The Department of Water and Sanitation (DWS) on Monday warned residents living upstream of the Duzi and Mngeni rivers, the Inanda dam and surroundings not to use water from the resource until further notice.

This followed a spillage a week ago at Willowton Oil, in Pietermaritzburg, that has worked its way downstream into the Mngeni river and the Inanda dam.

The DWS reported that the collapse of two tanks, one containing fatty acid and the other caustic lime, at Willowton Oil last week had resulted in a crude oil pipe being crushed and a subsequent leakage into the water resource.

The DWS said an estimated 1 600 t of product spilled within the Willowton premises and flowed into the Baynespruit river through the stormwater drains.

Willowton Oil, in a statement post-spill, said its main focus was to fully ascertain the environmental impact and to implement the containment and effect the necessary rehabilitation required.

Spilltech and Drizit were immediately dispatched to undertake clean-up of both the affected water resources and the operational area.

“The companies have managed to contain the spillage at Grimthorpe Bridge and the clean-up of the Duzi river is currently under way and progressing well,” the DWS said.

As the DWS in KwaZulu-Natal investigates the Duzi river pollution, 100 people are currently cleaning different sections of the river from Baynespruit, Msunduzi and further down to Inanda dam.

Umgeni Water released water on August 14 from the Henley dam to dilute the spilled product that escaped from Baynespruit into the Msunduzi river before the placing of blooms.

The dilution managed to bring the pH down to 8.5 from 10.78.

“Further improvement in the water quality results is expected as the clean-up progresses,” the department assured citizens.

A task team, comprising the KwaZulu-Natal Department of Economic Development, Tourism and Environmental Affairs, the DWS, Umgeni Water, the Msunduzi municipality, managers of the clean-up companies and Willowton representatives, is monitoring the clean-up progress to ensure compliance with the environmental legislation, including by-laws.

An independent environmentalist has also been appointed to ensure compliance with all the environmental legislation and to submit all the reports required within the specified timeframes, while Ground Truth has been appointed to assess the impact on the water resources and to effect all the best practical environmental remediation measures.

The department is also discussing possible measures for implementation to clean the affected rivers and to prevent the migration of the spilled substance.

Continued monitoring will take place through water sampling, site inspections and necessary meetings, with a report to be forwarded to the relevant authorities.

Bio-monitoring will also be undertaken on different points of the affected water resources.