Recycled water - QWC puts an 'advertorial' in the Australian ...

Panic in the QWC camp leads to this advertorial in today's press.

Excerpt from the Australian (annotated):

Don't turn your nose up at purified recycled water

Paul Greenfield

3 November 2008

There is nothing more fundamental for a community than its confidence in a safe and reliable water supply. Southeast Queensland is implementing a $2.5 billion project to supplement dam supplies with purified recycled water: waste water that has been treated to the highest standard.

As the chairman of the independent scientific expert advisory panel scrutinising the project, I welcome any rational, scientifically based debate on these issues. After all, the panel includes world leaders in toxicology, microbiology, environmental science and advanced water treatment. The panel members, from Australia and overseas, have many years' experience in ensuring that drinking water supplies, regardless of source, are safe for communities to drink.

Some commentators have expressed concerns about the safety of purified recycled water based on information that is manifestly incorrect, not based on evidence and reflects existing prejudices. Such statements, coming as they do from so-called experts, directly threaten the community's understanding of water quality and cause unnecessary worry.

In The Australian last week, microbiologist Peter Collignon and urban planner Patrick Troy incorrectly stated that the Queensland project posed a health risk to 2.6 million people in the region.

I have no doubt the design of the Queensland scheme and its proposed operation meet or exceed international best practice to provide a safe, reliable source of water.

It was claimed by Troy and Collignon that the Queensland advanced water treatment processes, including microfiltration, reverse osmosis and advanced oxidation, would remove only 92 per cent of antibiotics. This is simply wrong. It represents a misreading of a 2007 study.

The present sewage treatment plants achieve reductions of about this level at just one barrier out of seven, even before the advanced water treatment process occurs. The data the panel has reviewed indicates the Western Corridor Recycled Water Project is consistently achieving better than the standards for the removal of antibiotics enshrined in the Public Health Regulations of 2005.

It was also claimed that viruses would get through the treatment process. But there are multiple barriers in the advanced water treatment process capable of removing viruses.

They are at least 100 times larger than the pores of the reverse osmosis membranes used in the production of purified recycled water, which effectively provide a molecular filter.

Purified recycled water is far cleaner than much of the existing water that reaches the dam from run-off over land.

It was further claimed there was "nowhere else in the world" where purified recycled water was being used to the same extent as it would be in southeast Queensland, where it will represent on average less than 10 per cent of supply from Wivenhoe Dam. But the advanced technologies being used (microfiltration, reverse osmosis and advanced oxidation) are all proven and in use across the world.

Similar schemes provide significant volumes in Britain, Belgium, Singapore, Los Angeles and Orange County in California. The most similar scheme has been operating for 30 years in the Upper Occoquan in Virginia, which is a leading water provider to Washington, DC. In that case, purified recycled water averages about 9per cent of the annual inflow to the reservoir and up to 80 per cent during droughts.

Contrary to Troy's claim, extensive studies, including epidemiological research, have been carried out and show no evidence of negative health impacts. Anyone with a dispassionate understanding of recycled water would recognise that treated effluent - straight out of a conventional sewage treatment plant - already supplements our urban water supply in Australia in unplanned schemes.

For example, Sydney's Warragamba Dam receives upstream effluent from Goulburn and Lithgow, Melbourne's Sugarloaf Reservoir receives effluent from the Lilydale Sewage Treatment Plant at Olinda Creek, and Adelaide's Mount Bold Reservoir takes treated effluent from Hahndorf.

Canberra's treated effluent enters the Murrumbidgee system, where it is diluted and extracted into the water treatment plants of towns downstream of Canberra. These systems work because the processes installed are appropriate for the risks introduced.

Clearly, different risks need to be managed in larger, planned schemes such as the Western Corridor Recycled Water Project - where a seven-barrier risk-management system applies and independent regulation occurs - but the same principle applies.

The membrane and ultraviolet oxidation technologies have been tried and tested in many applications worldwide.

Microfiltration is used in the food industry to purify, among other things, bottled water, medicines and fruit juice.

Reverse osmosis is used in desalination and home water-filtration units. Advanced oxidation uses strong ultraviolet light to destroy impurities and is used by doctors and dentists to sterilise surgical instruments.

After passing through these barriers, the water will be blended and diluted to a small proportion of Wivenhoe Dam water before being treated in the multiple stages of the water treatment plant at Mount Crosby, and then finally distributed to people's homes.

By law, this water must comply with Queensland's recycled water standards and regulatory framework. [And will be overseen by the VERY competent Qld Health Dept.]

The standards are based on nationally agreed guidelines adopted by state and federal governments, which were set after extensive scientific review and consultation.

When we debate recycled water, the key test we should demand is that it is safe and provides no greater risk to a community than its present water supply.

The independent scientific expert panel reviewing southeast Queensland's purified recycled water scheme has an ongoing role during the project's implementation to provide rigorous independent assessments to ensure this requirement has been met.

Paul Greenfield is chairman of the Queensland Water Commission's independent scientific expert advisory panel and vice-chancellor of the University of Queensland.

See - QWC advertorial.

Does Prof Greenfield really want to use Virginia as his prime example?

A State which is moving to prohibit the use of recycled water for any indoor purpose, including flushing toilets.

That's a very silly example to use.

And there's no guarantees. If it all goes wrong, too bad, you can't sue the Qld government and Prof. Greenfield will be long gone.

All care and no reponsibility ...