A guidance manual for assessing scour potential using the South Carolina bridge-scour envelope curves

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations of bridge scour in order to better understand regional trends of scour within South Carolina. The studies collected historic-scour data at approximately 200 riverine bridges including measurements of clear-water abutment, contraction, and pier scour, as well as live-bed contraction and pier scour. These investigations provided valuable insights for regional scour trends and yielded bridge-scour envelope curves for assessing scour potential associated with all components of scour at riverine bridges in South Carolina. The application and limitations of these envelop cureves were documents in three reports, Each repoort addresses different components of bridge scour and this, there is a need to develop an integrated procedure for applying the South Carolina bridge-scour envelope curves. To address this need, the U.S. Geological Survey and the South Carolina Department of Transportation initiated a cooperative effort to develop an integrated procedure and document the method in a guidance manual. In addition to developing the integrated procedure, field data from other investigations outside of South Carolina were used to verify the South Carolina bridge-source envelope curves.