Risk of a rare black water event not seen in the Katherine region for 15 years triggered officials to ship in about 300,000 litres of drinking water at the end of last year - luckily it was never needed.
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At the onset of the 2020 wet season, Power and Water officials convened in Katherine holding concerns the first flush of the season, washing built up debris into the river, would be followed by a period of dry, leaving too many solids in the water to treat.
Almost two weeks of no access to clean drinking water in the town 15 years ago was still fresh in everybody's mind.
Subsequent wet seasons without good rain and the prediction of La Nina conditions, only exacerbated the matter.
Visibly, the river still appears quite muddy, but Power and Water's Senior Manager of Service Delivery and Water Services, Eric Boyle says the risk to the river water supply has now passed.
Peaking at 9.94m on December 31 2020, to date this is the highest the river level has been since the 2017/18 wet season, Mr Boyle said.
It also meant the turbidity in the water didn't get high enough for long enough to threaten water security in Katherine, he said.
"Previously, we could draw water from the bore, and it wouldn't have been too much of an issue, but because the bore is contaminated with PFAS we couldn't use that source as a back up," Mr Boyle said.
A number of options were investigated as debris from the catchment built up.
"We had to find an alternative source - that is the position we were in," Mr Boyle said.
"We purchased three days worth of drinking water for Katherine residents, we looked at tanking in water from Darwin and we approached [the Royal Australian Air Force] to ask if we could use one of their two PFAS treatment plants."
In the end the team used two filters, which remove PFAS from water, from Katherine's incoming treatment plant, expected to be completed by the end of this year, and connected them to old bores, Mr Boyle said.
"We had an alternative supply, but we are now in a position where we have good flow to treat the water normally."
"Thanks to all the rain," he says, "water demand in Katherine has reduced significantly, which means there has been plenty of treated water stored in the tanks to ensure continuity of supply to Katherine."
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