Page 111 - SAICE book proof 2 LATEST JULY 2014

s a i c e
WESTERN CAPE PROVINCE

Due to water pressure from the 110 m high reservoir, ◊ Below: Olifants river Bridge
damage to the water fittings in the town was common, ◊ Bottom: Swartklip Interchange
causing fresh water to flow to sewers and into the sand
at about 1 200 m³/h. In 2001 a world-class and award-
winning solution was found and implemented in the
form of a pressure reduction facility. This civil engineer-
ing innovation is saving the city about R27 million per
annum and it cost only R2.5 million. Since the building
is in the middle of the town, an architect, Hannes Botha,
was approached and he designed the valve chamber to
resemble a very attractive traditional building at no cost
to the project.

34°02’25.00” S, 18°40’40.00” E

13. Cape flats Wastewater Treatment Works,
also known as the False Bay Ecology Park at Strand-
fontein is about 500 ha in size. It is one of Cape Town’s
largest sewage treatment works. Even though it is not a
natural wetland, the ponds are one of Africa’s important
bird areas and are deemed to be one of the ten most
important habitats for wetland birds in South Africa.
Observers have counted 30 000 birds in one summer
period and more than 200 water bird species have been
recorded so far including African fish eagles, flamin-
gos, pelicans and many types of ducks. Even nine bird
species that are threatened with extinction have been
seen at Strandfontein, for example the near threatened
great white pelican (Pelecanus onocrotalus), African
black oystercatcher (Haematopus moquini) and greater
flamingo (Phoenicopterus roseus), and the vulnerable through this strategic point. Swartklip and many of the
African marsh harrier (Circus ranivorus). other interchanges are modern marvels of smooth con-
crete curves that not only allow free flow of traffic but
Who would have thought that civil engineering is for the also delight the eye, displaying the aesthetic appeal of
birds as well? civil engineering structures.

34°05’ S, 18°31’ E 34°02’49.56” S, 18°38’28.89” E

14. Olifants River Bridge on the Sishen Sal- 16. Sishen Saldanha railway line and Saldanha
danha railway line is one of the major structures on Bay Iron ore terminal at the harbour is a major
this line and is in the form of a 1 035 m long viaduct. contributor to the commodities exports of South Africa.
The long and proud history of railways around southern
Africa has been expanded by this modern facility. The
31°30’55.74” S, 18°17’06.74” E 861 km long railway line connects iron ore mines near
Sishen in the Northern Cape with the port at Saldanha
Bay in the Western Cape since 1976. It does not carry
15. Swartklip Interchange is only one of many any passenger traffic. Although it is a single electrified
interchanges on the freeway and highway systems of line, about 20 long passing loops are spaced along the
the City of Cape Town. The very necessary Koeberg In- route to facilitate continuous operations.
terchange upgrade had very difficult conditions as it had
to be done while traffic flow had to remain unaffected Starting out at 1 295 m above sea level at Sishen, the

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