Smarter urban water
in Environment on 31 July 2014
After the drought, there's a quiet revolution in the pipelines.
TWO blue glass boxes rise from the grass next to the Melbourne Cricket Ground. If you glance at them – on your way to an Aussie Rules game, of course – you’ll notice some pipes inside.
Nothing special, really. Only a sewer mine.
Or, as the officials prefer: the Yarra Park Water Recycling Facility.
Below ground, a large pipe snakes uphill, avoiding tree roots. It taps into the main vein below the snooty suburb of East Melbourne, and sneaks off with its shit.
In summer, the large parklands around the ground are irrigated entirely with recycled water. In the winter, it flushes the loos of tens of thousands of spectators each weekend.
The facility supplies cheaper water than the gigantic Victorian Desalination Plant, which was built with considerable cost and controversy one hundred kilometres south-east of the city. Both were completed in 2012. But the desalination plant, unlike the sewer mine, has never produced a drop.
The Yarra Park Water Recycling Facility. Photo by ARUP
Something strange and remarkable has happened in Melbourne. Five years ago, the city of over 4 million inhabitants nearly ran out of water. Now it is regarded among the most innovative, water-smart cities in the world.
From 1997 to 2009 southern Australia suffered through the “millennium drought”, its longest dry spell on record. “The drought was a huge wake-up call,” says Dr Cathy Wilkinson, an executive director at the Office for Living Victoria, the government body now in charge of water policy. “The way water was managed had a huge impact on people everyday. Waterways were drying up, junior sports clubs couldn’t play on their ovals because they were too dry and dangerous.”
The government issued tight water restrictions. Newspapers reported on neighbourhood water vigilantes; people using rainwater tanks feared being seen with green lawns. Water consumption dropped 40 per cent, per person per day. Without that shift, drinking water supplies would have run out.
In panic, the then Labor government ordered a mammoth desalination plant – with a top capacity of half the city’s water consumption – and a pipeline to bring water from the north of the state.
The imminent threat concentrated minds elsewhere. Local councils, unable to water outdoor space, began to seek alternatives.
Professor Ana Deletic, associate dean of engineering at Monash University, explains that research flourished, especially into reclaiming stormwater – the polluted rainfall that flows off roads and car parks, into the bay.
“The same amount of runoff goes into Port Phillip Bay as we use in Melbourne each year,” she says. “We were talking about how we could capture some of that water and reuse it, but also save our streams in the process.”
The university now hosts the Cooperative Research Centre for Water Sensitive Cities, which has over 70 researchers and a budget of over $100 million. It’s a multi-disciplinary body, with programs looking at social drivers, planning, technology and, importantly, how to get it all adopted in real life.
Professor Deletic’s speciality is green walls that treat greywater. “It’s a technology that cools your city, makes it beautiful but also produces water,” she says.
Enter a conservative state government in 2010. It mothballed the desalination plant and the pipeline and established the Office of Living Victoria, with an holistic mandate – much like what the academics had ordered.
Dr Wilkinson says that, historically, water planners sought to predict and provide. The city was a drain; waterways just pipes to the bay.
Now the vision is decentralisation. Catch and store water where it falls. Treat stormwater and wastewater locally, where possible, and reuse it to irrigate parks and gardens. Use drinking water for drinking, not for everything.
“When we do our long-term water planning, we need to think about the complete range of sources, and match the right water for the right job,” Wilkinson says. “At its heart it’s about how Victoria can be resilient and liveable in the face of a whole heap of changes that are going to happen.”
Chief among these changes are a fast growing population – up to 7 million by mid-century – and a harsher climate. Droughts are projected to become more frequent and severe. Rainfall is likely to decrease, but when it does rain, it’s more likely to pour. The millennium drought was followed by two dangerously wet years, including the wettest summer on record, which flooded a third of the state.
The government has begun funding suitable projects and “whole-of-water-cycle” management plans are being drawn up across the city.
The office’s modelling anticipates an astonishing range of gains by 2050: nearly halving mains demand, cutting one-third from wastewater volumes, reducing stormwater runoff by 40 per cent, and saving one-third of the electricity used in the system. All at a tidy saving of up to AUD$7 billion.
What makes this all the more peculiar is that otherwise, the government has been environmentally backward. This March, the state’s commissioner for environmental sustainability quit early, claiming the government was advising bureaucrats not to use the term “climate change”. The Office of Living Victoria has been the subject of controversy too. An investigation by the Ombudsman into its procurement practices is expected within weeks. There are also rumblings about a lack of transparency in its modelling.
Michael O’Neill, senior environmental consultant at ARUP, was part of the team for the MCG sewer mine. He says Melbourne’s approach is internationally renowned, “not just in academic and policy circles, but also in the multinational engineering firms”.
The Yarra River, which winds through the city, is infamously brown. It was clear when the colonists started the city on Wurundjeri land, but now it’s said to run upside down. So, when American tennis player Jim Courier dived into the river after winning the Australian Open in 1992 and 1993, the rest of the city shuddered.
“One day,” O’Neill says, “maybe, one day, we’ll get the Yarra back to a situation where we can to swim in it. Anything is possible.”