Mechanics of Overflow Erosion on Embankments. II: Hydraulic and Design Considerations

Abstract

This is a companion report to “Mechanics of Overflow on Embankments, Part I - Research Activities.” It discusses the hydraulics of water flowing over an embankment which is considered to be the basis for understanding the erosion process during overtopping events. The behavior of embankments that are subjected to overflow flood events are reviewed. Further information is developed based on results of research and actual case histories of embankments dams, levees, and roadways that have experienced overtopping. This report also provides information on the various protection systems that have been developed to prevent erosion of dam, roadway and levee embankments during overflow, including those tested in Part I. Case histories of several cost effective modifications made to embankment dams to permit overtopping are also discussed. The knowledge gained from using these hydraulic and design considerations provides the engineer and dam owner further information in the development of cost effective measures that allow embankments to pass extreme flood events without breaching.