Flood Hazard and Risk Assessment of Deoha River Basin, Central Ganga Plain, India: An GIS approach

Abstract

Flood is a natural disaster worldwide and it occurs primarily in any plain area due to geological and environmental phenomena like geomorphological process, monsoonal effect, lithology etc. Such plains are also severely affected often by catastrophic flooding and are currently recommended to be the worst flood-affected region in the world. This research aims to classify the flood-prone areas of the Deoha River basin based on the weighted overlay assessment method using Arc-GIS-10 and ERDAS-14. by multi-criteria assessment, in which weights are assigned for each class based on multi parameters with restricted variables to prepare a map of the flood-prone areas. The average annual rainfall (80-200 cm), stream frequency (0.0001 to 0.3563 stream number/km2), slope (0-50-350), drainage density (0-545.94 magnitude/m2), channel gradient (0.27-22.52 m/km), landuse/landcover (cropland>water bodies>built-up>scrubland >forest.) and soil type (loam>sand>clay) prefer the susceptibility of flood-prone in the basin area. The weighting maps are generated by providing ranks and weights to these thematic maps. As a result, the flood hazard risk zonation map would show the total area vulnerable to hazards as very medium, low, moderate, high and very high-risk regions. By creating a risk zonation map, we will recommend measures to reduce the danger of these hazards in Deoha basin.