Desalination
Desalination
plant resolves
water crisis
In Lamberts Bay
I
f you live in a coastal town on the Cape coast,
you may be familiar with the pressure on the
water system in the holiday season.
Seawater desalination, however, is a viable choice for coastal
regions because it provides a sustainable, constant source of
water year-round.
Lamberts Bay, a town about 280 kilometres from Cape Town
- along the Cape West Coast, in Cederberg - has only six
boreholes to supply water to the entire region.
To resolve this dilemma, the Department of Water Affairs
(DWA) and the Cederberg Muncipality first considered
two possibilities: provide additional boreholes; or install a
61-kilometre pipeline feeding from the Clanwilliam Dam.
Investigative studies, however, revealed the pipeline would
not guarantee a sustainable water supply and test boreholes
exposed overly excessive iron and manganese content in the
water. The DWA and the town’s municipality therefore decided
to commission a new desalination plant adjacent to the town’s
existing water purification plant.
Solution
The Lamberts Bay desalination plant, which came into
full operation during the second quarter of 2014 at an
approximate cost of R 17 million, uses reverse osmosis (RO)
membrane desalination to separate salt from seawater. RO is
realised by forcing seawater through a membrane using high
external pressure to separate it from the salt, and is one stage
in the process enabling the plant to provide 1.7 mega litres
of potable water per day. The plant’s infrastructure has been
designed to accommodate future expansion of up to 5 mega
litres per day, providing the c \X