Abstract:
Under climate and land use changes, water cycle is expected
to be intensified. This will likely result in frequent hydrometeorological extremes events such as droughts and floods,
and affect the water balance components. A distributed model
(WaSiM) was calibrated and validated to evaluate water
resources and flood hazard in the Zou catchment, Benin,
for the period 1991–2009. The model was calibrated and
validated at a threshold of 120 m3
/s and its performance
in simulating lower discharge was evaluated. The results
show that the model was able to satisfactory simulate
streamflow using different thresholds with the Kling and
Gupta efficiency (KGE) between 0.5 and 0.85. The model
performance decreases with increasing discharge threshold. The overall water balance predicted by the model is
consistent with the hydroclimatic condition of the basin.
The runoff coefficient varies between 15% and 18% (11%
and 14% respectively) of the total annual rainfall during
the calibration (validation) period. By considering the
discharge above the threshold of 120 m3
/s the model performances were acceptable with regards to the uncertainties in discharge measurement mainly in peak discharge.
Hence, the model is able to reproduce satisfactorily the
hydrological processes in the study area and could be used
for impact assessment.
