Irrigation of newly seeded sports field at a school in Delft.
Boring for water
Cape Town’s dire water supply is getting help from relatively quick
and expanded use of local groundwater resources.
A
s summer has ended and
winter rains are delayed,
engineers and scientists at
SRK Consulting’s Cape Town office
say the aquifers in the greater Cape
Town area could offer some respite
if current conditions continue, by
taking pressure off potable water
demand — excluding the conventional
exploitation of the Table Mountain
Group Aquifer.
Says SRK corporate consultant
Peter Rosewarne, “Groundwater
sources such as the Cape Flats
Aquifer and the Newlands Aquifer
could be accessed relatively quickly,
and people are regularly filling up
containers from one of the springs
associated with the latter aquifer.” He
suggests that it would also be useful
to conduct an audit of groundwater
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use in the greater Cape Town area,
“and to see how much more capacity
could be legally and sustainably
developed by individual landowners.”
He cautions, however, that even
if fully developed, groundwater
resources could only supply a
relatively small percentage of the
city’s water needs. Nevertheless,
there is potential to use non-potable
groundwater for industrial purposes
and domestic irrigation.
SRK associate partner and
principal hydrogeologist Desmond
Visser proposed the installation of
strategically placed boreholes or
wellfields in neighbourhoods where
the groundwater resource potential
is good, to supply irrigation water to
homeowners, parks, public buildings,
and sports fields.
Water Sewage & Effluent July/August 2017
“There are many areas in the city,
probably at least 70% of the Cape
Town area, where there is sufficient
groundwater for this to be feasible,”
says Visser. This system would
also aid in getting the city through
the dry summer months by reducing
the demand on potable water by a
considerable amount. “In the same
w ay, m any s chool s coul d hav e
boreholes to supply irrigation water
for sports fields and gardens,” he
says.
Some of these aspects have
already been implemented: SRK’s
Cape Town office is part of the
provincial Department of Transport
and Public Works programme to find
and develop groundwater sources for
new and upgraded schools. As part
of this programme, since 2011, over