LiquID Case Study 1: Real-time water quality monitoring, of a Queensland river,
using a ZAPS LiquID Station.
Queensland has many coastal rivers that rise on the eastern slopes of the Great Dividing
Range and flow eastwards to the sea. Several of these are the sources of drinking water for
large and small communities, both on the coast and inland.
Queensland River Basins (http://www.bom.gov.au/qld/flood/brochures/river_maps.shtml)
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The North Queensland climate is characterised by two distinct seasons, with warm
temperatures and a low rainfall during the winter period while summer sees higher rainfall
and warmer, balmy temperatures.
Rainfall during the summer months is high, and there can be several very significant rainfall
events each year.
North Queensland Average Rainfall (https://www.travelonline.com/tropical-northqueensland/weather.html)
During these rain events, very high flows occur. Run-off carries high concentrations of
suspended particulate and organic matter, nutrients, sulfate, E.coli and and some heavy
metals. Water quality shifts can be dramatic and transient or extended. The impacts on
water treatment plants can be significant, and without the knowledge of what is coming, the
ability of water treatment plant managers to make effective operational decisions is severely
hampered.
On the other hand, real-time knowledge of coming changes in water quality, allows
operational staff to adjust coagulant dose, vary filter operating parameters, increase
disinfection dosing – or even shut the plant down.
The ZAPS LiquID Station is an ideal real-time multi-parameter water quality monitoring
device for use in river monitoring. It is unrivalled in its performance as an early warning and
event detection tool, optically monitoring parameters including TOC, TSS, Turbidity, Colour,
Nitrates, Dissolved Iron, E.coli, Chlorophylls and Phycocyanin. It can be easily integrated
with non-optical monitoring devices to provide further information such as Dissolved
Oxygen, pH, Conductivity and River Height. The LiquID Station is fully automated, including
self cleaning and calibrating functions. It provides email alerts and can also be integrated
with auto-samplers, allowing the possibility of remote triggering of the auto-sampling
function by changes in monitored water quality.
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The following trend graph shows data from a LiquID Station, installed several kilometers
upstream of a drinking water treatment plant in North Queensland. The correlation
between rainfall events, during the summer of 2016-17, and shifts in TOC and E.coli levels is
obvious and dramatic. Advance warning, of what is on the way, is provided to the water
treatment plant operators, helping them to better manage the plant operations and to
continue providing safe drinking water to their customers.
Trend data from the LiquID Station, showing significant shifts in TOC and E.coli during rain
events over the summer of 2016-2017.
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