Flood Studies in Oman and the Difficulties in Using Rainfall-Runoff Analysis

Abstract

The hydrological characteristics in arid areas are different from that of humid areas. The high temporal and spatial variability of the rainfall, flash floods, absence of base flow, sparsity of plant cover, high transmission losses, high amounts of evaporation, and evapotranspiration and the general climatology are examples of such differences in hydrological features between arid and humid areas. Hence, these differences lead to different flood characteristics. However, as most studies were carried out in humid areas, the arid areas received less attention except recently. These lead to less understanding of some of these characteristics and their effects on the obtained results when using some known methods for rainfall-runoff analysis. The floods in arid areas are very rare but when it occurs they can cause severe damages. Very high flood peaks have been recorded in different parts of arid areas. The recorded flood peaks in Oman were greater than 10% of the wards maximum. Hence, flood studies and controls became very important in all the areas that are subjected to flood risk.