Moisture content data from an infiltration experiment undertaken in the dry main stream bed of wadi Habawnah, south-west Saudi Arabia, are reported. A simple experiment enabled hydraulic properties of the multi-layer soil profile to be inferred through inversion of an unsaturated soil water simulation model. The results indicate a heterogeneous but highly transmissive profile and suggest that significant groundwater recharge will occur from ephemeral wadi flows, at least at that location.