Bridges (IMAGE) Stanford University Caption Of 35 bridge collapses analyzed, floods caused 13, erosion of sediments around bridge foundations -- scour -- caused 16, a hurricane caused 1 and other influences (such as waterborne or hydraulic debris) caused 5. Superimposed H denotes sites where a hurricane or tropical storm occurred and may have influenced bridge collapse. Area of circles is proportional to drainage area of bridge sites. Credit Flint, et al. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.