A new wastewater treatment plant soon to be installed at one of Australia’s Antarctic bases will enable the 12-year-old practice of pumping poo and other waste into the ocean to finally come to an end.
The $1.5 million “state-of-the-art” technology will “use germ-zapping technologies to process human and kitchen waste into drinkable-quality water that will have minimal impact on the marine environment when it’s discharged into the ocean”, the Australian Antarctic Division (AAD) said.
In 2005, equipment at Davis, 4800 kilometres south-west of Hobart, failed. Since then, effluent has been discharged to the ocean from a pipe at the water’s edge near the station’s wharf.
While that disposal method met environmental protocols, an environmental impact assessment revealed the effluent was “poorly dispersed” during the three-month period of the study, resulting in an “accumulation of faecal contaminants, heavy metals and persistent organic pollutants … and the exposure of seals and penguins to high levels of faecal bacteria”.
“Low levels of human-derived faecal contaminants were detected in sediments up to two kilometres in the direction of the main current flow,” AAD said in 2016.
“Sewage markers were also detected in two predatory sea-floor animals — a snail and fish — suggesting that some contaminants were entering the marine food chain.”
Michael Packer, the project engineer with AAD, said the process involved wastewater undergoing a series of “physical and chemical processes to produce the purest water possible”.
“The contaminated water, which is first treated by a secondary wastewater treatment plant, will undergo ozone and ultraviolet disinfection, ultrafiltration, chlorination and pass through a biological activated carbon filter and reverse osmosis,” Mr Packer said.
“The end product will be water that exceeds the Australian and World Health Organisation drinking water guidelines.”
‘Beautiful snow’ preferred option for drinking water
While there were “no current plans to use the purified water” for human consumption, the new technology would “ensure the water we discharge into the marine environment has a negligible impact”, Dr Rob Wooding, AAD’s general manager of support and operations, said.
“We have beautiful snow down there that we can make very high-quality drinking water out of,” Dr Wooding said.
“However, over time, we will need water for washing and other purposes.”
The new wastewater treatment technology has been trialled at TasWater’s Selfs Point site in Hobart over the past two years and will travel to Davis research station on the icebreaker Aurora Australis this summer, with commissioning scheduled for late 2018.
More plants will be built at Australia’s other Antarctic stations “in the future”, AAD said.