Debit Banjir Rancangan DAS Selabung dengan HSS Nakayasu

Abstract

Knowledge and analysis about flood discharge in Selabung watershed is used as spillway planning. Selabung watershed with Selabung River as the main river and 71.29 km long. Flood’s controlling in spillway is needed especially when water level almost reachers the maximum discharge. The purpose of this study was to determine the design flood discharge in Selabung watershed for the 100 year return period. The primary data in this study is morphological observation data and the secondary datas are rainfall data from 2001 to 2014, topographic data, land use, and river cross-section data. The calculation of rainfall average for three rain stations used Poligon Thiessen method. From the calculation of design flood discharge for 100-year return period using The Nakayasu Synthetic Unit Hydrograph, the discharge is 36.89 / s.