An American water expert has predicted a water crisis for Perth, claiming the amount of water the city uses is unsustainable.
Robert Glennon, a water law professor at the University of Arizona and author of several books on the subject in the United States, said it beggared belief that Perth gardens were so lush given the fragile nature of the water supplies.
Amid fresh revelations about the dire state and overuse of Perth’s biggest drinking water source - the Gnangara Mound - Professor Glennon said the city was headed for significant problems unless it learnt to use water more wisely.
He said he had been surprised at how much lawn was grown here.
“It’s not functional, it’s not being used for kids to play or anything,” he said. “It’s just sitting there looking green and taking water.
“I expected a dry city on the driest continent would be at the cutting edge of water conservation and instead I’m hearing stories about groundwater wells in everyone’s backyard and everyone has a lush lawn.”
Professor Glennon said the WA Government should avoid mistakes made by southern States in the US in drawing too much groundwater.
Although desalination plants would increasingly be an important source of water, the high cost and amount of energy used meant it was “not the panacea”.
He said the Government would be unwise to draw more water from the deeper parts of Perth’s aquifers.
Professor Glennon, who is visiting Perth courtesy of the University of WA, said groundwater systems were interconnected and drawing water from one part would only deplete another.
“The amount of rainfall has been decreasing in Perth for a couple of decades and the run-off and recharge into aquifers has also been decreasing, which means the amount of usable water is much less,” he said.
“When you have declining surface water, substantial problems of over-pumping groundwater supplies and enormous costs associated with increasing supplies through desalinisation, it strikes me Perth is facing a major water problem.”
