Historical events and land use changes shaping the Isipingo river catchment, Kwazulu-Natal, South Africa

The Isipingo River and its catchment is regarded as one of the most severely impacted in KwaZulu-Natal. A series of highly publicized pollution episodes in the local media and general public outcry have cemented the impression that the degradation of the system is largely anthropogenic. This study identifies the significant land use changes following an extensive review of printed media, documentaries, photographs, prior research and interviews. The changes identified include development of a major airport, diversion of the Umlazi River, construction of river diversion works system and canalization of the lower Isipingo River. The developments have contributed to a drastic reduction in mean annual runoff from 102 to 3 million m3/year, exacerbating estuary mouth closure, and necessitating the construction of twin pipes at the mouth to maintain tidal exchange. Intensive residential and industrial development on the river floodplain has led to the removal of indigenous and riparian vegetation. The historically poor water quality in the Isipingo River and Estuary has been related to inadequate sanitation facilities and illegal discharges of industrial effluent. The deterioration of Isipingo River system demonstrates the consequences of improper planning and over-utilization of the catchment together with poor application of regulations pertaining to the environment. This paper documents the historical land use changes and events that have shaped the Isipingo catchment and ultimately influenced the quality and quantity of water over a 172 year period from 1840 to present day.