Establishment of a Stochastic Model for Sustainable Economic Flood Management in Yewa Sub-Basin, Southwest Nigeria
Abstract: Of all natural
disasters, floods have been considered to have the greatest potential damage.
The magnitude of economic damages and number of people affected by flooding
have recently increased globally due to climate change. This study was based on
the establishment of a stochastic model for reducing economic floods risk in
Yewa sub-basin, by fitting maximum annual instantaneous discharge into four
probability distributions. Daily discharge of River Yewa gauged at Ijaka-Oke
was used to establish a rating curve for the sub-basin, while return periods of
instantaneous peak floods were computed using the Hazen plotting position.
Flood magnitudes were found to increase with return periods based on Hazen
plotting position. In order to ascertain the most suitable probability
distribution for predicting design floods, the performance evaluation of the
models using root mean square error was employed. In addition, the four
probability models were subjected to goodness of fit test besed on
Anderson-Darling (A2) and Kolmogorov-Smirnov (KS). As a result of the
diagnostics test the Weibul probability distribution was confirmed to fit well
with the empirical data of the study area. The stochastic model generated from the Weibul probability
distribution, could be used to enhance sustainable development by reducing
economic flood damages in the sub-basin.
Author: O.A Agbede, Oluwatobi
Aiyelokun
Journal Code: jptsipilgg160069
