Assessment of sedimentation rates in the Way Seputih Watershed Area

Abstract

Way Seputih watershed is one of the important watersheds located in Central Lampung Regency and is a source of waters both agriculture and industry. The occurrence of floods that occur during the rainy season is due to reduced forest cover that is converted to agricultural land and settlements. In the Way Seputih River many sand mining activities will have implications for the sedimentation process at the downstream of the Way Seputih River. The purpose of this study is to identify the effects of sedimentation using the SWAT model. To find out changes in land use/cover using the SWAT SUFI-2 analysis. Calibration and Validation are carried out to obtain the accuracy of the model. Model accuracy is measured using Nash Sutcliffe Efficiency values (0.58 and 0.62), and coefficient of determination (R2) (0.69 and 0.62). This condition is influenced by the runoff curve number (CN2.mgt) factor. Sediment prediction averaged 117,027 tons/ha in each sub-watershed. Good management is needed to reduce the rate of sedimentation.