Cross section of a typical aquifer. Groundwater exists in two environments: confined and unconfined.
innovations
“Now, if we are looking long term
and we decide this is an important
resource to utilise despite the
potential impacts then, that’s fine —
we can then follow due environmental
process in doing so to mitigate that
impact.”
Limberg concurs that the City’s
augmentation schemes do not directly
address Day Zero this year, but rather
target the summer of 2019. Despite
repeated requests for confirmation of
the numbers and specific locations
of prospective drill sites in the TMG
Aquifer, the City of Cape Town failed to
provide the information by the time of
publication. u
About the author
Aletta Harrison is a multimedia journalist with a passion for environmental
stories. Her work has appeared on various platforms on air and online,
including News24, Eyewitness News, TimesLIVE, Chronicle, CheckPoint –
eNCA, GroundUp, Anadolu Agency, and Moneyweb. Clients also include
UNICEF, TRT World, and Health-e News. Currently she is working at News24
where she heads up multimedia projects
Water Sewage & Effluent March/April 2018
31
“International examples of where
aquifer abstraction has gone horribly
wrong include the unconfined Swan
plain aquifer, near Perth, Australia,
where pumping is now severely
regulated to allow for an adequate
ecological supply. This follows
extensive die-back of Australian
proteas (Banksia species) directly
attributed to drawdown of the water
table as a result of abstraction.”
West says while environmental
scientists recognise that the City
is in a crisis, risks of forging ahead
without detailed and thorough
assessments are not merited,
considering the relatively low
yields and the fact that the TMG
groundwater is only expected to
come online in May, therefore having
no real impact on Day Zero this year.
“If it does have an impact on
dropping water tables, or causing
collapses or reductions in flow, that
might really manifest itself in a much
longer timescale than we can detect
in the short term,” West says.