Lower Light (South Australia) – Chloral Hydrate
23/2/17 Lower Light Chloral Hydrate 146ug/L
Chloral hydrate is a disinfection by-product, arising from chlorination of water containing naturally occurring organic material (NOM). Chloral hydrate is a sedative and hypnotic drug. Long-term use of chloral hydrate is associated with a rapid development of tolerance to its effects and possible addiction as well as adverse effects including rashes, gastric
discomfort and severe renal, cardiac and hepatic failure.
2011 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.1mg/L
Lower Light (South Australia) – Trihalomethanes
Breaches to Australian Drinking Water Guidelines Levels Only
23/2/2017 Lower Light Wylie Road Trihalomethanes – Total 252 ug/L
Trihalomethanes Australian Guideline Level 250μg/L (0.25mg/L)
Why and how are THMs formed?
“When chlorine is added to water with organic material, such as algae, river weeds, and decaying leaves, THMs are formed. Residual chlorine molecules react with this harmless organic material to form a group of chlorinated chemical compounds, THMs. They are tasteless and odourless, but harmful and potentially toxic. The quantity of by-products formed is determined by several factors, such as the amount and type of organic material present in water, temperature, pH, chlorine dosage, contact time available for chlorine, and bromide concentration in the water. The organic matter in water mainly consists of a) humic substance, which is the organic portion of soil that remains after prolonged microbial decomposition formed by the decay of leaves, wood, and other vegetable matter; and b) fulvic acid, which is a water soluble substance of low molecular weight that is derived from humus”. Source: https://water.epa.gov/drink/contaminants/in
Lower Light (South Australia) – Chloroketones
23/2/17: Lower Light (South Australia): 1,1,1-trichloropropan-2-one 56.1ug/L
“GUIDELINE
Data are inadequate to set guideline values for chloroketones in drinking water.
GENERAL DESCRIPTION
The chloroketones are produced in drinking water as by-products of the reaction between naturally occurring organic matter and chlorine. No data are available on other sources or uses for these compounds. Concentrations of chloroketones in drinking water reported overseas are very low and are estimated at less than 0.01 mg/L.
TYPICAL VALUES IN AUSTRALIAN DRINKING WATER
In major Australian reticulated supplies 1,1,1-trichloropropanone has been recorded in concentrations up to 0.02 mg/L, but it is usually below the limit of determination of 0.0005 mg/L. No data are available for other chloroketones.
LIMITING FORMATION IN DRINKING WATER
The presence of chloroketones in drinking water can be minimised by removing naturally occurring organic matter from the source water, by reducing the amount of chlorine added, or by the use of alternative disinfectants.” 2011 ADWG
Lower Light – South Australia – Temperature
December 22 2016: Lower Light (South Australia) Wylie Rd – Temperature 22C
January 24 2017: Lower Light (South Australia) Wylie Rd – Temperature 22C
February 23 2017: Lower Light (South Australia) Wylie Rd – Temperature 22C
March 23 2017: Lower Light (South Australia) Wylie Rd – Temperature 24C
April 7 2017: Lower Light (South Australia) Wylie Rd – Temperature 21C
GUIDELINE
“No guideline is set due to the impracticality of controlling water temperature.
Drinking water temperatures above 20°C may result in an increase in the number of
complaints.
Temperature is primarily an aesthetic criterion for drinking water. Generally, cool water is more palatable than warm or cold water. In general, consumers will react to a change in water temperature. Complaints are most frequent when the temperature suddenly increases.
The turbidity and colour of filtered water may be indirectly affected by temperature, as low water temperatures tend to decrease the efficiency of water treatment processes by, for instance, affecting floc formation rates and sedimentation efficiency.
Chemical reaction rates increase with temperature, and this can lead to greater corrosion of pipes and fittings in closed systems. Scale formation in hard waters will also be greater at higher temperatures…
Water temperatures in major Australian reticulated supplies range from 10°C to 30°C. In some long, above-ground pipelines, water temperatures up to 45°C may be experienced…
The effectiveness of chlorine as a disinfectant is influenced by the temperature of the water being dosed. Generally higher temperatures result in more effective disinfection at a particular chlorine dose, but this may be counterbalanced by a more rapid loss of chlorine to the atmosphere (AWWA 1990).