TITLE:
Spatial Assessment of Flood Vulnerability in Aba Urban Using Geographic Information System Technology and Rainfall Information
AUTHORS:
Chidi Enyinnaya Ogbonna, Felix Ike, Virginia Ugoyibo Okwu-Delunzu
KEYWORDS:
Flood Vulnerability, Rainfall Trend, GIS, Topography, Poor Drainage
JOURNAL NAME:
International Journal of Geosciences,
Vol.6 No.3,
March
11,
2015
ABSTRACT: This study investigated
the relationship between topographic information and trends in rainfall in Aba
urban, South Eastern Nigeria. GIS data were applied to generate topographical
information onrunoff
characteristics, the slope, the contour, the aspect and the digital elevation
model. The Mann-Kendall Trend was applied to the rainfall data to show if a
monotonic increase, decrease or stability trend exist for the rainfall data of
Aba metropolis for the period 2000-2010. Results showed that virtually all
parts of Aba were liable to floods expect Ogbor hill axis. The flood
vulnerability map indicated that 71.65% of the study area was vulnerable to
flood. Rainfall trend showed a decrease in six out of the ten year period.
Since within this period, flood intensity had generally remained the same, we
concluded that topography, poor drainage infrastructure and non-compliance with
building, planning and environmental regulations rather than rainfall trend
were the key cause of flood problem in the study area.