1. G.O. Enaruvbe & G.U. Yesuf
Regional Centre for Training in Aerospace Surveys
(RECTAS) Obafemi Awolowo University, Ile-Ife,
Nigeria
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2. Introduction
Flood disasters are among the most destructive natural
disaster in history.
Flooding has become more prevalent over the past
decades in Nigeria.
The recent incidence of flood disaster in the country
has been attributed to increased rainfall and
infrastructure failure.
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3. Introduction Contd
Coastal farming communities are the most adversely
affected as their farms and fishing implements are
inundated or washed away by the floodwater
An important aspect of flood disaster management is
the provision of timely information, necessary for
mitigation of the impact of the disaster.
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4. Introduction Contd
Maps play a vital role in the presentation and
assessment of the local flood situation. They provide
information for flood management strategies
Research indicates that the integration of Remote
Sensing and Geographic Information Systems (GIS)
provide valuable spatial information in the event of a
natural disaster
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5. The Study Area
Delta State lies approximately between longitudes
5°00 and 6°45'E and latitudes 5°00 and 6°30'N
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6. Figure 1: Study Area
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7. MATERIALS AND METHODS
To determine the vulnerability of the entire state to
flooding, Digital Elevation Model (DEM) covering the
entire state generated from ASTER image.
The scenes covering Delta State were mosaicked
within ArcGIs software environment, and transformed
to the projected coordinate system -WGS 1984 UTM
Zone 32N
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8. MATERIALS AND METHODS
The DEM was classified into three vulnerability
classes, using the variation in elevation values
Visual image interpretation and on-screen digitising
was used in extracting the land use land cover of the
state from medium resolution images derived from
Google Earth
Their non-spatial characteristics and spatial extent
were also determined
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9. MATERIALS AND METHODS
The Multi-Resolution Land Characterization regional
and land cover classification (MRLC) system
(Vogelmann et al. 1998) is adopted in categorizing the
land use types in the entire state
On the basis of the MRLC classification systems, the
state is classified into four major land use classes
(Waterbody, Settlement, Bare surface and Vegetated
surface).
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10. MATERIALS AND METHODS
The risk map of the study area was generated from the
ASTER image
The categories are highly vulnerable, vulnerable and
non-vulnerable areas. A field survey of areas affected
by the flood was conducted in order to assess the
extend of the flood
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11. MATERIALS AND METHODS
It was observed that the flooding of the River Niger
affected communities as far as 5 kilometer from the
River banks
A buffer of 5km was therefore created for River Niger
and its major tributaries and 2km for minor
distributaries
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12. Figure 2: Digital Elevation Model of Delta State 12

13. Figure 3: Flood Map of Delta State
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14. Figure 4: Flooded Farmland
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15. Figure 5: Flooded Settlements
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16. An area of over 7,950km2 or over 49% of the coastal
and riverine communities of the State was inundated.
This affected about 39 communities and over 137.1
hectares of farmland across the State
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17. Conclusion and Recommendation
Remote Sensing and Geographic Information Systems
techniques were adopted in examining the extent and
impact of the recent flood disaster on agriculture and
human settlement in the study area
The use of ASTER images for the generation of DEM
seems effective in mapping flood prone areas in the
State
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18. Conclusion and Recommendation
The results of the study indicate that a large part of
coastal and riverine communities in the State are
affected by the flood, inundating many farmlands and
washing away fishing equipment
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19. Conclusion and Recommendation
This implies that climate change has far-reaching
implications on agriculture, food security and social
stability in the Niger Delta as food prices are likely to
skyrocket as a result of low agricultural productivity
and food scarcity
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20. Conclusion and Recommendation
This situation is likely to result in increased threat of
hunger and malnutrition in the area
Since flooding is aggravated by obstruction to natural
water channels
it is important that urban and regional development
plans be rigorously pursued and implemented to avoid
a situation where buildings and other structures are
constructed on natural drainages
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21. Thank You!!
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