Water Running to Waste Down Under

SYDNEY, Australia, July 25, 2002 (ENS) - Australia, the world's driest continent, currently wastes 92 percent of its city runoff and 86 percent of its effluent water. a prominent water scientist has warned. It is time to develop a national approach to re-use of water, says Dr. Peter Dillon, from the Commonwealth Scientific Industrial Research Organization (CSIRO), a government agency.

"The amount of water going to waste is large," says Dr. Dillon of CSIRO Land and Water. "It constitutes a loss to industry and the environment, inhibits future development and adds to pollution. The fact that we re-use barely eight percent of the potentially available water is a reflection of our failure to get our act together on this vital national issue."

Dr. Peter Dillon of CSIRO Land and Water (Photo courtesy CSIRO)

In addition to conservation of rain water, there are four kinds of water with potential for re-use: stormwater, treated sewage effluent, treated industrial discharges, and gray waste water from household laundry and bathroom use.

The water expert sees how these waters could irrigate city parks, verges, ovals and horticulture, could be used for industrial purposes, for cooling water, for toilet flushing or for environmental purposes.

"The main barriers to re-use of water in Australia are issues of public confidence, health, the environment, reliable treatment, storage, economics, the lack of relevant regulations, poor integration in water resource management, and the lack of awareness," Dr. Dillon observes.

Tile drainage pump flow into drainage channel, Griffith, New South Wales. (Photo by Bill van Aken courtesy CSIRO)

Still, this remains a small proportion of the amount of the water still running to waste.

The Urban Water Resources Centre at the University of South Australia worked on a home water re-use project that shows how ordinary householders can put these concepts to work to save water.

The Intelligent Home concept at Regent Gardens, South Australia, involved collaboration between A.V. Jennings Pty. Ltd, innovative Australian businesses, and groups within the University of South Australia. The Intelligent Home is a modern semi-detached dwelling, which, among some 300 environmental features, has two independent water management systems incorporated into its design.

A roof runoff collection system for hot water supply was installed, with mains water only used as make-up water when the raintank is empty. The rainwater is collected in a tank and pumped to the hot water “head-tank” in the roof of the home. It is heated to 65°Celsius, thereby destroying roof originating bacteria and rendering the supply safe for drinking.

Resident of the Intelligent Home surveys the reedbed system that purifies graywater. (Photo courtesy University of South Australia Urban Water Resources Centre)

The combination of the rainwater use and graywater treatment and re-use plans are expected to decrease mains water use in the home by at least 30 percent.

"One of the major obstacles to progress is that there is no national body or funding organization dedicated to water re-use, despite unanimous support for the idea from the Australian Water Association's Water Recycling Forum," Dr. Dillon says.

He says the risks of a public health or environmental failure of a water re-use project are higher from a fragmented and uncoordinated approach than they would be under a single body.

Australia, as the driest continent, could be a world leader in water conservation and re-use and a top exporter of technology and know how in this area, he says.

"Water will be in critically short supply for more than a third of the earth's population during the 21st century. By solving our own problems we will not only help Australia - we can also contribute ideas and technologies for addressing one of the most vital aspects of human survival."