Evaluating of Efficiency of Empirical Formulae Based on Grain-Size and Infiltration Equations for Estimating Sediment Hydraulic Conductivity (Case Study: Jarmeh Flood Spreading System, Khuzestan Province)

Hydraulic conductivity is an important parameter for the control of water flow through porous media. Hence, accurate estimation of the parameter is important for evaluating of flow exchange between surface water and groundwater. In this study, 12 empirical formulae based on grain-size and 4 infiltration equations were used for estimating hydraulic conductivity on 3 sites in Jarmeh flood spreading system, Khuzestan Province. Results were evaluated using measured hydraulic conductivity by double rings infiltrometer. The results of the empirical formulae showed that 9 formulae were overestimated or underestimated and 3 formulae were close to measured values. Hazen formula give the largest overestimation and Slitcher formula give the largest underestimation and Shepherd formula is the best one. Generally, in order that the empirical formulae to be applicable, the C coefficients should be calibrated. The results of the infiltration equations showed that all of 4 equations were successfully estimated hydraulic conductivity and there are no significant differences between them. Among the equations, Kastiakov and Green-Ampt were the best of them.