Ground-breaking APS project enables Purple House to reuse reverse osmosis brine water


Western Desert Nganampa Walytja Palyantjaku Tjutaku Aboriginal Corporation, fondly known as Purple House, was set up with independent community funds from an auction of works by Papunya Tula Western Desert artists in November 2000 at the Art Gallery of New South Wales. The fundraiser was a response to a crisis in Central Australia’s Pintupi communities, as a growing number of elders were forced off Country and away from family for dialysis in Alice Springs. Disconnected from Country and community, patients suffered great loneliness, reduced health outcomes and the strength of culture and families was compromised. So, the community decided to do something about it. Founded and run by the community, Purple House delivers a unique model of care based on getting people home to Country, supporting them to live a good life and working the right way both culturally and clinically. This has enabled elders to remain connected to community and Country; maintain leadership roles; and transfer cultural knowledge and practices to the younger generations. Purple House now has a permanent dialysis unit in 18 remote communities across the NT, WA and SA, and runs a mobile dialysis unit called the Purple Truck, with a second truck launching in 2021.  

Each dialysis treatment uses approximately 400 litres of town water, which means each site disposes tens of thousands of litres of ‘medical wastewater’ every week. In addition, many of the 18 remote sites where Purple House operates are at high, very high or extreme risk for water security. With the intention to continue expanding to new regions and communities, Purple House approached Jawun expressing concerns about water security and future water use and asked for a secondee to help explore opportunities for ‘medical wastewater’ reuse, and to prepare future Purple House clinics to be greener. 

Ms Mio Kuhnen was invited to take a secondment from her APS Department of Agriculture, Water & the Environment role and join the project. Mio possesses a thorough understanding of Central Australian geography, having previously spent time in the remote community of Yuendumu.   


Mio is a geologist who specialises in soil sediment particulates that enter lakes, and possesses the unique skills needed to understand the mineral composition of Purple House’s medical wastewater. Mio was paired with Purple House biomedical engineer, Dr Michael Smith.  Michael’s role is to ensure Purple House’s water and dialysis equipment operates correctly throughout its lifecycle.  Michael is also involved in the design of water treatment systems for new sites and is interested in developing water-efficient dialysis services. 

Mio analysed existing and future potential Purple House dialysis sites, water uses, quantities, supply systems, and greywater handling constraints. Feedback from both Michael and Purple House CEO Sarah Brown AM noted frequent implementation roadblocks when it came to options for alternative water sources and reuse.  Consideration also needed to be given to whether each water supply would meet each remote community’s demands, alongside human resourcing and management.  

Working collaboratively with Michael, Mio set about researching the medical wastewater legislation in the states and territories in which Purple House operates. During the secondment, Michael attempted to troubleshoot alternative options to tackle elevated fluoride levels in remote Kiwirrkurra town water – an issue that prevents successful dialysis on country. Mio’s research uncovered strict approaches to water reuse, particularly in South Australia, and through Purple House connections, he reached out to discuss the issue with Australia’s leading dialysis expert in Melbourne, Professor John Agar.  Dr Agar was well known for his work on reusing reverse osmosis brine water in hospitals, specifically for watering sports fields during droughts. Dr Agar was apprehensive that Mio could successfully approach this issue simply in conversation with individual states, saying “if you can pull this off, that’d be pretty impressive”.  

Mio and Michael were working hard on finding a solution, and inspired by an Indigenous guest speaker, Jenni Nixon, who spoke to the secondees about her childhood growing up in a Town Camp and the role sport played in offering her a good future, Mio approached the South Australian government in an attempt to have their health systems and water legislation assessed. 


Mio presented the South Australian Department of Health with a fabulous, multiple-outcome idea: if the majority of the dialysis water could be reused to offset the town water consumption of Purple House clinics (for washing machines and toilets), the remainder could be offered to regional Land Councils to top up swimming pools and water sports grounds. The additional benefit to dialysis operations was reduced town water consumption and increased recreational and sporting opportunities, leading to better mental health, which Mio better understood after hearing from Jenni Nixon.  

On the second-last day of her secondment, Mio received a response from the South Australian Department of Health. Having completed a risk assessment and analysis, they were very comfortable for Purple House to reuse the reverse-osmosis brine water. Mio said that: 

 “This outcome will assist future Purple House buildings; the reverse osmosis brine can now be used in SA to create greener practice. In some locations, this could allow for developments where it is currently not possible due to water restrictions.”  

This was a more successful outcome than anyone had expected, Mio included. Purple House wouldn’t have to wait for legislation to be amended, they had simply been granted an exemption and could immediately start undertaking the various steps towards implementing water reuse in all Purple House sites located in South Australia.  

Michael noted: 

Mio’s unique skillset allowed her to successfully communicate with bureaucrats and government agencies. Her greatest achievement was to get the government to put this in writingThe impact of her secondment is that effective immediately, Purple House can reuse the reverse osmosis brine water for any suitable purpose, rather than discarding it to waste. This means we can advise the architects responsible for designing the new Coober Pedy dialysis unit to incorporate the necessary plumbing technicalities into their architectural plans.” 

Next Steps 

Jawun secondments often require perseverance, and Mio has continued negotiating with the Western Australian and Northern Territory Governments. Three weeks after her secondment, Purple House also received approval from WA to reuse the reverse osmosis brine water. Mio said, “this is so exciting as it’s meant a domino effect is happening whereby Purple House can start retrofitting some of the buildings and reuse that water. I just couldn’t believe it all fell into place! This secondment with Jawun really transformed me. It changed my outlook on life and I felt like I was able to achieve something ground-breaking by utilising a skill I had never previously identified – my ‘bureaucratic intelligence’, as Michael would say.”