Water and Sanitation on Tzaneen dam structure not at immediate risk amidst heavy rains

The recent heavy rains in the Tzaneen Dam catchment have led to the dam spilling which has raised numerous concerns. Several reports on social media platforms are circulating, claiming structural damage at the Tzaneen Dam wall.

The Raising of Tzaneen Dam Wall is one of the mega projects being implemented by the Department of Water and Sanitation (DWS).

The existing dam wall was reduced by 4m in preparation for the raising of the dam and the construction of a new spillway structure is underway. This temporary reduction in dam wall height is currently beneficial, as it allows water to flow over the reduced dam wall.

In addition to the spillway discharge, diversion pipelines remain operational and are actively monitored by the appointed Professional Service Provider (PSP) and controlled by DWS. Controlled releases are also being undertaken through the sluice valves under continuous supervision.

Since the dam is under construction (raising the wall to increase the storage capacity), several areas have been exposed but were not completed by the onset of the rains. Some temporary measures were implemented to mitigate the impact of rainfall-induced surface erosion. In some places, the downstream slope protection (paving bricks) were removed as part of the approved construction works prior to the rainfall event. Such areas will naturally suffer surface erosion from intense and prolonged rainfall.

Following inspections after the rainfall, localised downstream embankment erosion was identified and in response, the Engineer issued immediate instructions for emergency temporary protection works. These interventions are temporary emergency measures intended to stabilise the embankment and preserve structural integrity until permanent works can be safely implemented.

The Approved Professional Person (APP) and the PSP have confirmed that there is no immediate risk of structural failure of the dam, nor any threat to downstream homesteads. The dam remains operational and is being closely monitored in accordance with DWS operational procedures. The Emergency Preparedness Plan (EPP), compiled and updated in 2025, remains in place and can be activated should conditions escalate.

The PSP's technical team remains on site and conducts daily inspections to assess the structural integrity of the dam. Additional corrective measures will be implemented once site conditions are safe to allow work in wet environments. Once rainfall subsides, a detailed assessment will be undertaken to determine the extent of damage and the time lost.

For more information, contact:

Wisane Mavasa, Spokesperson for the Department of Water and Sanitation
Cell: 060 561 8935
E-mail: [email protected].

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