The Civil Engineering Contractor November 2018 | Page 30

INSIGHT
One of the project’s challenges is working in a harsh mountainous environment.
Phase II is expected to ensure a
reliable water supply to South Africa
by 2026 that will meet the demands
of the Gauteng region, increasing the
current supply rate of 780-million
m 3 /year from the LHWP to the Vaal
System by approximately 465-million
m 3 to make a total of 1 270-million m 3 /
year. Phase II is equally significant for
Lesotho. The existing 72MW Muela
hydropower station was built under
Phase I of the project. Under Phase II,
the hydropower generation capacity
of the scheme will be increased. The
1 200MW Kobong Pumped Storage
Scheme, or an alternative scheme as
articulated in the bi-national Phase
II agreement, is currently still in the
feasibility phase.
The current estimate is that the
cost of Phase II at completion will
be in the order of R25-billion for
the South African water transfer
component alone, with the Lesotho
power generation component not yet
quantified. South Africa will bear the
costs related to the water transfer
component, while Lesotho will bear
28 | CEC November 2018
the costs related to the hydropower
component and its related social and
environmental costs.
“The hydropower scheme is
still in the feasibility stage, along
with proposals to use the water for
ancillary developmental projects,
whether irrigation or aquaculture,
such as the trout export operation
already established during Phase I
at Katse Dam. From the feasibility
stage it was envisaged that we would
employ two tunnel boring machines
(TBMs) drilling approximately 15km
of tunnels from opposite ends to
meet in the middle, with the western
8km leg envisaged to be a drill-and-
blast. An interesting aspect of the
project is that the western part of
the tunnel end consists of an existing
dam [Katse] already full of water, so
we will have to have an interesting
entry beneath the water. For the
hydropower component, we’ve had
to study the pump storage option
and conventional options, and
these are ongoing,” says Tente. The
project authorities recently received
a recommendation regarding the
options for hydropower and decided
to defer the power storage option and
continue with the conventional option
to a bankable feasibility.
To date, he says, about 27 different
contracts have already been signed for
consultancy services since the bilateral
agreement was signed in 2011,
relating to engineering, environment,
construction, and various hydropower
services. Tente notes perceptions of
conflicting interests between Lesotho
citizens and South African citizens,
given that Lesotho wants to maximise
power generation and South Africa
is keen to store water for greater
water security.
“We’re looking at the two schemes
(water transfer and hydropower)
being commissioned at the same time.
We have an Advanced Infrastructure
Programme: Because the project is
going to be in the heart of the highland
(where currently there is no modern
infrastructure), we need to create
appropriate infrastructure in terms of
housing in the form of a construction
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