P OW E R A N D WATER CORPORATION
Power and Water Corporation has to meet water quality
requirements set by the Northern Territory Department of
Health based on expert recommendations.
This fact sheet is to tell you
more about your water supply,
its water quality and how we
look after it.
Your
water
supply
Ali Curung’s water
comes from groundwater.
Two bores pump
groundwater
up from below
the ground to a
storage tank.
Water is kept clean
by adding chlorine.
Your ESO checks the
level of chlorine in
the water every day.
Groundwater is stored under
the ground in rocks, or between
sand, silt, clay and gravel, which
adds minerals to the water.
How do we look after your water supply?
Your water supply is automatically cleaned with
chlorine to prevent bugs that are too small to see
and make you sick. These bugs may be in the
groundwater or tank and pipes.
• The water supply is checked each month:
- to make sure there are no bugs in the water
- to see that the system is being maintained properly.
• The water supply is checked 3 times a year:
- to keep an eye on the levels of elements and minerals.
These samples are sent away and tested for quality.
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Water quality: what is it?
Water quality is measured by looking at what is in water
and comparing it against certain guidelines. The Australian
Drinking Water Guidelines (ADWG) are used to provide
targets for providing an acceptable water supply and the
ways to meet them. The water quality targets come from the
results of studies, combined with safety margins.
ADWG:
Australian
Drinking Water
Guidelines
Microbiological (bugs too small to see)
Microbiological characteristics in the water are caused by people,
animals and insects near the water supply. They are living bugs
(micro organisms) in the water. Chlorine kills these bugs so they
can’t harm you.
One bug that is monitored to show if faeces (poo) has
polluted the water supply is Escherichia coli, or E. coli.
Water supplies are protected from bugs by making sure:
equipment
is in good
condition
+
fences are
used to keep
animals out
+
human settlements
do not pollute the
water source.
Chlorine is also added to provide protection when the water travels through pipes
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Physical and chemical
(looks, taste, smell)
Radiological
(can’t be seen, tasted or smelt)
Physical and chemical characteristics
depend on the minerals that are
dissolved or floating in the water
from rocks, sand, silt and clay. Often
these are determined by the type of
water source. In groundwater there
are many minerals in the soil and
rock that are dissolved by the water
over time. These can affect the
water’s taste, smell or health effects.
Chlorine added to the water to keep
it clean can also make the water
taste different.
Radiological characteristics depend
on minerals in water that give off
radiation. The radiation is like radio
waves – you cannot see it. Radiation
also comes from things like mobile
phones, microwave ovens and TVs.
Radioactive minerals in water can be
natural and come from local rocks
underground or be caused by mining
and manufacturing. At high levels,
radiation from water can be harmful
to people who drink it.
Of the 29 water quality targets,
Ali Curung’s water has 5 of these
characteristics that exceed the ADWG,
which are described in the next section.
Ali Curung’s water is below the ADWG
for radioactivity.
What elements and minerals are in Ali Curung’s water?
Ali Curung’s water
is below 24 of the
29 water quality
targets that are
regularly tested.
The water supply in Ali
Curung is regulated by
the Northern Territory
Department of Health for
drinking water quality.
Checked for aesthetics
(look, taste and smell).
Nitrate
Checked for health
reasons.
Health guideline
Ali Curung
Darwin
3 mg/L
Alice Springs Ampilatwatja
8 mg/L
26 mg/L
Good
Above
guideline
79 mg/L
50 mg/L
Guideline
(ADWG)
Fluoride, nitrate,
sodium, hardness and
total dissolved solids are
at higher levels than the
targets recommended
by the ADWG.
Darwin
2.1 mg/L
Alice Springs Ampilatwatja
1.1 mg/L
Children under 3 months
of age should not be given
water above guidline
values. Formula should
be made with bottled
water. Adults should not
drink water higher than
100mg/L in nitrate.
Fluoride is present in
toothpaste and is often
added to water supplies
to prevent tooth decay.
Too much fluoride can
cause weak teeth and
bones, particularly in
young children.
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What elements and minerals are in Ali Curung’s water?...cont
Iron
Darwin
0.024 mg/L
0.12 mg/L
Ali Curung
Darwin
Alice Springs Ampilatwatja
0.05 mg/L
0.03 mg/L
0.3 mg/L
Guideline
(ADWG)
Iron is required for human
health and it is common
in groundwater. Too much
iron in water can change the
colour to orange/brown,
cause build-up in pipes
and make the water taste
metallic and smell bad.
Sodium
3 mg/L
Alice Springs Ampilatwatja
76 mg/L
120 mg/L
180 mg/L
Guideline
(ADWG)
Good
Above
guideline
207 mg/L
Darwin
Alice Springs Ampilatwatja
492 mg/L
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Sodium is a major part of
table salt. It is found in
many foods but should be
limited. When there is too
much sodium in drinking
water it may taste salty
and unpleasant.
‘Hard water’ contains
lots of magnesium and
calcium so scale can build
up on hot water heaters,
kettles and appliances.
In hard water soap won’t
lather as much.
What elements and minerals are in Ali Curung’s water?...cont
Total dissolved solids
Ali Curung
Alice Springs
Ampilatwatja
58 mg/L
452 mg/L
993 mg/L
Darwin
Alice Springs
Ampilatwatja
500 mg/L
Guideline
(ADWG)
Good
Above
guideline
957 mg/L
Darwin
0.2 NTU
The total dissolved solids
(TDS) is a measure of the
minerals and organic
matter in the water, and
the taste is salty. It shows
how much ‘stuff’ is in the
water, but not whether it
is good or bad.
Turbidity measures how
cloudy water is. The
lower the number for
turbidity, the clearer
the water is. Turbidity is
caused by small particles
floating in the water.
Summary
• Power and Water Corporation has the responsibility for providing safe drinking
water to Territory Growth Towns and communities.
• We regularly report the results of water quality tests to the Department of Health.
• The Northern Territory Department of Health regulates Ali Curung’s water supply
for drinking water quality.
• Power and Water Corporation is installing an advanced water treatment system in
Ali Curung to improve water quality.
• Further information:
For water quality enquiries 1800 245 092
For detailed information on all measurements taken for Ali Curung’s
water, please see the latest Water Quality Report online at:
www.powerwater.com.au/newsroom/publications
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