Author(s): Imee Bren Villalba; Warren Gabayeron; Dominic Bautista
Linked Author(s):
Keywords: Flood Map; HEC-HMS; Nays2D Flood; TD Agaton; Pontevedra
Abstract: In 2018, Tropical Storm Bolaven (local name Agaton) brought massive flooding and caused millions of damages in agriculture and fisheries in the Province of Capiz, Philippines, where 12 out of 16 municipalities were affected, including the town of Pontevedra. This study aims to estimate flooding in the town of Pontevedra under Tropical Storm Bolaven 2018 by performing hydrologic and hydraulic modeling using HEC -HMS and Nays2D Flood, respectively. The hydrologic model is developed for the Panay River basin and the hydraulic model is applied to the political area of Pontevedra and neighboring municipalities. Calibration of a gauged Panay River sub-basin using the rainfall data of Tropical Storm Kaitak (local name Urduja) in 2017 and the corresponding discharge data at Dao Bridge is used to determine hydrologic parameters which are then applied to ungauged river sub-basins. The result of the hydrologic modelling for TS Bolaven 2018 rainfall yields a peak discharge of 1,700 m3/s at Panitan Bridge, which serves as the inflow discharge to the hydraulic model of Pontevedra using the Nays2DFlood solver of the iRIC software. Results of the hydraulic model is validated using the flood extent of TD Agaton from situational reports. The generated flood extent and flood map for T S Bolaven in this study is used to provide recommendations of flood mitigating measures in the town of Pontevedra, Capiz, Philippines.
Year: 2020