Flood Hazard and Risk Assessment in Chamoli District, Uttarakhand Using Satellite Remote Sensing and GIS Techniques

G.D. Bhatt, Komal Sinha, P.K. Deka, Ajay Kumar
2014 International Journal of Innovative Research in Science Engineering and Technology  
Flood is a major environmental problem in India as it has devastating effects on life and property. The objective of present study is to delineate and identify flood hazard and risk assessment at landscape level using Landsat satellite data from 1974-2013 in Chamoli District, Uttarakhand, India covering total geographical area of 8030 km2. The study area lies between 30-31° N latitude and 79-80° E longitude. The satellite data was ortho-rectified and the study area was extracted using district
more » ... oundary. The vegetation type/land use map was prepared using on-screen visual interpretation technique. The multi-flood time series dataset was used for preparation of Digital Elevation Model. Geographical Information System was used for identification of flood prone areas which were classified with zone-wise. A flood frequency map was developed using the multi-date Landsat satellite imagery. The classified vegetation type/land use map from 1974-2013 was overlaid to find out the frequency of the flood. Flood affected areas were classified into very low, low, medium, high, very high and extremely high based on vulnerability to the potential of flood hazard. The areas were further categorized, based on the vulnerability of flood viz; extremely high (6) very high (5), high (4), medium (3), low (2) and very low (1) respectively. The study assigned the scores to each class for further determination of risk zone in various thematic layers such as slope, aspect and elevation. The incorporation of all thematic layers and flood frequency map was generated to prepare flood hazard and risk map using GIS platform. Flood frequency and flood prone areas were calculated using DEM. The vegetation type/land use map was integrated for creation of flood hazard and risk assessment. Based on this analysis the flood risk zones at different levels and intensity in the Chamoli district were prepared. This flood hazard and risk assessment maps will be useful to management and mitigate losses of lives and property from recurrent flood disasters in Chamoli District. This model can also be applied to comparable areas in Himalayas. KEYWORDS: Flood hazard and risk assessment, Landsat satellite imagery, On-screen visual interpretation technique, Remote sensing and GIS, Vegetation type/land use I. to classify the extent of floods. On-screen visual interpretation techniques for classification systems allowed different tonal variation for different classes that can be used further for similar types of flood mapping. This study demonstrates that information derived from different imagery can be valuable to operational users for flood related planning and emergency response. Natural flood disaster is common and cannot be stop, but we can reduce its impact can be minimized. Remote sensing and GIS is an effective tool for flood hazard, risk mapping, suitability analysis and disaster management. Watershed management practices in the uplands of the catchment are crucial in alleviating future flood disasters in the study area. Land use planning can play a very important role to minimize the adverse effects of flood. It is recommended to adopt an appropriate land use planning in flood prone areas. The ideal form of planning would be to evacuate the flood prone areas but practically it is not possible due to involvement of high costs and social problems. However, it is possible to change the functional characteristics of the flood plain areas. IV.ACKNOWLEDGMENT
doi:10.15680/ijirset.2014.0308039 fatcat:mhiqlnfm6bd2begngbprvriedm