Water, Sewage & Effluent January February 2019 | Page 21

fairly unknown method was selected,
due to the simplicity of the process
and anticipated savings on capital and
innovations
difficult to control within the required
limits. Investigation of alternative
technologies led to bio-filtration. This
Overstrand Local Municipality hosted a visit by the Department of Water and Sanitation
in July 2017. The visit was in keeping with the department’s study of various water
and sanitation projects that could offer countenance to the drought and subsequent
dwindling water shortages experienced in a number of public water supply schemes or
dams across the country.
tourism industry was not affected at all.
The only area affected was irrigation.
The use of boreholes comes with its
own challenges, such as water quality
and danger of over abstraction. A
comprehensive monitoring programme
of the boreholes has been established.
The monitoring protocol was developed
in consultation between Overstrand
Local Municipality, Fernkloof Nature
Reserve, CapeNature, Vogelgat Nature
Reserve, DWS, BGCMA, farmers, and
ratepayers. This programme includes
monitoring of the following: rainfall,
stream flows, water levels (surface and
groundwater), ecological conditions,
and water use and water quality. The
latter created a few obstacles.
Water
abstracted
from
the
Peninsula Aquifer is rich in iron and
manganese. (Iron 15 000–40 000μg/l;
manganese 1 000–2 000μg/l) (μ =
microgram; one μg = one millionth
of a gram and μg/l = microgram per
litre). The SANS 241 drinking water
standards specifies an iron content
of less than 300μg/l and manganese
less than 100μg/l. Overstrand initially
implemented chemical oxidation of
iron and manganese, which proved
Flash mixing chamber.
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