Seite - 1277 - in Book of Full Papers - Symposium Hydro Engineering

COMMISSION INTERNATIONALE DES GRANDS BARRAGES ------- VINGT-SIXIÈME CONGRÈS DES GRANDS BARRAGES Autriche, juillet 2018 ------- FORMAL INVESTIGATION OF LAHOR DAM, INDONESIA Teguh WINARI1, Kamsiyah WINDIANITA1, Didik ARDIANTO1, Fahmi HIDAYAT2, Raymond Valiant RURITAN3 1Research and Development Bureau, 2Deputy Director for Technical Affair, 3Director of JASA TIRTA I PUBLIC CORPORATION INDONESIA 1. INTRODUCTION Lahor dam is located in Malang Regency, East Java Province of Indonesia. It is one of the dams in Brantas watershed on the tributary of the Lahor River. Lahor dam was constructed in 1972 for adding capacity of Sutami hydropower. Not only provides great benefits, dam also creates a potential risk to neighboring populations, property, and the natural environment. Therefore, assessment and monitoring of the dam have to be carried out comprehensively and periodically. Formal investigation of Lahor dam aim to evaluate the dam condition during design and construction compare to recent. It is also including visual inspection, instrumentation and slope stability analysis, hydrology and geology condition, and sedimentation analysis. Based on those parameters, the condition of the Lahor dam was ready to be operated. 2. METHOD Formal investigation of Lahor dam consist of two stages: preliminary stage and advance stage. The former aims to collect all of the information about dam design, construction document, and dam record book (operating and maintenance). While there is an anomaly on the preliminary study, advance study must be carried out that are including re-evaluation of design document, construction method and material type, analysis of operation and maintenance document, and engineering analysis. 3. RESULT AND DISCUSSION 3.1. VISUAL INSPECTION Visual inspection activities include dam body and complementary building, water quality analysis in laboratory, monitoring of dam instrumentation, hydro mechanical equipment, and concrete structure condition on spillway and access 1277