USDA-ARS HERU Embankment Erosion Research: Past, Present, Future

Authors: Hunt, Sherry; TEMPLE, DARREL - Retired ARS Employee; Tejral, Ronald

Submitted to: Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/30/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Although dams across the U.S. have an excellent safety record, dams do fail, and when they fail, life and property downstream are potentially at risk. Overtopping and internal erosion are the most common causes of embankment failures. The USDA-Natural Resources Conservation Service (NRCS) through the authorization of the USDA Small Watershed Program have provided technical and financial support for the construction of nearly 12,000 dams. Over half of these dams have reached the end of their planned service life. Some dams are at increased risk for failure due hydrologic changes and impairment of reservoir by sedimentation. To examine the breach and failure processes, USDA-ARS Hydraulic Engineering Research Unit scientists have conducted physical model studies to record and observe embankment breach processes that occur due to overtopping and internal erosion. Simplified algorithms to simulate dominant erosion processes such as failure of vegetation or riprap on the downstream face of the dam, headcut advancement, and breach widening have been developed based on large-scale laboratory tests. In partnership with the USDA-NRCS and Kansas State University, the algorithms have been incorporated in the Windows Dam Analysis Modules, WinDAM. Further enhancements of the model are expected to follow from research exploring erosion processes of zoned embankments and erosion and damage repair that may occur on complex geometries like the embankment groin and toe. This research will further augment the tools available for prioritizing dams for rehabilitation, improving flood warning systems, and developing emergency action plans and zoning regulations.