The Impact of the Construction of a Dam on Flood Management

Abstract

A possible strategy to mitigate the effects of flooding from an area identified as having high runoff potential will reduce the volumes of water that overflow the drainage area and build a system of a storage location in the coastal city of Tangier. The study is based on two main axes: (i) the extreme flow frequency analysis, using eight probability laws adjusted by the Maximum Likelihood method, and (ii) the estimation of the flood outflows at the dam outlet using the routing method in order to assess the effect of detention dams on water flood. Annual (Maximum) series based flood sampling procedure is adopted for constructing the Flood Frequency analysis. A numerical comparison of AIC criteria and BIC has allowed a proceeding to the selection of the most fitted law distributions. The result shows that the Gumbel law is best adapted to the predetermination of the extreme flow estimation in the Mghogha watershed for different return periods. The reservoir routing method along with rainfall-runoff processes were applied by the mean of the HEC-HMS model. The model was run under two different scenarios. Scenario 1 simulates the Mghogha basin with the absence of the reservoir. Meanwhile, scenario 2 simulates the same basin by taking into account the existence of the Ain Mechlawa reservoir within different return periods of from 2 to 200 years. Peak discharges downstream have been dramatically attenuated and water volumes have been decreased with the prolongation of the return period. For the 100 and 200 return periods, the peak discharge of flood reduction for scenario 1 and scenario 2 were 52.06 and 52.17 %, respectively, and for the flood volume was 22.46 and 22.82% respectively. Finally, the results of investigations showed a good performance of the model in the estimation of outflow peak discharge of the Ain Mechlawa Dam. Doi: 10.28991/cej-2021-03091658 Full Text: PDF

Numerical Modeling for the Effect of Soil Type on Stability of Embankment

“…The continuous erosion process transports sediment materials along the foot of the dike. Shapes of breach channels during the erosion process are triangular, rectangular, and trapezoidal [9].…”

A Stochastic Conflict Resolution Optimization Model for Flood Management in Detention Basins: Application of Fuzzy Graph Model

“…Although stochastic models ensure that certain levels of unpredictability and uncertainties exist in inflow hydrographs that pass through the detention basins, which are significant in combating the risks of floods [42][43][44][45], they have received little attention in the literature. Moreover, stochastic models are more beneficial for designing detention basins than deterministic models because they supplement uncertainties inherent in natural flood events since floods are stochastic processes [46][47][48]. Considering uncertainties inherent in the system, a commendable optimization algorithm, the so-called non-dominated sorting genetic algorithm-III (NSGA-III), can efficiently model complicated hydrological systems such as detention basins and their sub-structures during floods using efficacious uncertainty assessment techniques, namely conditional value-at-risk (CVaR) and non-linear interval number programming (NINP) approaches.…”

Impacts of Dam Operation on Vegetation Dynamics of Mid-Channel Bars in the Mid-Lower Yangtze River, China

“…Two possible changing patterns that vegetation of MCBs downstream a dam would be expected to follow are: (1) The vegetation area may shrink [3,40]; according to the classical species-area relationship, the reduction of the MCB area could result in vegetation decreasing [41,42]; (2) the MCB vegetation area may expand because flood disturbances (in terms of flooding time and frequency) would be weakened by dam operation [43][44][45]. Yet, little evidence has been reported to date on this.…”