Sediment management and flood protection of desert towns: effects of small catchments

Dealing with the sediment problems associated with floods poses difficult challenges to planners and managers of desert towns. Infrequent but powerful floods from even small catchments generally contain 5-10% of sediment by weight, most of it bed material. As shown by several case studies, corroborated by a simulated flash flood experiment, this sediment is capable of disrupting drainage regulators such as check dams and diversions. Based on the experience of Eilat in southern Israel, and its hyperarid surroundings, several options for dealing with the flooding/sediment hazard are evaluated. Minimal intervention with the dimensions and pathways of the natural drainage system, coupled with effective zoning regulations, should be the preferred choice in protecting desert towns.