South Africa has historically managed water very poorly, despite it being in the top bracket of dry countries worldwide.
To the last drop
Increasingly, the world
is researching ways to
obtain the last drop of
potable water out of
everything, from recycled
water to human waste –
with differing results.
By Kim Kemp
26
T
he word ‘wastewater’ is inclined
to leave a bad taste in one’s
mouth as it is generally viewed
as a by-product and something to
be discarded. Yet increasingly, the
public is moving past this perception,
and turning wastewater into potable
water is gaining traction, easing the
strain of accessibility to this resource
in water-scarce countries.
Wastewater definition
Wastewater comes from a
combination of domestic, industrial,
commercial or agricultural activities;
from ordinary living processes,
including bathing, toilet flushing,
laundry, dishwashing, and so on. It
Water Sewage & Effluent November/December 2017
can originate from surface runoff or
storm water, as well as from sewer
inflow or infiltration.
As a rule, wastewater is broken
into two categories, depending upon
the source:
Greywater: is from sinks, washing
machines, and bathtubs. It contains
lower levels of contaminants than
blackwater and is easier to treat and
process. It can even be used directly
in gardens, if there are no harmful
chemicals present, like soap and
detergents, that can harm the plants
and the soil. Recycled greywater
can also be used for irrigation and
in constructed wetlands. If the
greywater is from the sink, food