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

Abstract

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 boundary. 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.

Estimation of flood land use/land cover mapping by regional modelling of flood hazard at sub-basin level case study: Marand basin

“…Since, the use of accurate LULC maps can improve the results of flood risk management (Bhatt et al 2014). In this study, satellite images of Sentinel 2 A with a spatial resolution of 10, 20, and 60 m for different bands were used to generate the LULC Figure 1.…”

Flood risk assessment and mapping in Abidjan district using multi-criteria analysis (AHP) model and geoinformation techniques, (cote d’ivoire)

“…Hence, assessing and predicting floods risk has become essential to offer appropriate solutions for flood and sustainable environmental management. Flood hazard mapping is a vital component for appropriate land use planning in flood areas and mitigation measures (Bhatt et al 2014). It provides accessible charts and maps which can be read easily and therefore, facilitates the identification of risk areas by planners and this enable them to prioritize their mitigation efforts (Bapalu and Sinha, 2005;Forkuo, 2011;Wang et al 2011;Ajin et al 2013).…”

“…Flood management is necessary not only because flood imposes huge damages on the society, but for the optimal exploitation of the land and its proper management. This cannot become technically feasible without effective flood hazard and risk maps (Bhatt et al 2014) More recently in Cote d'Ivoire, populations have experienced increasingly important phenomena of floods, with its effects such as death, damage to property and population exodus. Heavy rainfall is the main natural hazard which causes loss of many lives; destruction of infrastructures, and the displacement of people during the rainy season in Abidjan.…”

Flood Vulnerability Modelling Factors of Nafada Town, Gombe State, Nigeria Using Remote Sensing and GIS Techniques

“…For instance, Asian countries have been at the frontline of the incidence and severity of flooding in the world. It is estimated that the countries experienced 1/3 rd of the 1562 floods that occurred in the world between 1994 and 2004 (Uddin et al, 2013;Bhatt et al, 2014).…”