Casino residents may have noticed their water is a little brownish recently, but authorities have advised it is still safe to drink.
Richmond Valley Council staff say the discolouration is due to abnormal elevated levels of the naturally occurring element manganese in Casinos water storage caused by recent heavy rain run off.
Council general manager Brian Wilkinson said manganese may also give an undesirable taste and odour to water but while the water may look slightly brown, it was safe to drink, with levels of manganese well within the Australian Drinking Water Guidelines.
Though no additional treatment of household water was required, Mr Wilkinson said the discolouration may cause staining when washing clothes and recommended using cold water, avoiding bleaching agents or the use of the spin cycle.
He said Council was trying to find suitable washing products that would not be affected by manganese and would advise residents in due course.
Mr Wilkinson said the problem was out of Councils control and the discolouration may continue for some time until the river was flushed by rain.
Councils director of works Gary Murphy said staff were unable to determine the cause of the elevated manganese levels and were working hard to fix the problem.
Mr Murphy said the water above the Jabour Weir, which supplies the town, was very dirty and appeared to have a high organic load.
Weve tested the water in the weir and found elevated manganese levels but where it comes from we dont know, he said.
He said manganese, which existed naturally in water, could also have originated from fertilisers used in large-scale cropping which, when heavy rain fell, could run off into the weir and cause elevated levels, but its hard to determine.
Unless we find a way to process the manganese out of the water ... the problem will be around for some time until the river is flushed by rain, he said.
One of the biggest problems caused by the discolouration is the staining of white clothes or materials during washing.
Weve had some pretty irate young mums complaining about stained nappies, Mr Murphy said.
Council is currently trialling the use of compounds such as citric acid in laundromat tests to see if it can counter the staining from the manganese and will soon be recommending to residents what they can use.
Casino Ratepayers and Residents Association member Pam Brayley said residents had noticed the discoloured water last Friday and notified Council.
The waters perfectly all right but the biggest problem is the stained washing and Council is doing its best to fix it, Mrs Brayley sad.
Mrs Brayley said some local motel and laundry operators appeared to have been hardest hit with so much white linen.
Its one of those rare, unfortunate things that happen ... but not as bad as some places out west where you can see the sediment thats settled in the water, she said.
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