Aftermath of simultaneous toxic spills in the Klein Nyl River,Northern Province,South Africa

In late August 1998, a mechanical malfunction at the Nylstroom Sewage Treatment Works resulted in a massive quantity of untreated sewage flowing into the Klein Nyl River. Simultaneously, 5km upstream, a poly-aromatic hydrocarbon poison was simultaneously leaked into the same river from a 25 litre canister. These spills threatened the Nylsvley Nature Reserve, a newly acclaimed RAMSAR site, situated about 20km downstream of Nylstroom. The Limnological team of the Department of Zoology, University of the North, was asked to assist with the assessment of the effect of these spills, which resulted in a massive fish kill. A monitoring program was implemented in early September 1998 to assess the effect of these spills on the water quality of the receiving water body. The implications of the altered water quality on the aquatic biota are discussed.