The Civil Engineering Contractor January 2019 | Page 26

TECHNOLOGY
Damming the Vaal River has resulted in average river flows of 50%, when it could on occasion have fallen to 10% in a year.
and adopted a multifaceted policy
response that has enabled the city
to reduce per capita consumption
by roughly one-third (from just
over 700ℓ/day in 1989 to less than
500ℓ/day
in
2015). This
multipronged approach involved
instituting tiered water pricing
(higher rates for larger consumers),
implementing new building codes
(reducing irrigation for landscaping
and mandating efficient utilities in
commercial spaces), encouraging
the collection of rainwater, and
offering a slew of incentives for
private individuals to invest in water-
efficient appliances. The result is
that total consumption in the city
is roughly the same as it was in the
late 1980s, despite its population
growing by about 25% over the
same time period.”
Desalination: These plants are
expensive, and the one existing plant
we have in Mossel Bay is apparently
not in use, as it is highly energy
demanding. There are believed to be
10 small (community-based) plants
dotted along the coast. However, the
advantage of this strategy is that with
24 | CEC January 2019
more and more desalinated water in
circulation, there will also be more
wastewater to reclaim. Greenwald
says that what has fundamentally
changed in Israel is its sources of
water: 15 years ago, 77% of its water
supply was from natural sources
and today, that per cent of natural
potable water has fallen to 35%.
PPPs: Speaking at a seminar on
water, MDA Consulting senior
associate Natalie Reyneke says
that in an environment of a
DWS without budget for water
infrastructure such as desalination
plants, such projects would have
to be bottom-up driven — “the
private sector must create them
and fund them”. At present, there
are about 30 PPPs in South Africa,
but none for a desalination plant
and only one for waste treatment
plant in the implementation phase,
which is a waste treatment plant in
eThekwini. There is also alternative
waste treatment methodology in
Johannesburg in its feasibility stage.
Given the high cost of energy
associated with desalination plants,
Reyneke described the plant
design as one of the biggest project
risks (alongside the need for land
expropriation and environmental
risks),
requiring
acceptable
technology and revenue streams
that make it profitable. “The project
would be predicated on a certain
revenue stream, and the financiers
would want to secure that revenue
stream. This tends to raise the risk
profile, as any construction delays
may result in further funding being
required, and with this comes the
potential for high delay penalties,”
says Reyneke. It is these factors,
she says, which make municipalities
question the PPP model versus
doing the project themselves. It is
municipalities that would typically be
the procuring agency for PPPs as a
solicited offer. There is also scope for
non-solicited offers from contractors.
Municipal capacity: Elsewhere
in this issue, Chris Campbell, CEO
of CESA, says business and the
financial sector are currently looking
at “how might they make sensible
investments to improve capacity at
municipal level”. (Read more on
page 38.)
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