The areas at risk were obtained by overlaying the flood hazard
index map with the zone boundaries layer. Determination
of the areas at risk was needed for flood warning and floodplain
development control. About 25% population residing
in 17 zones is vulnerable to low, 50% population belonging
to 23 zones vulnerable to moderate, 9% population belonging
to 17 zones vulnerable to high and about 16% population
belonging to 11 zones is vulnerable to very high flood hazard
risk in the study area. The high and moderate risk areas are
mostly in the relatively larger basin watersheds with high curve
number, surface slope and drainage density