Submitted to: Workshop Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2002
Publication Date: May 17, 2002
Citation: Hanson, G.J., Temple, D.M. 2002. Embankment research. CD-ROM. Proceedings of the 1st IMPACT Workshop, HR Wallingford, UK. Technical Abstract: Aging of the US watershed dams and the move to rehabilitate them has raised new questions related to overtopping of earth embankment dams. Changes in watershed land use and filling of the sediment pools may in some cases combine to cause overtopping of structures by floods that would have been contained at the time of reservoir design. Changes in land use in the downstream floodplain may result in the need for the reservoir to contain larger floods than those for which it was originally designed. Analysis of these conditions suggests the need for re-evaluation of the traditional assumption that overtopping of an un-reinforced earth embankment always results in failure. Research is presently underway at the United States Department of Agriculture (USDA), Agricultural Research Service (ARS), Plant Science and Water Conservation Laboratory (PSWCRL), in Stillwater, Oklahoma, with the goal of providing a means of evaluating the performance of overtopped earth embankment dams protected only by a vegetal cover. This research will provide the basis for prediction of the extent of overtopping that may be withstood without breach, the timing of the breach when failure does occur, and the hydrograph resulting from a failure. Preliminary results of the research confirm that these performance characteristics are strongly influenced by the nature and uniformity of the vegetal cover, the properties of the embankment materials, and the presence of berms and/or unprotected areas of the downstream toe.