CHANNEL CHANGES ANALYSIS IN SAMBELIA BASIN DUE TO DEBRIS FLOW

• Main Author: Erma Suaranu, Baiq
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/44189
• Institution: Institut Teknologi Bandung

DAS Kokok Sambelia is Sub-Basin Menanga in Sambelia District, East Lombok. Based on the geographical state of Sambelia district is a hazard prone area. Sambelia subdistrict is often hit by land landslides, typhoon, drought, floods, and volcano disasters. The most common disaster in the Sambelia,s sub-district is the flash flood caused by landslides that occurred in the upstream area then resulted in a flash flood that could damage the residents ' settlements. The results of the study based on the flow of the river before the delta in Sambelia basin, obtained the calculation of the value of Tg ?h < Tg ? < Tg ?d = 0.02 < 0.05 < 0.08 entered into a hyperconcentration flow type. The concentration of sedimentary debris CDs amounted to 0.3 ppm, with a stream correction coefficient of Fr = 0.1. Total sediment that occurred in Sambelia basin in the 5-year anniversary of 54482.232 m³ which is the total sediment result of debris. At minimum energy analysis the river obtained the smallest S value taken i.e. 1.906 x 10-3. There was a change in the flow of rivers in Sambelia, Labuhan Pandan and Kokok Semareng which is the 1st Order River in 2013, 2014, 2017 and 2018. These Rivers has the channel that comes down to the delta of DAS Sambelia and indicates that there is also a pile of sediment in its river channel.