Water futures

Despite what people may think, I don’t have any political ambition. I left private enterprise because it looked as if they needed a bit of common sense in Council. Similarly, I’m not a brave leader pushing ahead with a contentious plan to recycle water. I am someone who has been convinced by science that water can be purified to an acceptable standard, and I see the Water Futures - Toowoomba water recycling project as being a sensible step forward for this city.

There is no new water on earth. Through the water cycle, the same finite quantity of water has been circulating the earth for approximately three billion years. Unfortunately for humans, the water is not always in the places where we need it the most, and water supplies for cities and towns throughout Australia are experiencing a strain on this resource previously unknown to most of us.

Although a greater harvest of rainwater is possible for most places, this alone will not drought-proof a heavily populated and growing region, particularly if rainfall is unreliable. Obtaining a new water source for a community invariably means taking it from the potential sources of another district.

An additional factor influencing my enthusiasm for recycling is the need to take greater responsibility for the way in which, until now, we have used water once and then dumped it without a thought for the consequences.

In November 1991, Australia embarrassed itself internationally with the largest river toxic algal bloom in history. National media identified Toowoomba as the biggest contributor of nutrients to the river systems in Queensland and one of the sources responsible for the blue-green algae outbreak.

Toowoomba’s three water supply dams are now at historically low levels. Further bores are being drilled and, with Queensland Government approval, we plan to tap into the artesian basin as an emergency water source. The Toowoomba City Council is encouraging the installation of rainwater tanks in homes to lighten the burden on current water sources. We are also conducting a public education program aimed at changing people’s attitudes towards our most precious resource and to foster a “water-valuing” culture.

The legacy I wish to leave is one of taking responsibility. That is why I am advocating Toowoomba build an Advanced Water Treatment plant (AWT) to recycle our water for indirect potable reuse. I’ve seen this science at work, in Singapore and Orange County in the US, but the defining place for me was the facility I inspected at Upper Occoquan, Fairfax County in the US. There they have been recycling wastewater since 1978. At times, up to 90 per cent of the drinking water for 1.5 million people has been recycled and there has not been one negative medical side effect reported. Indeed, theirs is a community that is thriving and prospering because they have a reliable water source.

The technology available to Toowoomba for our AWT is far superior to that which has been used by Fairfax County for the past 28 years. Water purification processes and testing of water sources will continue to improve. It has been said that, due to improved screening methods, Giardia and Cryptosporidium seem more prevalent today than they were in former times, however, it is likely these parasites have always been around and that our immune systems cope very well in their presence.

The key to the Water Futures - Toowoomba project is in the use of multiple barriers. A multi-barrier process works on the principle of providing more that one means of removing any particular contaminant. It means we do not rely on just one treatment process to do the job and a failure of one component will not compromise water quality.

Experts agree that a multiple barrier system employing appropriate treatment technologies is capable of reducing the concentrations of contaminants to such a low level that any risk becomes negligible. This approach is supported by highly credible agencies such as the US Environmental Protection Authority and World Health Organization (pdf file 1.08MB) in their guideline documents.

Toowoomba’s treated wastewater, from the Wetalla Water Reclamation Plant, will be purified through the use of a multi-barrier treatment process incorporating:

• ultrafiltration;
• reverse osmosis;
• ultraviolet disinfection & advanced oxidation;
• surface water mixing at Cooby Dam; and
• extraction from Cooby Dam then conventional water treatment at Mt Kynoch Water Treatment Plant.