ANALYSIS OF EROSION RATE, SEDIMENTATION, AND AGE OF RESERVOIR (CASE STUDY OF WEST JAVA SAGULING RESERVOIR)

• Main Author: Annisa Royani, Rani
• Format: Theses
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/68525
• Institution: Institut Teknologi Bandung

The increase in the erosion rate in the Upper Citarum watershed has resulted in an increase in the volume of sediment in the Saguling Reservoir so that silting occurs and the capacity of the reservoir decreases. Therefore, an analysis of the erosion and sedimentation rate on the Scale of the Citarum Hulu watershed was carried out as an effort to mitigate and inform to estimate the length of life of the Saguling Reservoir. Erosion rates were analyzed based on the Universal Soil Loss Equation (USLE) model with the integration of geographic information systems (GIS). The amount of sediment in the Upper Citarum watershed exported to the Upper Citarum watershed outlet was analyzed based on the sediment delivery ratio. Analysis of the life of the reservoir uses the equation of the line of inclination between the time of operation and the volume of sediment entering the Reservoir. The erosion rate of the Citarum Hulu watershed in 2012 was 291,893.04 tons/ha/year with 31.05% light erosion class, in 2015 it was 166,302.47 tons/ha/year with 35.30% heavy erosion class, in 2016 it was 85,440.05 tons/ha/year with 29.50% very heavy erosion class, in 2017 it was 327,713.85 tons/ha/year with 28.70% light erosion class and 27.90% moderate erosion class, and in 2018 it was 328,998.84 tons/ha/year with 26.70% of the heavy and light erosion class. The SDR value indicates erosion carried on the surface of the land to the Citarum Hulu watershed outlet by 92%. The mass of sediment exported out of the Upper Citarum watershed in 2012 was 3,649,852.55 m3 / year, 2015 was 2,079,458.59 m3 / year, 2016 5,407,447.86 m3 / year and in 2018 it was 4,113,826.23 m3 / year. The equation of the trend line on the volume of sediments is y = 31,276.41x - 58,415,038.77, so that the dead storage capacity will be full because the volume of sediment accumulates, which reaches 167,472,464.23 m3 in 2024 with a reservoir function life of 39 years. The ranking of sediment management strategies in the Saguling Reservoir is the first rank of conserving soil and water in the Citarum Hulu watershed with a weight of 55.4%%, the second is an alternative to building erosion rate suppression infrastructure in the Upper DTA of the Saguling Reservoir in the form of sediment storage with a weight of 31.6%, and the third is an alternative to sediment dredging with a weight of 13.0%.