Understanding the need for
water reuse
This continuation of the National Water Resource Strategy 2
looks at the key drivers that affect water reuse choices.
By the Department of Water and Sanitation
F
ive key considerations affect the
choices related to water reuse
as an option for water supply and
augmentation:
• Water quality and security of supply
• Water treatment technology
• Cost relative to other water supply
alternatives
• Social and cultural perceptions
• Environmental considerations.
The wastewater and effluent
treatment technologies for reuse
applications are generally proven
for South African conditions. A
local knowledge base exists to
plan, design, construct, operate and
maintain a wide range of treatment
technologies. However, some of the
more sophisticated technologies, such
as advanced oxidation and membrane
desalination, have been applied to a
limited number of local projects.
The South African water industry
will need to grow capacity to confidently
implement some of the more advanced
water reuse technologies.
Cost considerations
Table 2: Applicable water treatment technologies for water reuse.
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Water Sewage & Effluent May/June 2017
Where water reuse is more cost-
effective compared to other alternatives
(such as reducing water requirements,
securing a fresh water supply, or
desalinating seawater), then water
reuse becomes an attractive choice,
provided that the quality of water can
meet the necessary requirements and
there are no important cultural or social
objections to the use of this water.
Costs are affected primarily by
water quality requirements (related
to both supply and discharge, and the
associated treatment requirements)
and the relative geographical locations
of water supply and needs. As supply
costs increase and with the introduction
of waste discharge charges, the cost