Lead and chlorate recorded in drinking water
MACKAY failed to meet safe drinking standards five times in a month, with tests recording lead and persistently high levels of chlorate in the water.
The failed water tests at Nebo and Bloomsbury were revealed in a Mackay Regional Council Water Services Monthly Review.
The report said lead was found in water taken from the Nebo Road Water Treatment Plant, while high levels of chlorate were recorded in Bloomsbury four times in July.
The report said four water samples taken from the Bloomsbury Water Supply Scheme had more than 800 micrograms per litre of chlorate.
It said the contaminant was caused by the plant using sodium hypochlorite, or liquid chlorine, to remove iron and manganese and to disinfect the water.
Director of Engineering and Commercial Infrastructure Jason Devitt said the council was aware of the high chlorate levels at the Bloomsbury Water Treatment Plant and the plant was being upgraded to address the issue.
"Chlorates are considered an emerging contaminant," Mr Devitt said.
"There is no suggestion that the high chlorate levels at Bloomsbury pose a short or long-term health impact to our customers."
Mr Devitt said the council was working with Queensland Health and the drinking water regulator to address the Bloomsbury water issues.
He said the lead readings from the Nebo plant were likely caused by dust contaminating the water sample.
"Investigations were carried out at the Nebo Road Water Treatment Plant and the regulator
found no high-level concentrations of lead at the plant and believes the sample was
contaminated by dust," he said.
Mr Devitt said lead had not been detected in any further tests, and the incident was closed by the Drinking Water Regulator.
He said the non-compliant incidents were minor, but the council would take the failed tests seriously.
The council did not answer whether residents were told of the failed tests, or how many customers may have been exposed to the water.
Mr Devitt said of the 129 water samples collected in July only five returned failed results.
He said the council performed more than 300,000 tests on Mackay's drinking water each year to ensure it was compliant with Queensland Health and the Australian Drinking Water Guidelines, as well as the National Association of Testing Authority.
It was not the first time water issues had impacted the council's drinking water. Eton residents were forced to buy bottled water because of elevated selenium and uranium levels in town water bores in 2018.
Mr Devitt said the water from Mackay Regional Council had consistently produced award-winning drinking water.
He said in 2018 water from the Nebo Road Water Treatment Plant was named Queensland's Best Tasting Tap Water, the Marian Water Treatment Plant was named Australia's Best Tasting Tap Water in 2019 and second-best in the world in 2020.
CORRECTION: An earlier version of this story had a photograph of Isaac Regional Council water and wastewater operators Marie Jones and Anthony Waller at the Nebo Water Treatment Plant project. That water plant is in Nebo and not associated with the Nebo Road plant in Mackay that returned five failed results. The Daily Mercury apologises for the error.