STUDY OF LAND COVER CHANGES ON FLOODING IN THE UPPER CITARUM WATERSHED (CASE STUDY OF THE UPPER CITARUM WATERSHED - DAYEUHKOLOT)

• Main Author: Bandjaran Cakti, Adhitya
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/79582
• Institution: Institut Teknologi Bandung

The increased demand for land, coupled with population growth, has altered land cover in various regions, including the Hulu Citarum - Dayeuhkolot watershed. This research seeks to investigate the impact of land cover changes on the escalation of flooding in the Citarum Hulu - Dayeuhkolot watershed The analysis of frequency distribution leads to the conclusion that if rainfall is evenly distributed throughout the Citarum Hulu - Dayeuhkolot watershed with an annual return period of R2, then a Q2 years at the outlet of the watershed. If the rainfall is evenly distributed with an annual return period of R5, then a Q25 years at the outlet. Furthermore, if there is evenly distributed rainfall in the watershed with a return period of R10 years, then a Q1000 year at the outlet. The land cover data used in this study were obtained from the Ministry of Environment and Forestry for the years 1990 and 2022. The research results indicate a significant change, primarily in the type of plantation land cover, which decreased by -8.65%, while residential land cover increased by 38.85% from 1990 to 2022. The water loss analysis in the Citarum Hulu - Dayeuhkolot watershed using the Curve Number method showed a significant increase in several sub-watersheds, such as Citarum Hulu – Majalaya watershed, Cikeruh watershed, and Cidurian watershed. This alteration in CN has resulted in an increase in the estimated flood discharge rates, ranging from 9% to 26%. The estimated flood discharge values were calibrated using the Dayeuhkolot Water Gauge Station, achieving an accuracy range between 97.29% and 99.99% The hydraulic modeling of the river indicates an increase in the flood water level from 1990 to 2022 in Citarum upper river, with the largest increase observed in the Cikeruh watershed (+1.23 meters) and the smallest in the Citarik watershed (+0.28 meters). This change is, of course, also influenced by the Water surface level of the Citarum River