Analysis of Sediment Transport on the Upstream Code River, Indonesia

摘要

Purpose: The Code River is one of the pathways from debris flows of Mount Merapi that crosses the centre of Yogyakarta City, Indonesia. Along the Code River, there are densely populated areas, mainly when the river flows through the centre of Yogyakarta City. Mount Merapi is one of the most active volcanos in Indonesia, also in the world. Based on the data, the volcano usually erupts in 3-year periods for a small scale and nine years for a large scale. Its eruptions produce a considerable material. The eruption material from Mount Merapi carried by the debris flows affected the sedimentation process in rivers that originated in the volcano, particularly the Code River. This research was conducted to find out the amount of sediment transport and its impact on the upstream area of the Code River. Methodology: Methods used in the determination of sediment transport at Code River are Frijlink, Meyer Petter Muller, and Einstein method. Results: Based on the results, it shows that according to the Frijlink method, the sediment transport occurred is 19.79 – 85.43 m~(3)/day and the sediment transport of MPM method is 15.06 - 77.23 m~(3)/day, whereas the sediment transport of Einstein's method is 8.89 – 70.36 m~(3)/day. The results also showed that the calculation of sediment transport using the three methods, a phenomenon of erosion took place at a location between observation points 1 and 2, and a phenomenon of sedimentation occurred at a location between observation points 2 and 3.