ABSTRACT
This paper focuses on modelling fluid flow processes in the unsaturated zone beneath surface spreading artificial recharge facilities. A sixty layer model has been developed to simulate flow from a recharge basin through the unsaturated and saturated zones. Clogging of in-situ pore space is the major limiting factor in sustainable artificial recharge operations. Clogging rates have been simulated in the surface layers of the model by a power function. Several model scenarios have been generated with uniform and layered hydraulic conductivity soil media. Results of modelling indicate that the majority of recharge occurs in the initial 6 days after flooding of the basin. After this initial period recharge rates are reduced significantly by clogging. An understanding of these key parameters can help in generating and calibrating accurate numerical models. The data derived from these models can be used in management of artificial recharge operations.
