Proceedings of the 5th International Conference on Scour and Erosion, held in San Francisco, California, November 7-10, 2010. Sponsored by the Geo-Institute of ASCE; Environmental and Water Resources Institute of ASCE; International Society for Soil Mechanics and Geotechnical Engineering. This collection contains 113 papers on scour and erosion, which constitute some of the most critical threats to maintaining infrastructure and quality of life throughout the world. As the human population expands, the responsibilities of engineers, scientists, and designers continue to increase. The demand for a creative approach to effective control of scour and erosion also becomes more pressing, requiring cross-disciplinary synthesis of information from the fields of hydraulic and geotechnical engineering. The papers presented in this book examine the scour and erosion of hillside, fluvial, estuarine, and coastal environments at the interface of water, soil, and rock. Topics include: bridge scour; erosion of soils; scour and erosion of dams and levees; scour of offshore platforms and underwater pipelines; numerical modeling; physical model tests; rock scour; case histories, management, and field studies; monitoring; countermeasures, stream stability, and erosion of slopes; and FHWA equations and design standards. This proceedings will be valuable to anyone working in the fields of geotechnical or environmental engineering