Floodwater detection in urban areas using Sentinel-1 and WorldDEM data

Remote sensing using synthetic aperture radar (SAR) is an important tool for emergency flood incident management. At present, operational services are mainly aimed at mapping in rural areas, as urban areas hampered by the complicated backscattering mechanisms occurring there. A method detecting flooding high resolution that may contain dense housing presented. This largely uses remotely sensed data sets readily available on a global basis, including open-access Sentinel-1 SAR data, WorldDEM digital surface model (DSM), and World Settlement Footprint to identify areas. The change detection technique locally estimates levels It searches increased backscatter post-flood image due double scattering between water (rather than unflooded ground) adjacent buildings, reduced away from slopes. Areas of detected comparing interpolated level DSM. was tested two events occurred UK during storms Winter 2019–2020. High accuracies were achieved event moderate density housing. accuracy housing, when street widths became comparable DSM resolution, though it would still be useful has potential use near real-time basis.