In a small remote town in the outback, a multi-million-dollar mega facility shipped in from America will soon turn potentially toxic drinking water into some of the cleanest in Australia.
It is the largest to be built so far and one of the first, but experts and activists say many more will be needed as Australia begins to deal with PFAS contamination.
A few years ago, residents of Katherine received the alarming news that the water they had been using was contaminated by a group of human-made chemicals known as PFAS, which some experts say are linked to cancers and other serious health concerns.
Between 1988 and 2004, during firefighting training at the Tindal RAAF Base, PFAS leached into the Katherine River and spread kilometres through the highly connected aquifer below.
The government advised against eating fish caught from the river, the local swimming pool was closed, bore-reliant properties surrounding the base were delivered bottled water by Defence and residents lined up for blood tests.
A major study on the health effects of PFAS and a landmark class action were launched and an interim water treatment plant was brought in, but its size left many in fear the clean water would run out.
Since then, residents have been clinging to the promise Australia's largest PFAS water treatment plant would be built and after years of delays it has been confirmed the facility will be completed by August at the latest.
Senior project manager at Power and Water Corporation Liam Early said it would deliver "very high-quality water," and agreed it would likely be the first of many needed across Australia as the nation began to grapple with the enormity of PFAS contamination.
"PFAS is a problem around Australia in a multitude of places," he said.
'The more we look, the more we're finding'
Associate professor Suzie Reichman, an expert in pollution science at the University of Melbourne, said the sticky substances were known as "forever chemicals" because of their persistence in the environment and could be found in hundreds of everyday products like cosmetics, sunscreens and non-stick pans.
"Evidence is mounting that high concentrations can have a number of health impacts, including cancer," Dr Reichman said.
"We haven't definitively proven that in humans, but we also don't know what concentrations cause [cancers].
"The Australian government has taken a very precautionary approach and we have very low thresholds for PFAS in the environment, including in drinking water.
"But because it wasn't on people's radars as a contaminant for so long, we're now seeing it has gotten out into the environment … the more we look the more we're finding."
With an already high reliance on groundwater projected to rise across Australia as surface resources become less available due to climate change and droughts, Dr Reichman said treatment plants, despite their expense, would offer a good solution.
"We have already contaminated the environment with PFAS, and if it's the only source of water, the solution to keep it safe for people and stock … is to clean it up," she said.
Issue unprecedented, Brockovich says
Erin Brockovich said filtration systems were being installed across the US, where PFAS had turned up in the water supplies of communities across the country.
"I'm currently working on this issue in Maine where we're looking at all of the organic farming being destroyed," she said.
"It's in the cattle, it's in the chicken eggs, it's in the aquifer, it's in people's [bore] wells.
"It's happening here in California, it's already happened to Alabama — it's happening everywhere in Michigan.
Ms Brockovich said a massive effort at local, state, and federal levels had begun to address PFAS including installing filtration systems on bore wells.
She said, after a slow start, the US was finally taking note of science and research that showed PFAS was widespread and dangerous.
She warned Australia needed to be prepared and proactive.
"We are seeing and making associations of this chemical with reproductive issues, in particular," Ms Brockovich said.
"We're seeing testicular cancers, we're seeing health implications with firemen and military men who are directly exposed to this chemical.
"So let's start being prepared, let's start looking at where the contamination is, let's start getting all the municipalities with filtration systems.
"We're not kidding when we say this is going to be the largest emerging groundwater contamination and food supply chain [issue] that we have ever seen.
How will Katherine's facility work?
The water treatment plant was delayed by a design process that took 24 months, as well as COVID and supply issues, Mr Early said.
When it is turned on it will be able to process 15 megalitres of water every day — more than enough for Katherine, which in the height of the dry season uses a maximum of 12 megalitres.
After water is sucked up from the groundwater through a bore, it is processed through the pressure vessels.
Microplastics made of resin called "media" capture the PFAS and remove it from the water.
"Then what we have is a back-flushing process," Mr Early said.
"The concentration [of toxic contaminants] gets flushed out and disposed of in an evaporation pond."
When enough solids had built up in the evaporation pond, Mr Early said, it would be dug out and "disposed of at a suitable waste disposal site".
While Defence continues to filter contaminated water and pump it back into aquifers at Katherine, Oakey and Williamtown, ongoing droughts and lingering health concerns are far from over for residents.
Peter Spafford, Katherine's sole GP during the peak of the PFAS scare, said long-term health issues were still a worry for residents despite a major study finding no conclusive evidence of increased risk of cancer or disease in the three towns.
Amid over-pumping, drought, and the steady influence of climate change, he said the treatment plant was a "bandaid measure".
"It's tapping into underground water supplies, which, certainly with decreased rainfall and the increased usage due to fracking, [are] not necessarily sustainable," Dr Spafford said.
