DEVELOPMENT OF DIGITAL ELEVATION MODEL FOR STORM -WATER MODELING FOR COASTAL REGION IN NAGAPATTINAM USING GEOSPATIAL STUDIES

The frequent monsoon fluctuation in the coastal region of Nagapattinam city of Tamil Nadu, which is known to be the rice bowl of southern India, has been imparting increasing insecurity in the yield of the crops, but even the very living conditions of the population, who are mostly dependent on agriculture. Road-expansion (NH-67) of the recent years involving mass-removal of thousands of trees located at the roadside have led to micro-climatic variation over the years. Since most of the agricultural land of the area depends on the irrigation as well as water from canals of Cauvery River, the precipitation (with respect to quantity, duration, and periodicity) has been the lifeline of progress and sustenance of this zone. To track the baseline morphological and lithological regimes of Nagapattinam city of Tamil Nadu (India) precisely, which forms the heart of storm-water modeling, the present study was carried out. The digital elevation modeling (DEM) was developed, using the toposheets and satellite imageries so as to evaluate the basis for hydro-geological modeling.