Mysterious fish deaths spark investigation at Nandoni Dam
The Department of Water and Sanitation probes fish mortality at Nandoni Dam, urging communities not to consume the dead fish.

LIMPOPO – The Department of Water and Sanitation (DWS) is investigating the recent fish mortality incident at Nandoni Dam and the Luvuvhu River near Tshitomboni and Tswinga villages.
The department received reports of dead fish on the evening of December 19 and collected water samples at the affected sites on December 20.
DWS spokesperson Wisani Mavasa said the samples were analysed at two accredited laboratories, Muratho Laboratory and Capricorn Veterinary Laboratory.
“Preliminary results showed that all water quality parameters, including dissolved oxygen and chemical oxygen demand, were within acceptable limits as per prescribed standards. Therefore, preliminary results indicated no significant water quality deviations to explain the fish mortality. Samples of dead fish were preserved for pathological analysis, which commenced when laboratories reopen this week.”
She said that this should enable the department to identify the cause of the fish mortality.
“So far, the department can confirm that only one type of fish species out of approximately five species in the affected 1km stretch of the Luvuvhu River was impacted. Additionally, on December 21, the department conducted inspection at the Thohoyandou wastewater treatment plant and three associated wastewater pumps as well as several manholes to exclude sewage overflows and spillages. None of these were detected. Further water samples were collected at Tshitomboni pedestrian bridge on December 22, to test for possible oil contamination after a substance resembling oil particles was observed floating on the river water. Although the substance could be oil of decaying dead fish, the department wants to ascertain this in a scientific way,” she added.
The department urged community members not to consume or sell the dead fish, as it may pose serious health risks.
“The department remains committed to transparency and will provide further updates as additional test results and findings become available. The public is further advised not to swim in the Nandoni Dam or drink water from the watercourse as it is raw and untreated and not fit for human consumption. A detailed statement will be issued once the investigation has been concluded,” said Mavasa.
Nandoni Dam is the one that the Giyani Bulk Water Project will be receiving water from, for all 55 villages under Giyani.