Page - 1112 - in Book of Full Papers - Symposium Hydro Engineering

COMMISSION INTERNATIONALE DES GRANDS BARRAGES ------- VINGT-SIXIÈME CONGRÈS DES GRANDS BARRAGES Autriche, juillet 2018 ------- IN-DEPTH SAFETY ASSESSMENT OF LARGE RUN-OF-RIVER HYDROPOWER PLANTS IN SWITZERLAND Dr. Sven-Peter TEODORI Dam Engineer, AF-CONSULT SWITZERLAND LTD Helmut STAHL Senior Dam Engineer, AF-CONSULT SWITZERLAND LTD SWITZERLAND 1. INTRODUCTION AND BACKGROUND Among the 1200 dams classified in Switzerland, 167 are large dams according to ICOLD standards. The Swiss Federal Office of Energy (SFOE) is entrusted with the overall supervision of the enforcement of the legislation, which comprises the development of the safety concept and dam safety requirements published in form of Guidelines. The SFOE is also entrusted with the direct safety supervision of the 217 largest dams in view of their impounding head, storage capacity and hazard potential for the population in the area downstream of the dam. These are categorized into 124 concrete dams, 66 embankment dams and 27 run-of-river hydropower plants. The latter are deemed to be in the interest of public safety mainly for their relevant storage capacity. With the new Dam Safety Legislation in Switzerland (2012), large run-of-river hydropower plants along main rivers became subjected to in-depth safety assessments under the direct supervisory authority of the SFOE based on the specific Enforcement Guideline of the Dam Safety Legislation (2015). The Swiss dam safety concept, apart from continuous surveillance, maintenance and emergency planning also entails such periodic in-depth safety assessments. This consists in a review of hydraulic and structural actions (static, flood and seismic) 1112