Flood Estimation with Application of Surface Water and Ocean Topography (SWOT) satellite data in Gandaki River Basin, Nepal
Sherchan B (a) and Bhandari K P (b)

(a) and (b) Department of Geomatics Engineering, Institute of Engineering, Tribhuvan University, Nepal

Abstract

Quantifying flood magnitudes is an important aspect of river basin management, particularly related to harnessing of the water resources (for various uses like drinking water, irrigation, hydropower, inland navigation, etc.), management of water induced disaster, and for planning and design of infrastructures that are supposed to be built across the river and on either side the river. However, there is a huge gap in field data in Nepal, resulting in poor level of planning, management and implementation of water related facilities, causing significant loss of lives and properties. Remote sensing data such as Ka-band radar interferometer (KaRIn) under SWOT mission provides direct measurements of water surface elevation (WSE), width and water surface slope of a river which were used to derive the discharge data for the year 2023. Discharge data derived in such a way have been validated with the directly observed data acquired from the Department of Hydrology and Meteorology (DHM). The results correlate with the observed data implying that the satellite data acquired from SWOT mission are are very useful to fulfill the spatial and temporal data gap in the areas such as Gandaki Basin. The research is ongoing and provided the recent data are available the research will continue for the year 2024 and 2025.

Keywords: SWOT, flood, interferometer, discharge

Topic: Topic B: Applications of Remote Sensing