Spatial Distribution Pattern and Terrain Analysis of Urban Flash Floods and Inundated Areas in Maiduguri Metropolis, Borno State, Northeast, Nigeria

Abstract

Maiduguri metropolis Nigeria, lies on a relatively flat terrain of about 350 meters above sea level and is part of the undulating Borno Plain that slopes towards the Lake Chad. The rapid physical expansion of the metropolis and the annual recurrent flash flooding and inundation problems within the city continues to impact devastating socioeconomic effects on the livelihood of residents sometimes leading to loss of lives and property. It is important therefore to understand the spatial pattern of floods and terrain characteristics in Maiduguri for planning purposes. The paper examined the spatial pattern of urban flash floods and inundations, and the terrain characteristics in Maiduguri metropolis. Digital Terrain Model (DTM) generated from the Shuttle Raddar Topography Mission was used to provide the basis for the terrain analysis to generate hydrological parameters such as elevation, flow accumulation and direction, drainage network and slope angle as well as classified elevation images and terrain wetness index to map out potential flood risk areas. The DTM identified potential areas liable to flash flood and inundation. The 3D Digital Terrain Model (DTM) of the area showed where potential floods or traps were located in the metropolis. The findings further revealed that Maiduguri was generally characterized by low lying locations with slope angles of less than 5 degrees covering an area of 144.4 km 2 out of 148 km 2 making it extremely difficult to drain. The processed flow accumulation of the study area showed a high flow accumulation pixel value of 19,972 that drained into outlet, suggesting that a large proportion of the study area was getting flooded during a rainstorm. Even though the calculated drainage density of 0.73 for the study area indicated a very good drainage system, this was also undermined by the flat terrain and urbanization. The study recommends for improved land use planning; raising awareness of the residents, provision of more drainages and continued vulnerability mapping improved the functionality of bodies responsible for flood management among others for sustainable flood management in the study area.

Effects of Aircraft Noise on Residential Properties Rental Value Around Maiduguri International Airport, Borno State, Nigeria

“…Maiduguri, a town in Northeastern Nigeria, is located between latitudes 11˚04`N and 11˚44'N; and longitudes 13˚04'E and 13˚44'E. It covers a complete land space of 543 km2, which makes it the biggest city in the Northeast Nigeria (Jimme, Bashir and Adebayo, 2016).…”

“…The area is in the huge open landmass that is flat or slightly undulating, evolved on younger sedimentary rocks of the Chad formation. This exceptionally flat terrain is sloping closer to the Lake Chad and has an elevation ranging from three hundred metres and six hundred metres above sea level (Jimme, Bashir and Adebayo, 2016;Emoh, Yusoff, Zahari and Ismail, 2015). Maiduguri lies on, and at the lowest parts of the Bama Ridge which runs in a Northwest/Southeast route from the Nigeria-Niger boundary to the Cameroun Mountains along the Southeast.…”

Flood Vulnerability Mapping of River Ngadda Using Geospatial and Remote Sensing Techniques Maiduguri Metropolis, Borno State

“…Some other researchers have considered assessment of ood within Maiduguri and its environs using different methodology. Jimme, Bashir and Adebayo (2016) studied the Spatial Distribution Pattern and Terrain Analysis of Urban Flash Floods and Inundated Areas in Maiduguri Metropolis. His study used data generated from Shuttle Raddar Topography Mission and ndings presented low lying locations within the study area, identifying potential areas liable to ash ood with a conclusion on recommendation on a continued vulnerability mapping improved which this research will provide.…”

Vulnerability assessment for flash floods using GIS spatial modeling and remotely sensed data in El-Arish City, North Sinai, Egypt

“…ArcGIS Spatial Analyst tools are used to derive elevation and slope of the study area. Jimme et al (2016) and Niyongabire et al (2016a, b, c) extracted elevation from DEM to study floods. Elevation is the height of a point above (or below) sea level.…”