The 4350water Blog highlights some of the issues relating to proposals for potable reuse in Toowoomba and South East Qld. 4350water blog looks at related political issues as well.

Tuesday, March 17, 2009

ABC's Catalyst program recycles Anna Bligh's recycled water ...

QWC's John Bradley is very careful with his words.  He won't say there's no risk with drinking recycled water - just that it 'poses no additional risk'.

Catalyst - Water Recycling


12 March 2009

TRANSCRIPT

NARRATION:
You’d expect a microbiologist’s pool to be pretty clean.

Dr Helen Stratton:
The water looks good, doesn’t it, which is just as well.

NARRATION:
Like any mum, Helen Stratton wouldn’t let her kids near water that might make them sick.

Dr Helen Stratton:
In actual fact, I took them out of the swim lessons because I wasn’t happy with the water quality.

NARRATION:
Keeping an eye on the kids goes beyond pool safety. Helen’s one of many Queensland scientists working to ensure the safety of drinking water recycled from treated sewage.

Dr Helen Stratton:
I think this idea of toilet to tap is a really bad misconception, it’s way past that. The water will be cleaner than any of the water ever going into the dam.

NARRATION:
But not all microbiologists agree that the technology is safe.

Prof Peter Collignon:
If you use water as your source from sewage you’re starting off with a thousand to a million times higher concentration of viruses, bacteria and probably drugs than it is even in a polluted river. So you’re starting off with a much more dangerous water source.

Dr Helen Stratton:
We’ve had a hundred years of protecting public health by making sure we have clean drinking water. Now we’re not about to undo that.

Snow Manners:
We don’t know what it is that we don’t know about. There is destruction confronting us, therefore we must drink from the sewers.

NARRATION:
It’s a public debate about science that hasn’t changed since 2006…

Woman in Toowoomba:
Toilet water is toilet water, dam water I don’t think has ever been toilet water ever, so, yeah…

NARRATION:
…when I visited my hometown of Toowoomba, the first city to vote on water recycling.

Mark Horstman:
Mr Berghofer, the yes campaign says that science was the loser today, so who won?

Clive Berghofer:
Oh come on, no, come on.

Snow Manners:
The community does not need to know anything about the science.

NARRATION:
Despite a 60 percent vote against it, Toowoomba can now plug into a brand new water recycling scheme that covers all of south-east Queensland.

John Bradley:
There’s been a nine billion dollar investment in interconnecting pipelines and desalination and recycled water technology. It’s certainly massive, and probably it’s only comparable project is the Snowy Mountains scheme.

NARRATION:
At full capacity, water recycling can purify more than 200 million litres every day, using secondary treated waste from six sewage treatment plants.

Troy Walker:
We measure about 350 contaminants in the treated water. We wanted to target our testing on the sorts of things that we found were coming into the plant to be treated in the first place…pharmaceuticals, herbicides, pesticides, microbiological contaminants, and even radionuclides.

Usually all of these nasties end up in our rivers for others to drink downstream.

Keith Davies:
The water that used to go into the rivers and the bay is our feedstock, that’s our inflow. And we take that water and take out the contaminants.

NARRATION:
What makes this advanced water treatment plant different are the three extra steps it adds to the existing treatment process.

Mark Horstman:
What’s happening in these pipes?

Keith Davies: This is our microfiltration unit. This is barrier 3 of the 7 barrier process.

NARRATION:
Each tube is packed with thousands of fine hollow fibres that filter out tiny particles and most microbes.

Keith Davies:
Under very great pressure the water is forced through those tubes. They have holes in them 1/300 the size of a human hair, and this takes out the particulates.

NARRATION:
Only then is the filtered water ready to enter the reverse osmosis tubes, the most important part of the process.

Keith Davies: This technology is basically the same technology that’s used in desalination.

NARRATION:
At its core are membranes so thin that a stack of five thousand of them would be only one millimetre thick. They’re bound into stacks, interleaved with spaces for water to flow through, and rolled tightly into cylinders. Spiralled inside these fifty tubes are more than a hectare of membranes. They’re not like sieves with tiny holes. Rather the membranes work like a massive artificial kidney, drawing water out of the passing waste stream.

Keith Davies:
Water diffuses through the membrane to come out as hydrogen and oxygen basically.

Mark Horstman:
That must take a lot of pressure?

Keith Davies:
It does take a lot of pressure. This is the highest powered part of the plant.

NARRATION:
Down at the atomic level, water molecules are attracted to the membranes and pushed through by up to 20 atmospheres of pressure. But viruses can only get through if there is a hole in the membrane. To guarantee safety, the system is designed for overkill.

Troy Walker:
Not very much can go wrong, to be honest. Most of the system is automated.

NARRATION:
It’s when things do go wrong that worries Professor Collignon.

Prof Peter Collignon:
My main concern is that it may not remove all the viruses in particular but other germs and also all the drugs we need to make it safe for people to drink all the time.

Prof Peter Collignon:
Trust me I’m an engineer is worse than trust me I’m a doctor.

Mark Horstman:
Trust me I’m a microbiologist?

Prof Peter Collignon:
Trust me, I’m a microbiologist.

Mark Horstman:
Have you done your own research, your own testing of this kind of water?

Prof Peter Collignon:
No we don’t. Because we’re not that sort of laboratory.

NARRATION:
This is the lab in Queensland that does. For more than a year, a small scientific army has been testing samples from the advanced water treatment plants for chemicals, microbes, and viruses.

John Bradley: The people that are actually doing research in this area have concluded that this poses no additional risk to our community.

NARRATION:
In addition to this work, Helen Stratton’s university research is developing more rapid techniques to measure pathogens in water.

Dr Helen Stratton: I’m really comfortable as a microbiologist – and I’m quite paranoid about what I drink and what I eat – I will be drinking the water.

NARRATION:
But there’s plenty of doubt about that, out in the suburbs.

Man with 5 kids:
Nuh. Just doesn’t make any sense to me. Anyone that feeds their kids water like that, got rocks in their heads mate.

Woman:
I don’t really like the idea of drinking it very much.

Brothers and sister:
Not much we can really do. Yeah. I guess you put your life in their hands really.

Mark Horstman:
This is the Wivenhoe Dam, where much of south-east Queensland gets its drinking water from, and it’s at the centre of the recycled water debate. Now as you can see right now it’s only about a third full. And even though there’s up to one hundred million litres of pure water that’s ready to be pumped into here every day, while there’s public opposition to the plan, the water’s just not going to flow.

NARRATION:
Heavy rains have eased the drought, and topped up the water supplies. So the government decided to add recycled water to the dam only in emergencies – for now.

Dr Helen Stratton:
It’s not about switching it on or off. I think we need to make the decision to do it or not to do it. The government has agreed that it's a safe process.

NARRATION:
And that’s the key issue. The treatment plant has to reduce viruses by at least a billion times, or in mathematical terms, by log 9.

Prof. Peter Collignon:
To achieve safety from a viral point of view we’ve got to get to log 9 or more.

NARRATION:
To put it another way, the chance that a virus is left behind is one in a billion.

Prof. Peter Collignon:
If we look at log 9 which is a billion-fold reduction that represents a 99.9999999 reduction. In other words…

Mark Horstman:
…percent reduction?

Prof. Peter Collignon:
…percent reduction. Which sounds very impressive. But that’s the sort of reduction we have to achieve all the time.

NARRATION:
That’s exactly why at the advanced treatment plant, they monitor the performance of each stage every second.

Troy Walker:
This is one of our critical control points for the plants. It gives us an idea of how intact the membranes are, it gives us a guarantee.

Mark Horstman:
What happens if there’s a tear in the membrane, and it goes above a certain level?

Troy Walker: If this level goes above our critical level, it will raise an alarm, and shut the plant down.

Mark Horstman:
Immediately?

Troy Walker:
Immediately.

NARRATION:
Even if the alarms do go off, any lingering viruses or toxics still have to get past a lethal combination of hydrogen peroxide and ultraviolet radiation.

Keith Davies:
The intensity of the UV is somewhere around 300 times that of the sun. This is a very similar technology to what’s used in the medical industry for sterilisation.

Mark Horstman:
What can survive?

Keith Davies:
Nothing can survive this.

NARRATION:
What they have to achieve is the national target for recycled water safety – that’s log 9.5 reduction of viruses. Data provided to Catalyst show they can, removing viruses even up to log 12.

Mark Horstman:
If they’re meeting that target, is that OK?

Prof Peter Collignon: Well, I would be reassured by that because a lot of the other plants haven’t even achieved that. But I still think there’s a problem even with those guidelines. They run on 95 percentiles. Now again, that means one in 20 may not meet it. To me, that’s not stringent enough.

NARRATION:
That’s why Queensland legislation requires the safety target to be met 100 percent of the time, and reported if they don’t.

John Bradley:
The science speaks for itself. There’s no doubt that this can be a safe and reliable source of drinking water supply, but there is a way to go to actually convince the community of the evidence that’s before them.

Dr Helen Stratton:
The water’s safe and it’s safe beyond doubt and that there’s safety checks in place to know if it wasn’t going to be safe.


Catalyst does a repeat of clipping the Snow Manners comment so it seems like he says that Toowoomba doesn't need to know about the science.  Here's what he really said: Catalyst - What was really said.

And don't try suing the Qld government if something goes wrong.  Anna Bligh and Kerry Shine made sure you can't sue the government if the process fails.  The government doesn't even need to notify the public if something goes wrong.

If Anna Bligh wins on Saturday, you can bet her spin doctors will do everything in their power to bury any problems with the system.

It make one wonder - if the recycled water is so great, why isn't Anna Bligh running election ads about it ...

5 Comments:

Anonymous Anonymous said...

As I thought a big push for recycled water - Labor Party supporters do not like the idea of recycled ware flowing through their taps - but of course Anna and Co are keeping low key on that issue

Lets just hope that the dams overlow in the coming months

7:53 PM, March 17, 2009

 
Anonymous Anonymous said...

This comment has been removed by a blog administrator.

3:45 PM, March 18, 2009

 
Anonymous Don't vote Anna said...

Remember: a vote for Anna Bligh's team is a vote to drink from the sewer!

4:42 PM, March 18, 2009

 
Blogger alisha said...

This comment has been removed by a blog administrator.

4:44 PM, March 18, 2009

 
Anonymous administrator2 said...

Singaporean spam deleted.

6:08 PM, March 18, 2009

 

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