Abstract:
Floods are one of the common natural disasters occurring in many parts of the world. Floods
result in damage to human life, infrastructure and deterioration of the environment. The
socio economic and ecological impacts of floods are devastating in Africa and other
developing countries, because most of them do not have real time forecasting technology or
resources for post disasters rehabilitation. Flood hazard assessment is based on information
on the intensity and frequency of flood events. Flood in Ethiopia is a major problem; it
destroys life and property every year.
In the Awash River basin, especially in upper Awash (Koka) extensive use of the land for
agriculture and high pressure on the forest for fire wood expose the area for severe flooding
and erosion during high rainfall. So Flooding has becomes a more common threat for the
people living in Awash River basin. Accordingly, the objective of this thesis is preparation of
flood hazard map. Since, rainfall is the major force driver of floods, the temporal and spatial
distribution of precipitation is the key parameter for flood hazard mapping. Using remote
sensing and GIS technology is proved to be the most advanced to identify the flood hazard
prone areas of a watershed, region, or country in small and large scale. ‘Koka’ area which
is a part of Awash River basin is experiencing severe floods for many years due to
deforestation and erratic rainfall pattern. In the present study an attempt is made to identify
the flood prone area by integrating different themes which has direct and indirect influence
in occurrence of floods. Topography, soil, drainage, land use/cover and rainfall data are
used to model the flood hazard of ‘Koka’ area within the Awash River basin using Satellite
Remote Sensing data and GIS technology. GIS technology is one of the new technologies
used to collect, store, analyze and display large amount of spatially distributed information.
Using the above data a GIS based hazard map is prepared,
this can be used for decision making process in the emergency response in flood disaster.