The area southeast Qena was suffered from flash floods that frequently occurred during winter seasons. Best management of such floods is very important for avoiding or reducing as much as possible its hazards, in addition to increasing groundwater recharge.
The magnitude of flash floods depends up on different factors, among them, the morphometric parameters of the drainage basins, the geological and meteorological conditions of the studied area. Six drainage basins were studied through eleven hydromorphometric parameters, in addition to a trial made to estimate the quantity of runoff.
All the studied drainage basins show low bifurcation ratios and have high values of drainage densities and frequencies. These values give more possibilities for flash floods and low contribution to groundwater. With exception of the central part of W. Al-Qarn that is occupied by Nubian sandstone and characterized by a wide drainage channels and low density, thus the contribution for ground water is expected to be high. W. Al-Qarn and W. Al-Sirray are nearly circular in shape and they have high values of Relief and ruggedness number and acquire the highest values of maximum runoff. Therefore they are classified as very dangerous basins. Under such conditions, the construction of alternative barriers or loose boulder dams at the upstream parts of the drainage basins will minimize the flooding hazards and give more chance for groundwater recharge
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