Let’s face it, we all feel a little bit icky when we think about toilet water generally.
If we are asked to think about transforming wastewater into drinking water, our stomachs are likely to respond with an indignant flip of protest. As much as the brain may try to reason, our natural impulses are stubborn, so while there is a weight of evidence and assurances that modern treatment technologies can create perfectly safe and pure water, there is an unavoidable psychological aversion to drinking water which has already been ‘used.’
However, we need to start coming to terms with alternative drinking water supplies as a very real opportunity to create efficient and sustainable water supplies for our cities.
The truth hurts
The truth of the matter is, we all drink ‘pre-loved’ water all the time. Water cannot be created, it is just constantly reinvented through the natural water cycle. Often, the recycling of water is even more direct in urban water systems, as wastewater discharged from one town merrily cascades down-river to the water supply of another.
In 2002, the City of Auckland added a much needed water supply from the Waikato River, extracting downstream of its competitive neighbouring city, Hamilton, whose residents gleefully joked “Flush twice please, Auckland needs the water.”
Australian cities and towns are no different – often settled near a major river, urban areas utilise the same waterways for water supply and discharge of treated wastewater and urban stormwater. Even when water supplies are solely from rural catchments, we are fooling ourselves to think that the cattle that populate our bucolic vision of the countryside haven’t done their business anywhere near the local stream. Somehow we all manage to turn a blind eye and put these ‘catchment scale’ water recycling systems in the acceptable box to avoid triggering an unwelcome stomach spasm.
So why is the use of recycled water for drinking water so hard to swallow?
Perhaps we have been brainwashed by too many mineral water adverts claiming that water has been mined from far away glaciers, dosed with the freshness of a spring day and blessed by pixies before it is bottled for our enjoyment, all the while giving us a false and hugely impractical expectation of how our water should be sourced. The clever spoof "Last Call at the Oasis" starring Jack Black, suggests we could all be enthused to taste ‘Porcelain Springs’ if the advertising was right:
New drinking water sources: the next frontier
The urban water supply challenges facing Australian cities are very real and urgent. Traditional surface water and groundwater supplies are strained and set to dwindle with the effects of climate change. More and more, cities are looking to desalinate seawater to secure water supply, with Melbourne recently placing its first order from the controversial Wonthaggi Desalination Plant in preparation for next summer. Desalination is not only far from our pixie-kissed impression of what a water supply should be, but is also highly energy intensive and adds a significant hike to the customer’s water bill.
On the other hand, recycled water could be smarter and more sustainable alternative to supplement drinking water supplies in cities, having several distinct advantages:
- secure supply: treated wastewater can be recycled again and again
- established collection and treatment assets: wastewater is managed locally and treated to a standard suitable to be released to the environment, so the collection and treatment systems are already in place, ready for ‘top-up’ treatment to be added to recycle the water to drinking standard
- broader environmental benefits: much like waste, the reuse of local water helps to ‘close the loop’ and reduce pollution to the environment and reduce carbon associated with moving water around
The technology to utilise recycled water for safe drinking water exists, and feasibility has already been proven elsewhere. Parts of California already utilise treated wastewater as part of their drinking water supply, and plans are now afoot to expand schemes in the wake of the drought crisis. Similarly, Singapore has utilised alternative supplies for drinking water for the last 15 years.
What’s needed is a shift in social and political acceptance, and there’s nothing like a crisis to do that. Faced with the impacts of drought, we have seen public perspectives on water management change substantially in the past, and it’s likely they will again. Following the Millennium drought in Australia it has become increasingly common to recycle wastewater for non-potable supplies (not for drinking) such as irrigation and toilet flushing. However, the cost of duplicating plumbing and supply systems often makes these schemes commercially unattractive. If we are courageous enough to begin utilising recycled water as part of the water supply, the business case, if not the concept, is much more palatable.
If we just can’t get our head around a toilet being part of the water supply equation, there are other alternative drinking water sources to consider, such as harvested urban stormwater, which our cities produce in bulk and subsequently damage our waterways and bays. City of Orange in New South Wales supplements its water supply with harvested stormwater which is captured and transferred to its main supply dam to be mixed with freshwater reserves before treatment. Then there is roof water, which people have been drinking for centuries but has been gradually phased out in favour of centrally controlled supplies.
I could keep listing examples, but we all know that recital of facts will only go so far – acceptance needs to be drawn out of a much deeper community conversation about how we will meet our water challenges. It may take the next drought crisis to trigger a taste for alternative drinking supplies in Australia, but it’s important to start having the conversation now to plan solutions that make good sense.