Assessment of the seismic risk associated with small earth dams: a simplified approach

Small earth dams are characterized by a reduced height of the retaining structure and by a limited reservoir volume of water. They are often located along slopes close to populated areas, therefore the risk associated with their potential rupture could be considerable. Also for this reason, the evaluation of their seismic vulnerability is of paramount importance for Civil Protection purposes. In addition, the usual lack of technical information represents a significant further challenge. In this regards, a simplified methodology based on a reduced number of parameters was required for vulnerability assessment studies. A simplified procedure was developed to systematically classify a large number of small earth dams. The proposed methodology is based on the compilation of data-sheets that lead to a preliminary classification of structures in terms of their associated seismic risk. The application of this procedure to about a hundred earth dams in the Piedmont region allowed identifying the most critical structures, which require a priority in the planning of further investigations and analyses.