The capacity of the Ogunjini water treatment works, owned by the eThekwini municipality, has been increased from one-million to three-million litres a day to address the longstanding water shortages in the area, eThekwini Water and Sanitation civil engineer and project manager Lungelo Nzama confirms.

The upgrade was commissioned on May 8, 2026, and has been completed. The plant supplies the Ogunjini, Mjoji, Oakford and Osindisweni areas, in KwaZulu-Natal.

The project was necessitated by significant population growth in the catchment areas, together with the historical seasonal underperformance of the existing facility.

Nzama explains that the slow sand filtration process relies on relatively low filtration rates and requires the appropriate maintenance of the filter beds, with deterioration in filter performance or cleaning requirements further reducing effective production capacity.

Consequently, the upgraded plant will operate as a pressurised filter treatment plant, incorporating chemical coagulation and flocculation, as well as pressurised filtration.

The new process improves the removal of suspended solids and turbidity, particularly when raw-water quality deteriorates during periods of rainfall or increased turbidity. It also provides greater control over contaminants, supporting more consistent water quality.

The increased capacity also provides greater flexibility to respond to daily and seasonal fluctuations in water demand, while chemical treatment allows for the process to be adjusted when raw-water characteristics change.

However, one of the key challenges during construction was carrying out the upgrade while keeping the existing Ogunjini water treatment plant operational.

“Construction activities were therefore coordinated around the existing treatment process to avoid interruptions to water production. Connections between the new treatment facilities and existing infrastructure required careful planning of tie-ins, shutdowns and commissioning activities,” Nzama elaborates.

Where temporary interruptions were unavoidable, activities were sequenced to minimise shutdown durations and were coordinated with the operations team to limit the impact on water production.

Upgrades

The upgrade included modifications to the existing abstraction and river intake works; the construction of a new raw-water pipeline; upgrades to power, control and instrumentation; and modifications to the existing raw-water balancing tanks and on-site clear-water storage.

A 500 000 ℓ potable-water storage tank was also installed on site as part of the upgrade.

“The upgrade’s incorporation of modern systems gives operators greater visibility and control of the treatment process while reducing reliance on manual intervention,” Nzama adds.

The chemical treatment system provides greater control over chemical dosing, while improved monitoring of mechanical and electrical equipment allows for operational problems or equipment failures to be identified earlier.

“Based on average consumption of 700 ℓ per household a day, this [upgrade] represents a theoretical supply capacity to about 4 285 households,” he concludes.