STUDY OF THE EFFECT OF SEDIMENT TRANSPORTS ON RIVER’S MORPHOLOGICAL CHANGES AND FLOODS AT SADAR RIVER IN MOJOKERTO REGENCY

• Main Author: Permatasari, Nora
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/79496
• Institution: Institut Teknologi Bandung

Kali Sadar is a collector of several tributaries and is a flood plain that protects a 1.930-hectare of agricultural land areas in Mojokerto Regency, East Java Province. Flooding frequently occurs in the Sadar River's basin at Mojokerto Regency East Java Province every year causes a lot of material losses. Flooding enters the mainland and inundates several vital areas such as agricultural lands, settlements, public places, and economic centers around the left and right of the Kali Sadar. The flood incident was caused by sediment and garbage's narrowing and silting of the Kali Sadar channel. The tributaries leading to the Kali Sadar cannot enter and flow freely into the Kali Sadar. Sediment and erosion can affect changes in river morphology which can cause a reduction in the capacity of the Kali Sadar river because it experiences scouring (degradation) and sedimentation (aggradation) every year. This research aims to analyze the flood spread, changes in river morphology due to sediment transports, and alternatives to practical flood control engineering that can apply. The methodologies used in this study are analyzing the potential for bedload sediment transport using the Engelund Hansen Methode. The hydraulics analysis used the unsteady flow equation and 1D and 2D sediment transport models by including the planned flood discharge for 25th and 50th year return periods and cross-sectional data from upstream to downstream of Kali Sadar. The 1D model analysis resulted in changes in the river's long sections and cross-sections profile and eroded and sedimented river sections. The results obtained in this study of changes in riverbeds experienced an average elevation as high as 1.45 m downstream of the river and degradation of an average of 1.5 m upstream. This problem needs to be handled by dredging the total sediment volume of 2,911 m3 which is done periodically.