Using Geographical Information System to Estimate Vulnerable Urban Settlementsfor Flood Hazard and Risk Assessment in City

The rate of urbanization in recent years is astounding. About 50 years ago, only three out of ten people in
the world lived in cities. Most of these were in the development countries. Now about 50% of the world
population lives in cities, and by 2020 it is expected that six out of ten people will live in cities. Most of the
new growth is in the less developed and least developed countries. For the first time in world history, more
people now live in cities than in villages (UN Population Division). This fact indicates that population growth
tends to occur in urban areas. The growth of highly concentrated urban areas has crucial implication for the
vulnerability of the cities and their residents. Disaster do not of course specifically target cities, but they will
have much greater impact on human life and property when they will have much rather than the fairly
disperse and less populated rural areas.
This paper seeks to demonstrate a method to more accurately estimated urban settlements vulnerable to
hazard by using suitable indicators for identifying vulnerability to flooding, especially in densely developed
cities, and to characterize at-risk populations based on measures social, physical, and environment
vulnerability. We discuss two methods that employ Geographical Information science to access and quantify
risk and vulnerability and Flood hazard analysis method to understand the likeliflood of flood occurences.
The two methods will show the vulnerability of the city due to flood hazards This methods can serve as a model to helps other municipalities to estimate vulnerability to hazards, tailored to the specific conditions and characteristics of their locales. While this paper focused on the flood threat,
the models can estimate vulnerability and exposure to other types of hazards such as earthquake, extreme weather events, and technological disasters.