Accuracy analysis of SRTM usage for upper Citarum River flood modeling

Abstract

Natural channel cross section is generally very irregular and varied, for complex cross-sections and natural cross sections no specific formula presents to express the elements of the geometric cross section of the channel. The study uses HEC-Geo RAS with Arc GIS 10 and HEC-RAS 4.1.0 for modeling and 1D hydrodynamic. The surveyed cross sections modeling is calibrated and validated with observed daily discharge. Then the surveyed data cross sections are replaced by the cross sections extracted from SRTM. Accuracy is suitability between the surveyed data cross sections with data cross sections which extracted from SRTM. Accuracy is expressed by the magnitude of the error. The ratio of simulated discharges between two models by surveyed data cross sections and SRTM data cross sections have index of performance indicator for Nash-Sutcliffe Index (NI) is 0.95 and index of Root Mean Square Error (RMSE) is 0.41. Index of Performance indicator for comparison of simulated discharges between models with Nash-Sutcliffe Index (NI) is 0.95 and index of Root Mean Square Error (RMSE) is 0.41. The results show that cross sections from SRTM can be an alternative to extract data cross sections for Upper Citarum River flood modeling.