On the 8th of April 2024, the Compliance Monitoring and Enforcement Unit (CME) of the Mzimvubu- Tsitsikamma Proto Catchment Management Agency received a complaint from the media regarding a fish kill incident that allegedly occurred in Dorchester Heights, Northbend Lane Street, Lower Ridge in Nahoon River under the Buffalo City Municipality.

A preliminary assessment was conducted to check the land use within the locality of the incident and samples to determine the quality of water were taken at Horseshoe Bridge, upstream of the Dorchester low-lying bridge and downstream of the Dorchester low-lying bridge, and the Dorchester low-lying bridge.

A further follow-up investigation, which included officials from Resource Protection was conducted on the 30th of April 2024. During this investigation, sampling for macro-invertebrate, fish and physico-chemical parameters was conducted.

Fish respond quickly to a multitude of physical, chemical and biological changes within the aquatic environment and as such, they are also used as biological indicators of river conditions. Water quality samples were collected to determine the presence and concentration of any chemical contaminants in the water.

This investigation conducted on the 30th of April 2024 revealed that the presence of foam and hyacinth downstream, at the Dorchester low-lying bridge. The river flow had increased significantly due to recent rain. Meanwhile, water quality parameters assessed on the 30th of April 2024, were largely within the target water quality ranges. The parameters which exceeded the limits cannot be the determining factor for fish kill because the analysis requires a case and site-specific approach, which includes historical background data of the site, specifically relating to the geology and quality of the Nahoon River, and therefore, based on the water quality results of the fish kill at Dorchester Heights, same cannot be associated with the pollution.

In addition, the investigation concluded that the catchment had experienced rain the previous week, which might have cleared the effects of the reported pollution, no signs of pollution can be associated with the East London abattoir as suspected by the individual who reported the incident. Proliferation of algal blooms like water hyacinth can reduce oxygen in water and this can result in fish suffocation and death. This could have been another cause of the reported fish kill but this could not be verified during investigation as the hyacinth might have been washed away and reduced by the previous rain.

The Department recognises and understands the seriousness of the negative impact pollution has on the ecosystem and local communities. The Department is committed to ensuring that water resources throughout the country are protected and will act against any individual that pollutes.

For more information, contact 
Andile Tshona, Acting Spokesperson for the Department of Water and Sanitation 
Cell: 073 566 3345 
E-mail: tshonaa@dws.gov.za