www.ijcrt.org © 2018 IJCRT | Volume 6, Issue 2 May 2018 | ISSN: 2320-2882
IJCRT1135347 International Journal of Creative Research Thoughts (IJCRT) www.ijcrt.org 311
Assessment of GIS and Remote Sensing-Based
Flood Vulnerability of Shilabati River Basin Using
AHP Method
Ujjwal Bhandari
1
and Mousumi Roy
2
*
Syamaprasad College, 92, Shyama Prasad Mukherjee Rd, Jatin Das Park, Patuapara, Bhowanipore, Kolkata,
West Bengal 700025, India
1
Vivekananda College for Women, Diamond Harbour Rd, Jadu Colony, Barisha, Kolkata, West Bengal
700008, India
2
Abstract:
Floods in the Shilabati River basin (3,019 km
2
) are due to both climatological reasons and a combination of other
factors related to the catchment. The existing flood risk forecasting system by the Indian Meteorological Department is
devoid of a sound flood forecasting system though the downstream catchment is frequently affected by flood every
alternative year. Therefore, in this study an attempt has been made to develop a workable forecasting system,
considering remotely sensed data for analysis. Both the multi-criteria-based weightage method and the based approach
are considered for finding the flood risk zones of the basin. Most of the agricultural watersheds in India are ungauged,
having no records of the rainfall-runoff processes. This has led to the development of techniques for estimating surface
runoff from ungauged basins. From the several methods for runoff estimation of ungauged watersheds, the curve
number method (SCS-CN) is used here as a distributed model whose method along with its derivatives has been widely
applied to ungauged watershed systems and has proved to be a rapid and accurate estimator of surface runoff. This
method was originally developed by the US Department of Agriculture, Soil Conservation Service and documented in
detail in the National Engineering Handbook, Hydrology (NEH-SCS). Landsat satellite images were used to obtain
land cover information through the ERDAS Imagine 9.2 platform. The thematic layers like soil map, elevation map,
rainfall map, and land cover map were created in the TNT mips platform. Curve numbers are assigned for different
land cover and soil types. In the present study, the runoff varies from 3.91 mm to 64.83 mm of the study area. From the
above-said method, we create an index-based vulnerability analysis that predicts the risk zones of the study area.
Finally, five categories of flood risk were established (very low risk to very high flood risk zones; 0.009 to 0.088).
However, it can give the flood risk probability in the basin very precise and cost-effective.
Keywords: Flood vulnerability, Shilabati river basin, Geospatial technique, AHP, Flood risk index
1.1 Introduction
Overflow of tidal or inland water by rapid accumulation of runoff in normally dry regions as partially or
completely is a general temporary condition of Flooding (Jeb and Aggarwal, 2008). Floods are considered
one of the most vulnerable natural hazards and are generally turned into disasters (Alcantara Ayala, 2002).
Precipitation mainly occurs in the monsoon months (Viz. June to September). Floods cannot be controlled