Dr Peter Coombes

NSW has outperformed the nation in water efficiency and according to the authors of a new report the reason is its BASIX rating system for housing and the rest of the country should emulate it.

Dr Peter Coombes, principal of consultancy Urban Water Cycle Solutions said the benefits of BASIX has been wider than improving home efficiency; it’s given NSW the edge in resilience in terms of water use.

He said an analysis of the nation’s water billing and use data he undertook with Michael Smit from the Rainwater Harvesting Association of Australia clearly showed how well BASIX is working. While consumption and bills are both increasing in Melbourne and other cities, in Sydney costs for households have remained relatively steady, as has water use.

Dr Coombes told The Fifth Estate that BASIX requirements around water efficiency should be part of planning frameworks around the country in order to improve the resilience of the urban form.

The stumbling block  is that the grey infrastructure agenda around water has some deep-seated similarities to the economic and political landscape of the coal, mining and energy sectors. As with fossil fuels, the casualty is the sustainability of our cities and the hip pockets of the households in them, Dr Coombes said.

Looking at the Australian Bureau of Statistics Water Accounting data on a national level, the analysis showed Australian households spent $2 billion more on water in 2013/14 than they did in 2008/9. The consumption data also showed an average 27 per cent more water being used nationally in 2013/14 compared to 2008/9.

The difference between the Sydney data and the national picture, Dr Coombes told The Fifth Estate, is that the measures implemented under BASIX – including the installation of rainwater harvesting for homes, increased use of grey water systems and mandating water-efficient appliances and plumbing fixtures – are working.

“Water use in Sydney stabilised a long time ago,” he said. “That is because of the sustainable buildings in Sydney. The substance of the urban form has some resilience in it. There was a change in the urban form in response to water resources and liveability issues.”

This is also evidence that the use of at-source solutions as part of a broader water resources management approach can negate the need for expensive grey infrastructure solutions like new desalination plants, he said.

Dr Coombes said that when he was chief scientist at the Office of Living Victoria, he questioned the size and degree of dependency on the desalination plant based on a systems analysis that showed measures at the household level could provide an effective solution to increasing the resilience of Melbourne’s water supplies.

He said he also made the same point to the Western Australian state government when undertaking independent analysis of the business case for exploiting another aquifer to ensure 100 per cent reliable water supply for outdoor uses.

Dr Coombes told the state government that outdoor water did not need to be 100 per cent reliable – people do find ways to manage.

What desalination plants in Adelaide and Melbourne have done is increase the cost burden on households due to the public private partnership model, he said.

Sydney’s was paid for in cash, outright, so is not constantly incurring costs that devolve down to consumers, Dr Coombes said.

In Victoria the numbers may be wrong

He said the numbers that were presented to the public by the Victorian government around the costs per gigalitre of water for desalination were questionable. They only include the cost of actually operating the plant, he said, not the costs of infrastructure to transport the water to the headworks, nor the costs of then pushing it through the system and into homes.

The actual costs of desalinated water in Melbourne, he said, were not between $1 and $3 a kilolitre per household, but more in the order of $9-$12 a kilolitre per household. He said the costs have been historically passed onto Melbourne water users not wholly in the fixed costs component, but also through an increase in sewerage charges.

“There has been a lot of negative messaging that nothing works [in terms of water security] but desalination,” Dr Coombes said.

“But desalination alone didn’t help in the [millennium] drought. What happened that got us through the drought was that people halved their water usage, they changed behaviour, installed rainwater harvesting and water-efficient appliances. That’s what contributed to saving our cities.”

The other aspect of desalination plants absent in government messaging around them, he said, was that they may not be climate change-independent.

They use a lot of energy, but sometimes include wind and solar energy sources.  The power to run them may be sourced largely from brown coal power plants in Victoria, and black coal in NSW. These power plants not only generate emissions, they use a large quantity of water while doing so.

The impact of the plants on the electricity grid is something that needs careful consideration, Dr Coombes said. It may cause problems in an already stressed electricity grid.

The whole push for desalination as the only solution is hurting a lot of things, he said, including the green infrastructure and sustainable buildings agendas. The grey infrastructure approach may also be increasing the revenue and monopoly power of water authorities.

“There is a perception from some in authorities about a need to to protect their monopolies and grow their profits and build more centralised infrastructure because that is the only thing that works,” Dr Coombes said. “However multi-scaled solutions can also improve the viability of water authorities.”

He said that analysis of water bills where there is not a “multi-scaled” approach to water resource management shows that there is a rising cost in terms of household budgets from the increasing price of providing water via the traditional grey infrastructure approach.

A multi-scaled approach, by contrast, means a mix of water harvesting at the household scale, water efficiency in using water, ways of capturing stormwater and using it in maintaining green infrastructure and reducing impacts on catchments, and implementing Water Sensitive Urban Design. These solutions within cities improve the resilience and sustainability of the centralised paradigm.

So are rainwater tanks safe or not?

Dr Coombes said that rainwater tanks, as specified in BASIX, have recently come under fire for being a public health risk. State governments in particular have been the focus of anti-tank lobbying.

Dr Coombes, whose research has included microbiology, economics and systems science, said his response was to directly query every state and territory’s chief medical officer [or a representative] to ask if regional hospitals in areas where there is a high level of rainwater tank usage have been full of people with typhoid and other diseases people are claiming tanks foster.

The answer was no, they haven’t.

He said the whole situation around water, including the economic models policy and planning rely on, has a lot in common with the kind of questionable modelling, lobbying and power plays we’ve seen around coal, the mining industry and governments.

As our cities grow, he said, the costs of servicing that growth in terms of water infrastructure – including wastewater, stormwater management and potable water – will continue to grow exponentially. The only way to fix it, he said, is to “solve it at the source”.

“We need to move to an approach that solves part of the problem in a decentralised manner.”

He said the things BASIX had demonstrated work should become part of planning systems across the whole country, and that the systems need to include clear targets, accountability and guidance – not just lofty sounding principles.

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