Stream Instability, Bridge Scour, and Countermeasures: A Field Guide for Bridge Inspectors

FHWA Publication No. FHWA-NHI-08-0106. February 2009. Explains the behavior of rivers in order to recognize changing conditions associated with unstable streams or scour at bridge foundations that may threaten the stability of the bridge. Provides tips and guidance on what to look for with regard to both stream instability, including lateral instability, degradation, and aggradation, and scour at bridges, including contraction scour, pier scour, and abutment scour. Also covered are plans of action and countermeasures, such as monitoring, flood watches, bridge closures, and river training countermeasures.

This manual is intended for use by Federal, State, and local highway hydraulic, structural, and geotechnical engineers as well as bridge inspectors responsible for maintaining the integrity of highway bridges against possible hydraulic-related problems. Consultants who perform bridge engineering would find this useful.