Flood control management recommendation of Citarum Hilir sub-watersheds using remote sensing and geographic information system approach

Floods that occurred in the Citarum watershed are caused by land degradation and environmental damage following the population and economic pressure on its surrounding. To overcome this problem, proper planning and uninterrupted observation on the physical characteristics of the watershed are needed. This study aims to: 1) identify the physical characteristics of the Citarum Hilir Sub-Watershed that affect the flow coefficient; 2) calculate the flow coefficient by considering the physical characteristics of the sub-watershed; 3) provide management recommendations of the Citarum Hilir Sub-Watershed for flood control. The method to identify the flood characteristics is by calculating the coefficient of river flow using Cook method which incorporates parameters of slope, soil infiltration, land use, and drainage density, deducted from DEM SRTM and Landsat-8. Using Multiparametric GIS Analysis, the result shows that the physical characteristic of land use contributed the most, which is 34.55 to the flow coefficient assessment. The slope parameter has an influence of 25.44, soil infiltration is 11.42, and drainage density is 28.60. The total flow coefficient value is 52.32, so it is classified as high criteria. Therefore, this area has high flood potential that are prioritized for handling flood control. This area covers a land unit with high to extreme flow coefficient values, which is 73.96 of the total area. Several efforts can be made to follow up the flood control on these priority areas, such as land use management, forest and land rehabilitation, soil and water conservation, and integrated watershed management. Land use planning must refer to this analysis to determine the suitability of land use for water and forest conservation to remediate those high to extreme flow coefficient values. The evaluation on Regional Planning Map of West Java Province in 2009-2029, is needed as a recommendation to control the flood and enhance the Citarum Hilir management. © 2021 SPIE.