Monday, November 03, 2008

Greenfield and Lucas on Recycled Water

The focus on recycled water continues at The Australian today. Unlike the last couple of days, today’s articles are much more positive and aimed at instilling community confidence in the use of recycled water to supplement drinking water supplies.

The first article below is an opinion piece from Prof Paul Greenfield, Vice-Chancellor of the University of Queensland and Chair of the Independent Scientific Expert Advisory Panel to the Queensland Water Commission.

The second is a news story featuring Queensland's Deputy Premier, Paul Lucas, marking the opening of Stage 2A of the western corridor recycled water project. Lucas took the obligatory swig of recycled water and made the obligatory positive remarks about the taste. I guess this is the recycled water version of baby-kissing during election campaigns. Its entirely meaningless, but the cameras need a tangible image.

Based on your existing point of view and underlying prejudices, I expect that you will think that its either about time someone took a proactive stance towards community discussion, or else that its all part of a sinister conspiracy-laden propaganda campaign. In either case, I’d be grateful for your comments.

Don't turn your nose up at purified recycled
Paul Greenfield
The Australian
November 03, 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.

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.

Minister takes on troubled water
Natasha Bita
The Australian
November 03, 2008

"BEWDIFUL!" Paul Lucas, Queensland's Deputy Premier, smacks his lips as he skols a glass of crystal-clear recycled sewage. "Absolutely beautiful. Great stuff."

By the time he had repeated the stunt four more times for the cameras yesterday, Mr Lucas had proven his bladder was as strong as his stomach.

"I feel a bit waterlogged now," he quipped, before calling a press conference to spruik the safety of recycled effluent, which will provide up to a quarter of southeast Queensland's drinking water by February.

Queensland Water Commission staff were right behind their minister - drinking bottled water.

But they would not let inquisitive media sample the recycled liquid, because it had undergone only five of the seven stages in the treatment process.

Mr Lucas's public display of support came as new questions were raised about the timing of the introduction of recycled water into the Brisbane, Gold Coast and Sunshine Coast supplies.

A Queensland Water Commission spokesman confirmed hospital waste would be put into the system for recycling into drinking water.

"Hospital waste is very closely regulated, so they have very strict rules about what goes down the drains," he said.

And Opposition Leader Lawrence Springborg has broken what was bipartisan support for the scheme.

Mr Springborg told The Australian that recycled water was being added "too soon" to the drinking supply.

The state's Liberal National Party has promised not to add recycled water to the drinking supply of southeast Queensland if the dams were over 40 per cent full, and they currently are 41.2per cent full.

He said that unlike state government policy to have recycled water as an integral part of the drinking supply, a Liberal National government would use recycled water only as a last resort.

"Nowhere around the world are they doing what's being proposed for Brisbane," he said. "We need to go into this very carefully, not the way the Government's rushed into this.

"You don't want to be adding recycled water to the system on a routine basis. It only takes one thing to go wrong and the whole system breaks down."

Mr Springborg said he anticipated that adding recycled water to the drinking water would become an election campaign issue.

The hundreds of families invited to inspect the Brisbane water purification plant at Luggage Point during a public open day yesterday were handed bottles of Coles spring water as they walked in.

"We haven't got any of our own bottled water because there's no place to do that at the moment," a Queensland Water Commission spokesman said.

"There's quite a lot of technical things to go through to put it into bottles."

Mr Lucas, Queensland's Minister for Infrastructure and Planning, brushed off claims that recycled sewage could not be guaranteed safe to drink, saying Queensland's waste-to-water would be better than Sydney and Canberra's drinking supplies.

He said industry was already using the recycled effluent from two other purification plants in southeast Queensland, to generate electricity.

But the effluent - filtered, purified and disinfected in a seven-stage process - would not be introduced into the drinking supply until February or March, after six months of certification and testing, he said.

"We want to make sure that everything is 150,000 per cent right, and it's been going very well," Mr Lucas said.

"If you're in Sydney and drinking water out of Warragamba Dam, it doesn't get any of this treatment. It goes into the river system from sewage treatment plants in Goulburn and Lithgow and goes into the Sydney supply.

"Canberra water waste goes into the Murrumbidgee system."

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