Application of a digital elevation model for flood modeling for the Pagsangaan River in Leyte
This PhilGEOS 2012 paper provides an example of computerized flood modeling in Pagsangaan River Basin, Leyte, Philippines. It asserts that flood related scientific and community-based data are rarely systematically collected and analysed in the Philippines. Over the last decades the Pagsangaan River Basin, Leyte, has experienced several flood events. However, documentation describing flood characteristics such as extent, duration or height of these floods are close to non-existing.
To address this issue, computerized flood modeling was used to reproduce past events where there was data available for at least partial calibration and validation. The model was also used to provide scenario-based predictions based on A1B climate change assumptions for the area.
The resulting flood maps are now used by the operations centre of a local flood early warning system for warnings and evacuation alerts. Furthermore these maps can serve as a basis to identify flood hazard areas for spatial land use planning purposes.