Extreme Event-based Rainfall-runoff Simulation Utilizing GIS Techniques in Irawan Watershed, Palawan, Philippines

River flow assessments and ecologically sustainable water management plans are now possible due to the advancement of sophisticated computer models. The US Army Corps Engineers developed HEC-HMS model, which can be used for various hydrological simulations. Rainfall-runoff modeling aids in estimating peak flows, is critical resource planning. On December 18, 2017, a heavy rainfall event ungauged Irawan basin Puerto Princesa City, Palawan, Philippines, was simulated determine amount water. current research aims construct rainfall-runoff simulation model. A specific hyetograph make hydrographs basin. This study utilizes ArcGIS QGIS, perform geospatial analysis provide model's hydrologic inputs. parameters were determined using soil type, land use, cover maps. Incorporating SCS loss, Clark unit hydrograph, Muskingum routing, employed simulation. Rainfall data corresponding recorded streamflow calibrate validate parameters. Several performance metrics, including Nash-Sutcliffe efficiency (NSE) Percentage Bias (PBIAS), utilized evaluate overall effectiveness system. An effective decision-making warning system implemented Doi: 10.28991/CEJ-2023-09-01-017 Full Text: PDF