ABSTRACT

The Xai-Xai area, located at the bottom of a vertical relief of 800 metres draining the land from four countries, Zimbabwe, Botswana, South Africa and Mozambique, is prone to very fast flooding. One of the worst floods in the area happened in 2000 due to the Cyclone Eline. Prior to the cyclone hitting the area, heavy rainfalls and a tropical storm brought 700mm of rain over two days, resulting in 4-8 metres of flooding. The flow of the Limpopo River at Xai-Xai at the time of the storm was estimated at 10,000 m3/sec (10 times the normal rate), breaking through dykes and resulting in flash flooding (Christie and Hanlon 2001). It is estimated that 2 million people were affected by the floods (Christie and Hanlon 2001), but at the time the British Broadcasting Corporation reported 7,000 people near Xai-Xai were trapped in trees – some up to several days – and approximately 700 perished (BBC 2000). This was the worst flood since 1997, when the water reached 6.07m or 1.77m above flood level. Although a similar flood had occurred in 1915, which reached 5.7m or 1.4m above flood level, the area had experience bad floods quite frequently (1955, 1967, 1972, 1975 and 1981).