Abstract:
The study evaluated the flood prone area of Igbokoda town in Ondo State and
developed a flood risk map to facilitate proper planning to mitigate measures against future event of flooding. Scientific technique of GIS was used to identify flood risk areas within the study area. The Landsat 5 (TM), Landsat 7 (ETM+) and Landsat 8 (LC) images for 1986, 1999 and 2013 coupled with STRM 90 m DEM data of the area were used to produce three categorizing risk zones. Hydrological and vegetation cover analysis were conducted using the satellite imageries obtained from United States Geological Surveys Archive online over the study area for three different epochs 1986, 1999 and 2013. The results show that there was a sharp decrease in area of vegetation cover from 1986 (19,630.458 ha) to (1999) (16,527.36 ha) and in (2013) (12246.80 ha) which according to literatures might have pose threat on the environment around this area by increasing surface runoff of water and also possibility of flooding event in the low lying parts of the town whenever there is torrential rainfall. The hydrological analysis revealed that the major part of the residential area falls within the largest basin delineated over the study area. Igbokoda is a low plain area associated with low elevation and high slope angle which contributes to the susceptibility of Igbokoda township to flooding event. This study recommends the implementation of flood control policies and flood early warning systems by the government and placing high priority on the environmental related issues.
