Geomatic Approach to Assess the Flash Floods using Land Use Land Cover Maps–A case study of Kodagu district

Abstract

World has witnessed several disaster management in the recent times owing to the impacts of climate change, amongst them flood is the most frequent and expensive natural disaster Flash floods occur almost every year in one or the other part of the country resulting tremendous loss of life, large scale damage to property and untold misery to millions of peoples. Unchecked concretization and acute loss of wetland and vegetation over the years are the prominent reasons causing frequent floods. There could be several reason for such a flash flood but the one being more importantly dealt in this work is due to anthropogenic impacts of environment. Land Use (LU) Land Cover (LC) greatly reflects on the interaction between human and its environment. The work discussed here takes up with analysis of the flash flood occurred in the regions of Kodagu district, located in the south-western part of Karnataka, India (11̊ 52’ N-11̊ 56’ N and 76̊ 12’E -76̊ 22’E). QGIS a Geographic Information System application tool and BHUVAN an ISRO operated geospatial data have been robust Geomatic tools for mapping the flood effected areas. The work aims in the analysis of the LU/LC maps to predict the reasons for flash floods in the study area. Upon examination it is found that, Virajpet has relatively faster rate of forest encroachment than the other two taluks of the study area. It was observed that these forest encroachments had a variation of 0.56% , 0.89%, 0.94% and 0.98% in a ascending year of consideration1990, 2000, 2010 and 2016). Faster rate of encroachments was observed during 2010 and 2016.Thus, with the concern of sustainable development study suggests Non-structural measures to mitigate the natural disasters such as : i) Afforestation to minimize surface runoff by vegetation cover ii) Flood plain zoning and iii) Flood forecasting and warning will greatly help to mitigate the disasters.