The study aims to estimate the extent of inundation and depth due to a storm surge event by selecting a worst-case cyclone track scenario for Andhra Pradesh, Odisha and West Bengal on the basis of historic data. Storm surge model results for the Orissa cyclone suggest that over 2,150 km2 of land is inundated with an extent of 45 km from the shoreline and 1,100 km2 area submerged with 1-2 m from the ground. Andhra’s model suggests that about 450 km2 of the area is inundated due to which the majority of the area is submerged <1 m from the ground. The West Bengal model is carried out using a synthetic track with a wind speed of 155 knots based on the recent cyclonic storm in Bangladesh. The result shows 5,400 km2 of land submerged by <1 m about 2,700 km2 of the area was submerged by 1-2 m of water. The most affected areas were South 24 Parganas and parts of Bangladesh.

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The present study is to estimate the inundation extent and depth to estimate the extent of damage using geospatial technique caused due to a storm surge. This is achieved by selecting a worst-case cyclone track (Super Cyclonic Storm) scenario for three Indian states, Andhra Pradesh, Odisha and West Bengal based on the historic data. Over 1300 cyclones are observed to have hit the east coast of India in the past 173 years, which is about an average of more than 7 cyclones per year. Geospatial model results for Orissa cyclone (1999) suggests that over 2,150 km2 of land is submerged due to storm surge. The inundation was observed up to an extent of 45 km inland upright to the shoreline with over 1,100 km2 area submerged 1-2m from ground level. This is the worst cyclone (with peak speed 140 knots) of the country known so far to have caused maximum damage. The storm surge model of Andhra cyclone (1996) suggests that about 450 km2 of area inundated due to storm surge where majority of the area is submerged up to1m of water pile. The most affected place is Mummidavaram. Whereas, the results of storm surge model for the state of West Bengal is carried out using a synthetic track passing through West Bengal coast with wind speed of 155 knots (worst case). The model result shows 5,400 km2 of land submerged up to 1m of water and about 2,700 km2 of area submerged under 1-2m of water. The most affected area is South 24 Parganas and parts of Bangladesh. The results of the current study are useful for the coastal cyclone disaster management in order to make decisions on preparedness and disaster risk reduction. These results can also be used for the coastal future development purposes.

The present case study describes the morphometric analysis and its influence on the hydrology of the Suvarnavathi river basin and its sub-watersheds. ALOS DEM is used to extract slope and drainage layers while GIS software is used in the evaluation of linear, areal and relief aspects of morphometric parameters for 13 sub-watersheds of the entire river catchment area. The dendritic drainage pattern of the basin reveals moderate slopes while sub-parallel pattern shows high relief and structural control, especially along the 7th order trunk river of the basin. The circularity ratio, elongation ratio and form factor represent that the elongated study area is in the youth stage of basin development. Sub-watersheds belonging to high relief and slope show high bifurcation ratio and drainage density indicating areas under structural control. Whereas variation in values indicate the difference in topography. Stream frequency of all sub-watersheds shows a positive correlation with drainage density due to the hard rock lithological structures which reveals that the surface area has moderate permeability and groundwater potential is meagre. These studies are useful to mark the groundwater potential zone and artificial recharge area and plan for watershed management.