Katsina-Ala drainage basin
event of the dam failure,
es within the Earth crust,
down the Katsina-Ala and
' distinctly marked fracture
rection and may serve as
r transport. Fourteen Local
Nigeria and Cameroun are
ollapse of the lake because
nd contiguity and tangency
he floodplains (Figure 2).
Many studies have shown that the fault lines are still very active.
(Mesmin et al, 2000) and this risk is highly linked to the
increasing number of people in this region. The return of the
local population, who for the past 20 years had been living in
Bua Bua and other resettled localities, has increased the fear of a
more deadly disaster (Tazief, 1989, Mesmin et al 2010). Some of
the consequences include the depletion of underground water,
deforestation and extreme poverty and death, particularly in the
event of another gas explosion and flooding. The degasification
process which is still in progress points to this fact. The gas
emitted during the 1986 explosion mostly flowed across the fault
lines; the population which settled along these lines were the
most affected. The tectonic activities and the frequency of
landslides, especially during the rainy season, constitutes another
risk to the population To this effect, the region needs to be
constantly surveyed and monitored.(Mesmin et al 2000).
Research findings from fieldwork revealed that the survivors of
the previous disasters are the poor people who are socially
vulnerable to the impacts of the past gas explosion tragedy.
Twenty two years after the Lake Nyos Disaster, the survivors
have not regained their livelihoods; many of them still have very
low resilience and limited coping strategies. This include failed
government promises to provide financial and material assistance
to disaster victims, provide basic social facilities and ameliorate
their housing and living conditions and also the inability to solve
other social problems within resettlement zone despite persistent
complains (Bang, 2008). While huge sums of money are pumped
into the degassing project, the disaster survivors languish in
abject poverty in the resettlement camps with a catalogue of
numerous social problems that remain unresolved. This
unfortunate situation made many of them to go back to their
former means of livelihood and settlements such as the sale of
cattle, farming and hunting, thus increasing their vulnerability to
the Lake Nyos-triggered disaster.
The results from field work and hydrological modelling in a GIS
provide viable and reliable information on the dam’s fragility
and the vulnerability of the region to floods and erosion.
5.0 CONCLUSIONS
The frequency of occurrence of natural and man-induced hazards
and disasters in West Africa sub-region and globally has
necessitated the need for constant studies using multi-
disciplinary approaches to provide adequate information that will
help mitigate the impacts of these hazards and disasters. Poor
disaster management policies and practices are partly responsible
for the poverty and poor living conditions of the survivors, and
this appears to be a key determinant for the social vulnerability
of the local population to the effects of the past disaster and
subsequent hazards. The management of the disaster associated
with lake Nyos gas explosion in 1986 shows a typical example of
unfulfilled government’s promises to disaster survivors and a
failed policy towards disaster risk reduction. The foregoing
therefore informed the need for disaster mitigation planners to
alert the governments and other relevant NGOs of their
responsibilities to the disaster community ahead of any disaster
occurrence (Liebow and Wolfe, 1993).
Lake Nyos holds an enormous volume of CO2 which erupted
and kill over 3000 people and livestock at Oku volcanic field in
1986. Integration of satellite data and hydrological models in a
GIS combined with social and economic development surveys of
the settlement/population around the lake and Katsina-Ala
11
drainage basin will go a long way in improving the management
of future disaster in the region. Early review of available flood
hazard information and the integration of complementary flood
hazard assessments data will allow planners to foresee and
evaluate potential problems related to river hydraulics and
floodplain dynamics. The nature of social vulnerability and risk
perception of community to hazards is also essential and must be
incorporated into disaster risk management policy and practice
by the authorities. Then, mitigation measures can be identified to
avoid or minimize these hazards; this can be incorporated into
the formulation of specific sectoral investment projects.
5.1 References
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disaster, Cameroon, 1986: the medical effects of large scale
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Bang H.N, (2008) Social vulnerability and risk perception to
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disaster: what future prospect for the displaced disaster victims?
Paper presented at the 2008 summer academy for social
vulnerability at the united nations university-institute for
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Blaikie, P.; Cannon, T.; Davis, L; Wisner, B. (1994): At Risk:
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Kling, G.; Clark, M.; Compton, R.; Devine, D.; Evans, W.;
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Liebow, E.; Wolfe A. (1993) Communities at risk:
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