Some of the ecological effects of a small inter-basin water transfer on the receiving reaches of the upper Berg River, Western Cape

Inter-basin water transfer (IBT) is defined as the transfer of water from one geographically isolated river catchment, sub-catchment or river reach, to another. Thus, one river becomes a donor, and another the recipient. They are joined by a range of possible transfer routes. In many cases either or both the donor and recipient rivers are impounded. The volumes of water transferred and the operational criteria for IBT schemes vary considerably. This study produced a review of the literature dealing with the ecological (physical, chemical and biological) effects of IBTs. The review highlighted the fact that much of the information available is conceptual, and provides few data collected from systems affected by transfer schemes. The main objective of this study was, therefore, to collect data from a donor and recipient river of a small IBT scheme in the Western Cape, the Riviersonderend-Berg-Eerste River Government Water Scheme (RBEGS). The donor river, the Riviersonderend, is impounded by the Theewaterskloof Dam. Water from this reservoir is transferred through a tunnel to the upper reaches of the Berg River, and then on to the Cape Metropolitan Area (CMA). Approximately 38-45% of the water utilised in the CMA is transferred from Theewaterskloof. The release of water into the upper Berg is f, for irrigation in the upper catchment, and for use by a rainbow trout farm downstream of the outlet.

Grantor dc:publisher.institution

Department of Biological Sciences

Year dc:date.issued

1998

Author dc:creator

• Snaddon, Catherine Diana)

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/17962

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/17962