A total amount of R405 million has been set aside by the Buffalo City Metro for the upgrading and the refurbishment of four Wastewater Treatment Works (WWTWs) plants in King William’s Town to 17.5 ML/D capacity.

This project which will be done in six phases will amalgamate the Schornville, Zwelitsha, Breidbach and Bhisho WWTWs into one regional works.

Acting General Manager: Construction, Roads and Project Sandile Sojini said the purpose of combining the WWTWs was due to high demands and that the capacity of the plants could not handle the workload.

“The capacity of the plants could not handle the workload and that the biological process at the plants could not treat the water into the required efficient standards as set out by Section 21 of the National Water Act.”

“The implementation of the whole project was to establish a centralised, regional sewage area thus enabling the decommissioning of the dysfunctional WWTWs and improving the level of sewage transport and treatment achieved across the focus area.”

“It was necessary to construct a network of bulk sewers to facilitate the transfer of sewage from smaller plants to the Zwelitsha plant with associated structures such as pipelines bridges, screens and pumps stations.

Reducing operational cover

Sojini said the amalgamation of the plants will reduce the operational cover over the life of the plant and that upgrading all smaller plants would be more expensive.

“The project will focus on the Schornville, Zwelitsha, Breidbach and Bhisho WWTWs and that the later be upgraded as regional 35MI/day capacity WWTWS and the remaining smaller plants decommissioned.”

He added that phase one of the project has kicked off and that 30 percent of the work has been completed.

Phase one which has ate away an amount of R15 million of the budget consist of seven kilometers of 700mm – 80mm diameter gravity outfall sewer taking the raw sewage water from Schornville Water Treatment Plant to Zwelitsha WWTWs.

In Phase two the upgrading of the works will be done in two phases with the first phase consisting of upgrading of the works to 17.5 megalitres per day.

Infrastructure to be upgraded

The following new main infrastructure will be constructed during this phase:

• A new inlet works with an odour control building
• A division box to allow for dividing flows equally to the reactors.
• A new 24 000m³ Reactor with Anaerobic, Anoxic and Aerobic zones with necessary recycling streams
• A division box to divide the flow from the two reactors to 6 x Secondary Settling Tanks (SST’s)
• 3 x 29m diameter SST’s
• 1 x Chlorine contact tank
• Return Activated sludge (RAS) screw pump station
• Drainage Pump Station
• Peak flows balancing Tank
• Sludge dewatering building
• Administration Building
• Plant operators living contours
• Chemical dosing and storage building
• Related Civil Engineering Structures – that is roads, stormwater and  washwater