Water Recycling comes with a Health Warning
01/06/2011 12:03 Category: Industry News
Article by Paul Murray in 'The West Australian'
As Colin Barnett found out during the 2005 election campaign, the politics of water in WA can be devastating. A canal to bring the staple of life from the north to Perth seemed like a no-brainer. It wasn't. His Government's new plan to fast-track the trial on recharging Perth's overstressed underground aquifer with treated wastewater is similarly attractive at first blush. We need to get past that point quickly and look at the real issues. The recycling project is both environmentally attractive and just one of a patchwork of programs that will make Perth's water supplies more sustainable. But its environmental attractiveness is challenged by the health implications. And its place in the patchwork is relative to a number of other alternative potential sources - all mitigated by the health risks. A month ago, Water Minister Bill Marmion reported that the first three months of trials putting treated wastewater into the Gnangara mound at Beenyup had been successful, with "all water samples meeting health and environmental guidelines". But we don't know what those guidelines are. While stressing the trials had two years to go, Mr Marmion noted that "if successful, groundwater replenishment could provide a new major water source option". However, during the trial, about 3.4 billion litres of water is being added to groundwater supplies. So an element of Russian roulette is already under way. "While we are confident that technically this trial will prove groundwater replenishment is a viable option for the future, it is crucial we have the support of the community," Mr Marmion said back on April 13. Skip ahead a month, and past some very dire predictions that our dams supplying metropolitan drinking water will be expended by the end of next summer, and Mr Marmion has asked his bureaucrats to push the trial forward. He wants the recycled water source available within 18 months. The rush is obvious. But it's a rush past the obvious availability of a massive water resource in the southern Yarragadee aquifer, the possibility of expanding the Binningup desalination plant - and any commitment to drawing from the State's northern potential, to which the Premier says he remains attracted. It is impossible to separate water from economic activity. One of the attractions of bringing water from the north is that it opens up economic opportunities along the route. One of the attractions of the southern Yarragadee - as the University of WA's Professor Jorg Imberger repeats incessantly - is that it can be harnessed quickly and at relatively low cost, while monitoring its environmental effects. However, Mr Marmion seems to be favouring the Beenyup option and admits he would like to be ready to push the button on it next year. But what about the community support he says is essential in the newly-compressed timeline? Last week on radio I asked him about any gauging of public support. He dodged the question, so I pursued the Water Corporation this week about when it had last surveyed the issue. It has monitored public acceptance since 2007 through an annual random telephone survey, the next due next month. As we all know, the results of these surveys depend almost entirely on the questions that are asked. Apparently, last year's survey on "community attitudes to groundwater replenishment" showed only 6 per cent opposition. I presume the question asked didn't get anywhere near: "Would you be happy drinking your neighbour's recycled urine?" After all, everyone agrees with "groundwater replenishment". However, the corporation did admit that 42 per cent of people said they needed more information before they made a decision. And this is the salient point. Apart from public hesitation, there is substantial scientific opinion against this process. One of Australia's leading infectious disease experts, Professor Peter Collignon, says mass production of recycled water can be made safe for human consumption - but probably not 100 per cent of the time. And it's those glitches - those unsafe times - that could pollute an aquifer. "If you want to take sewage and make it safe you need the same processes as a desalination plant - and then some," he said. "Viruses are very small and if you want to get rid of all those drugs and bugs from the water - and sewage is one of the most contaminated sources of water you can find - you have to put it through membranes under pressure." But those membranes are very fallible. In most places where it had been tested, viruses got through. To ensure a system was safe, it needed continuous real-time testing for viruses and pathogens, which was expensive. Professor Collignon said it was important that any treated wastewater injected into an aquifer was not redrawn within 12 months, during which time natural processes helped purify it. This is a public debate that needs to be won. The Barnett Government has become fat and lazy about these issues. It doesn't need this one turning into another Colin's Canal through sheer indolence. The peasants might not be revolting at present. That doesn't mean they won't become revolting in the future.