Comparative Analysis of Spatial Impact of 2012 and 2022 Flood Disaster along Lower Niger Basin in Nigeria

Abstract

In recent times there have been excess flooding due to climate change, which leads to disaster and destruction. Hence the aim of this paper is to investigate spatial impact of the two flood episodes that occurred in 2012 and 2022 along Lower Niger Basin in Nigeria using remote sensing data in GIS environment. Data used include administrative map of Nigeria, time series 30m resolution Landsat imageries captured before and during the peak of the flood episodes, SRTM DEM of 30m resolution and data generated from ground truthing. The pre- flood image was used as reference to determine the extent of flood in the disaster imageries. SRTM data was used for preparation of digital elevation model so as to investigate the influence of topography on spatial spread. This study revealed that 5622.13square kilometers of the study area (7.92%) was covered by flood in 2012 while 7428.771 square kilometers of land (10.47%) was inundated in 2022. This means that additional 1806.641 square kilometers (2.55%) of land surface has been exposed to flood in the study area within a time space of 10years. Upon field verification it was found that this was partly attributed to anthropogenic activities and urban expansion. It was therefore recommended that strict land use planning be enforced within the study area and public enlightenment programs should be initiated.