Transmission Losses in Arid Region

Hydrographs of ephemeral streams in arid and semiarid regions usually decrease significantly in magnitude downstream, unless augmented by tributary flows. This process, termed transmission loss, is important not only in its obvious effect on flow reduction, but also as a source of ground water recharge to underlying alluvial aquifers. Most of the previous work in transmission loss was carried out on the semiarid regions of the United States. In this paper, three regression equations were developed for relating transmission loss to channel characteristics for an arid region in southwest Saudi Arabia. One of the equations seems to be reliable predictor of small losses associated with small upstream volumes. The other two equations were better predictors for large losses associated with large upstream volumes. Transmission loss data were also compared with some previously published. Although there was some scatter, the data is generally consistent with that previously published. This paper also adds to the data base of published data on transmission loss.