04-05-2011 - Plettenberg Bay, South Africa

DESALINATION PLANT WILL BRING WELCOME RELIEF TO DRY SOUTHERN CAPE

Following the worst drought in 138 years in the Southern Cape with no immediate respite in sight, Plettenberg Bay has been declared a disaster area. Specialised water treatment company and subsidiary of Veolia Water Solutions & Technologies, VWS Envig, has been awarded a turnkey contract to the value of R32 million by the Bitou Municipality to design, build and maintain a desalination plant able to deliver two million litres of potable water per day to alleviate the crisis.

Sea water will be abstracted from seven boreholes at a depth of 12m each, sunk close to the landmark Beacon Isle Hotel. The beach sand will act as a filter, followed by other pre-treatment phases, upon which the water will be treated by sea water reverse osmosis membranes.

After considering various options and taking into account factors such as the eco-sensitive zones on the pristine coastline, cost, land availability and infrastructure, it was decided to build the plant on a tennis court belonging to the Municipality at the hotel, where much of the pipe work and electricity supply is available.

"Originally water was to be extracted from Robberg beach, but due to shallow rock barriers, the holes did not produce enough water. Test results have indicated that the salinity of the water from the current abstraction point will be in line with the expected and falls within the scope of what the plant can treat," explains Pierre Fourie, Project Manager, VWS Envig Paarl office.

Abstracting out of the estuary and discharging into the sea are two major environmental concerns that VWS Envig are faced with. "We have opted to discharge the brine into the sea at the Blinders, where the tides and wave action over the rocks will ensure a good mix and no significant adverse effect on the environment. Over the next year, we will be drawing regular water samples to monitor the situation and to ensure that we minimise the negative impact on the estuary. This will enable us to act proactively," says Fourie.

The skid mounted sea water desalination unit used by VWS Envig for the Bitou Municipality project in Plettenberg Bay.

To further minimise the environmental impact, the building that will house the plant features a flat concrete roof that will be planted with indigenous succulents to reduce noise. "We have paid particular attention to ensure that the building is aesthetically pleasing and as green as possible," says Fourie. Mechanical energy recuperation units are used to further make the plant more energy efficient.

VWS Envig manages the project and is responsible for process design as well as the civil, mechanical and electrical work on the plant.

"Timelines are tight; the plant is due for commissioning at the beginning of December to cope with the expected influx of holiday makers over peak season in December," concludes Fourie.

As part of the 3-year operational and maintenance contract, VWS Envig will be providing training to all operators.

Veolia Water Solutions & Technologies (VWS), subsidiary of Veolia Water, is a leading design & build company and a specialised provider of technological solutions in water treatment. With over 9 500 employees in 57 countries, Veolia Water Solutions & Technologies recorded revenue of 2.5 billion Euros in 2009.

Veolia Water, the water division of Veolia Environment, is the world leader in water and wastewater services. Specialised in outsourcing services for municipal authorities, as well as industrial and service companies, Veolia Water provides water service to 95 million people and wastewater service to 66 million. With 95 789 employees in 66 countries, its 2009 revenue amounted to 12.5 billion Euros.

www.veoliawaterst.com

For more information, please contact us:

Gunter Rencken
Managing Director
Veolia Water Solutions & Technologies South Africa (Pty) Ltd
Tel: +27 11 663 3600
Fax: +27 11 608 4772
E-mail: info.southafrica@veoliawater.com

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