ABSTRACT
Several studies have been conducted in the southwestern region of Saudi Arabia to determine channel losses and groundwater recharge from wadi beds. Binnie & Partners (1975) concluded that bed infiltration was as high as 95% of the total runoff in one of the wadis in the Kingdom over a 50 km reach. More recently, Dames & Moore (1988) and Walters (1990) indicated transmission loss values of 5612, 27, 174 and 186,000 m3/km for wadis Tabalah, Habawnah and Yibe respectively. These studies, and one more recently conducted by Abdulrazzak, et al. (1991), indicate that the magnitude of transmission loss is influenced by the flood hydrograph, channel and soil characteristics. These parameters act interdependently and make it difficult to arrive at simple analytical solutions for estimating channel loss and recharge. Few studies have addressed the subject of infiltration from wadi channels using analytical or numerical techniques; examples are Abdulrazzak & Morel-Seytoux (1983), Freyberg (1983), Morel-Seytoux, et al. (1990), Guzman, et al. (1989) and Parissopoulos & Wheater (1991).
