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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. [ABSTRACT FROM AUTHOR]

One of fundamental problem in waste management is to identify suitable locations for refuse dump. This is because it requires integration of numerous economic and environmental factors. Therefore, the objective of this paper was to use Geographic Information System (GIS) for the selection of sustainable waste disposal site in Owerri West, Imo State, Nigeria. Data used include shuttle radar topographic mission (SRTM DEM) data of 3 arc seconds, LANDSAT satellite data of 30m resolution, geological data, google earth satellite imagery, administrative map of the study area and ground control point (GCP) collected by ground point survey (GPS). These datasets were populated in ArcGIS 10.5 window and harmonized in a common coordinate system. Six factors which include nearness to river and road, settlement, land use, slope and elevation were considered as waste dump siting constrains. These factors were weighted, reclassified and Analytic Hierarchy Process (AHP) and GIS over lay analysis were combined in selecting optimal and sustainable waste dumping locations. The results of the study are categorized into highly suitable, suitable, moderately suitable and unsuitable. Field observations also confirmed suitability of the selected sites. The highly suitable locations are those that possess the optimal quality and characteristics for sustainable waste disposal while the suitable sites can be kept as back up for future use. [ABSTRACT FROM AUTHOR]