Perth to keep water sources local

Posted 7 July 2016

Fremantle HarbourLocal water supplies will dictate Perth's future development and population growth after the Department of Water ruled out piping in water from other regions.

In a recent report – Water for Growth: Urban – the State Government rejected previous proposals to supply Perth with groundwater from the south-west Yarragade or a pipeline from the Ord River.

“The report maps out the best future climate-resilient water source options for Perth, and piping in water over long distances is not one of them,” Department of Water Senior Water Planning Officer Dan Ferguson said.

“The water conversation has moved on a long way from this as a solution, as this report clearly shows.

“Planning for new urban areas must now consider the total water cycle and the water resources available locally.”

The report examined water supply and demand for Western Australia’s cities, towns and localities, both now and into the future.

It found  the state's urban areas will require at least an additional 250GL per year by 2050. 

As a result, groundwater recharge will be increasingly important, Ferguson said.

“Approaches include site-responsive designs that manage small rainfall events as close to the runoff source as practical, vegetation within the urban landscape and within drainage management systems, replacing impervious surfaces with pervious surfaces, providing overland flow paths, and retaining natural water bodies and natural drainage flow paths,” he said.

But inevitably, the drying climate will limit the availability of shallow groundwater to support future development, particularly along the Swan Coastal Plain from Perth to Busselton, Ferguson said.

“Local governments, schools, businesses and households will be making use of alternate water supply options to irrigate parks, gardens and recreation grounds in new urban areas planned for Perth, Mandurah and Greater Bunbury where shallow groundwater is not available,” he said.

Innovation in water re-use, recycling and desalination will need to continue.

“The Department of Water is supporting developers and local governments to consider managed aquifer recharge using treated wastewater and stormwater to meet some of our non-potable water needs. Managing aquifer recharge could also be a future option to address saltwater intrusion into coastal aquifers,” Ferguson said.

“In terms of scheme water, groundwater supported by new sources like desalination is very much the key to the medium to long-term future for our major urban centres.”

The State Government is calling on water professionals to help come up with solutions through its Water Innovation Program and partnership with the Cooperative Research Centre for Water Sensitive Cities