R1.4bn bulk water treatment plant completed
30 August 2018 | Web Article Number: ME201811462
VEOLIA Water Technologies South Africa recently completed its contract for the 55 Mℓ/day potable water treatment plant in the iLembe District in KwaZulu-Natal.
Part of the Lower Thukela Bulk Water Supply Scheme (LTBWSS), the plant, constructed at a cost of R1.4 billion and funded by Umgeni Water and the Department of Water and Sanitation, will eventually supply approximately 340 000 people in the iLembe district with potable water, from inland of Mandini to Ballito in the south. This will be the first time many of these people receive a reliable supply of safe drinking water.
In what is one of the largest municipal potable water treatment plants undertaken by Veolia South Africa, the company was responsible for supplying the required mechanical and electrical components for the treatment plant as well as for the customised abstraction works that will pump water from the river.
“The remote location of the construction site required careful planning and logistical accuracy amongst each of the project stakeholders,” explained Pierre Michallet, Senior Project Manager, Veolia Water Technologies South Africa. Veolia and its EPCM partners as well as the primary stakeholders of the project (Umgeni Water, engineers and the civil contractors) worked in close collaboration throughout the project to ensure a successful execution and delivery.
Raw water is abstracted from the uThukela River through a boulder and gravels traps system that prevents large matter from being deposited into the water treatment works. The stream is screened as it is split into four canals designed to allow finer sediments and sand particles to settle.
Then, the flow is further pumped from the low lift pump station up to the beginning of the water treatment, the hydrocyclone. Additional filtering for sediment, grit, organic matter and heavy metals then takes place via gravity using clariflocculators, the Pulsator pulsed sludge blanket clarifier and sand filtration. Underflow sludge accumulated across the treatment processes is dewatered through decanter centrifuges.
As part of the CPG proposal, Veolia was responsible for fostering and developing relevant professional and technical skills among the region’s communities that can be utilised in the operation and maintenance of the water plant. A coordinated recruitment plan to identify locally trained engineers, mechanical and electrical fitters, boiler makers, and other vocations that can be used in the plant’s operation.
Provision has been made to scale the plant’s potable water production capacity from 55 up to 110 Ml/day, should it be required in the future.