Landslides: Extent and economic significance in southern Africa

Southern Africa is a region of contrasts with mainly flat, arid areas in the west and rugged, mountainous regions with a relatively high rainfall in the east. Landslides are a significant problem only in the eastern and southern coastal areas of South Africa, the western areas of Swaziland and in the rugged hills surrounding Lesotho. The rest of South Africa, Botswana and Namibia comprises limited areas with moderate landslide risk but in most areas instability is unlikely. It is estimated that the annual cost of landslide prevention, rehabilitation and associated expenses in southern Africa is about twenty million dollars (United States), incurred mostly in the eastern and southern areas of the region. The extent and processes of landslides in southern Africa are well understood and the expertise exists to deal with the design and rehabilitation of problem slopes, subject to financial constraints.