greece, occurred in 1999. Detailed traffic data adequately covering Athens’ road network are presented and thoroughly analyzed such as to provide quantitative information on system-wide traffic patterns in cases of such major events. The results aim to contribute valuable information that may facilitate the preparation of authorities responsible for civil protection, especially related to transport planning in cases of emergency.