TEMPORARY COFFERDAM TO BE BUILT AT VOORBAAI DESALINATION PLANT SITE
A temporary cofferdam will be built in the sea at Voorbaai for the laying of the inward-bound seawater pipeline and outward bound brine pipeline for the R200-million seawater desalination plant being built at Mossel Bay, the Mossel Bay Municipality has announced.
The project has been necessitated by the severe drought, the worst in 132 years, experienced in the Southern Cape at present and the fact that Mossel Bay’s main source of water, the Wolwedans Dam, may run dry within the next few months if it does not rain before then. The plant will supply fresh water to the Municipality as well as PetroSA during times of water shortages and peak water usage periods, such as the year-end holiday seasons, if necessary.
The desalination plant is designed to produce 15 megalitres of potable water a day. PetroSA, which is contributing R80 million to the cost of the project and on whose property the plant will is located, is entitled to a third of its production. The rest of the production will be available for the Municipality.
The cofferdam will stretch approximately 155 metres from the beach into the sea and it is required to stabilise the environment so that the pipe lines can be laid. It will be built by extending a sand berm from the beach out to sea and using sheet piles to stabilise the walls of the dam.
Construction of the cofferdam is schedule to commence within a week or two and it will remain in place until the pipelines have been laid. The pipeline project is schedule to be completed by the middle of November 2010.
Once the pipelines have been laid, the cofferdam will be demolished completely and the area be restored to its former state.