Author(s): Desmond Ofosu Anim; Amos Tiereyangn Kabo-Bah; Philip Nti Nkrumah; Yiping Li
Linked Author(s):
Keywords: Flood; Northern ghana; MNDWI; Spectral water index; SPOT-5
Abstract: Flood is one of the known natural hazards affecting the environment, human livelihood and economies of nations across the globe. In the northern part of Ghana, regarded as the most flood prone zone, flood hazards have almost become an integral pattern of the annual hydrological cycle. These adversely affect the sustenance and general well-being of millions of people in the region. Moderately and severe flooding cases have been recorded which has seriously affected the people and the economy in this part of the country. However, general reliance of weather data as mostly the case is not enough to monitor areas of flood especially when those data can be sparse, limited, untimely and incomplete. The use of satellite data to augment this to identify the location and susceptibility of an area to flood events has become necessary and timely for a complete, up-to-date and comprehensive coverage of current flood situations. The study thus attempts to investigate the use of multi-spectral SPOT 5 imagery to do a feasibility study of flood hazard analysis and mapping applying the concept of Spectral Water Index (SWI) herein Modified Normalized Difference Water Index (MNDWI). The MNDWI has the ability to delineate water and non-water features in an area. It thereby gives a spatially and temporally continuous short-term indicator of flood conditions and susceptibility. The results shows that the MNDWI coupled with other land monitoring data for the study area could be utilized to successfully map and zone flood risk susceptibility sites. The flood hazard map generated from the results identifies; regions around these areas which are susceptible to the hazard, hazard free regions suitable for development, hazardous regions where if development has taken place requires measures to be taken to minimize vulnerability and regions where hazard investigations are required. This work if conducted over a long period of time can provide sufficient baseline information for the monitoring, evaluation and effective management of flood events in the Northern Ghana. This can help government to save valuable lives lost each year and also monetary expenses which could be used for the building of other important facilities such as road infrastructure, electricity and water services. This case presented here, can easily be duplicated in most parts of Ghana that face similar problems.
Year: 2013