Spatial Variability of Flood Hazard Risks in the Balasore Coastal Block, Odisha, India

Abstract

This paper pays attention on measuring and assessing the coastal flood hazard risk through quantification of flood intensity and impacts across the different Gram Panchayats (GPs) in Balasore block, Odisha, India. With respect to the June, 2008 flood event, enormity of flooding has been calculated for each GP using normalised values of measurable parameters relating flood characteristics. Thus, a Flood Magnitude Rank (FMR) has been assigned to each of the GPs according to degree of flooding severity. Similarly, Flood Impact Rank (FIR) for each GP has been derived from damage database. The product of FMR and FIR gives Flood Severity Score (FSS) of a GP which when multiplied by probability of flood event occurrence yields Flood Hazard Score (FHS) for the GP. The analysis helps dividing the study area into five flood risk zones viz. a) Very Low (FHS Below 2.0653); b) Low (FHS 2.0653 – 3.2755); c) Moderate (FHS 3.2755 – 4.4857); d) High (FHS 4.4857 – 5.6959) and e) Very high (FHS Above 5.6959), respectively. Joydebkasba, Parikhi, Bahabalpur, Sartha, Srikona falls in very high flood hazard risk class while, Patrapada, Sindhia, Rasalpur 2 tend to have very low risk from flood hazards. The rest 19 GPs along with the Balasore town of the area under study come under different risk classes in between the above two extreme classes according to their flood hazard scores.