Yahoo Finance Sydney facing water shortage within 20 years if current growth continues, government predicts
Greater Sydney faces a 13% shortfall in its water supply within 20 years if the city continues to grow at its current rate while climate change makes rainfall less predictable.
A draft strategy on the city’s future water supply, released by the New South Wales government on Tuesday, says Sydney will need between 40 to 70 gigalitres extra within 20 years.
That’s on top of the current sustainable supply of 540GL of water a year – equivalent to slightly less than Sydney Harbour.
The new strategy aims to provide guidance on how the gap can be bridged and recommends increased supply needs to come within 5-10 years, and again in 2040, and again in 2060.
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It emphasises the importance of Sydney finding ways to increase its water supply from non-rainfall-dependent sources, acknowledging that climate change could reduce rainfall and make droughts longer and more frequent.
But it stops short of recommending Sydney begin recycling wastewater and reusing it as drinking water, as Singapore and many European cities do. Instead, it favours desalination, greater recycling of stormwater for non-potable uses, and greater efficiency programs.
“A secure water supply is vital and this plan ensures we are able to support economic growth as we recover from the pandemic and set the foundations for the future,” the state’s water minister, Melinda Pavey said.
“We need to plan now for how our growing city and region will use water wisely as Sydney’s population is set to grow to 7.1 million by 2041. During the most recent drought, our dam levels depleted faster than we’ve experienced since records began – at a rate of 20% per year.
“Thankfully our dams are now full, but we need to act decisively to secure sustainable water for the long-term – by exploring options for new water sources not dependent on rainfall, by conserving more, and by doing more with less.”
The strategy suggests that continued investment in comprehensive water conservation and efficiency programs can save up to 49 GL a year by 2040 at a relatively low cost.
A pilot study of 1,000 households found efficiency measures delivered a 20% reduction in water use per household and almost $190 in savings per year for household water bills.
The strategy paper suggests a further 20GL per year could be produced by running Sydney’s desalination plant full time – but this option could be controversial because of its power use which is currently offset.
It also recommended using recycled water for non-potable purposes to ensure greening and cooling of new suburbs.
“We need to get better at integrating land use and development planning with how we manage water in the landscape to improve liveability and amenity,” the report states.
In 2020, there were more than 70 stormwater harvesting projects across greater Sydney providing water for parks and gardens, irrigating sporting fields and golf courses, and flushing public toilets.
On using recycled water more broadly, the strategy suggests the government should continue planning for rainfall-independent options, including desalination and purified recycled water, but does not make it part of the 20-year plan.
Although it notes that the sewage system is reaching capacity and that 90% of wastewater in Sydney is treated and put out to sea, the strategy proposes only asking residents about their views on purifying water for drinking.
It notes this technology is used overseas.
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The draft water strategy treats the NSW government’s plans to raise the Warragamba dam wall as a flood mitigation measure for the Hawkesbury Nepean flood plain rather than extra water supply. The higher wall would do little to extend the water supply during during a prolonged drought.
The strategy also promises to improve water outcomes for Aboriginal people.
“We need to plan for and manage water to support Aboriginal rights, interests and access,” the strategy states.
“Water is deeply entwined with Aboriginal culture, health and wellbeing. While engagement with Aboriginal people around water management is improving, communities still lack access to water for cultural, social and economic purposes, and the complex water management framework in NSW can be difficult to understand and engage with.”
