Peter Collignon is a Professor in the School of Clinical Medicine at the Australian National University. He is also the Director of the Infectious Diseases Unit and Microbiology Department at the Canberra Hospital.
Prof. Collignon is opposed to current ACT Government plans for the development of an indirect potable water recycling scheme for Canberra. We have discussed his views here in some detail previously.
Today Prof. Collignon has asked me to post the following more detailed discussion of his point of view. I am very pleased to do so and, as always, welcome your response.
Recycled sewage; why put ourselves at needless risk in Canberra?
Prof Peter Collignon
April 27th, 2007
I have appreciated the various informative and balanced discussion that has occurred on this website on this issue.
I am not against treating and recycling sewage in some circumstances. I just believe that our health is best protected by trying to keep all human (and preferable animal) faecal material out of drinking water. We should not put treated sewage into our drinking water unless we have no other options (which I agree in many areas of the world is the case). If it is already in our drinking water (ie contaminated rivers) then we should use systems to make drinking water as safe as possible. We should only recycle sewage into drinking water when there are not alternate safer water (and cheaper) sources available.
A number of you have asked why I needed to asks questions about the size of membrane pores, Reverse osmosis performance etc. I am not a water expert but rather a practicing clinical microbiologist, Infectious Diseases physician and clinical academic and so asked these questions from first principles. The reason I had to ask these questions is that when I entered this debate, that type of information was not made available by the local authorities when they announced this proposal (and is still not readily available). It still appears to me that they (ACTEW) and our local government have already decided to proceed with recycling sewage but without allowing ready access to adequate and meaningful technical information on the proposed performance. This is especially important from a virus and drug extraction point of view plus also what will be the safety fail-safe and testing systems. I have found out a lot more information over the last few weeks form people such as yourselves (eg Dr Khan). However people in Canberra are not being given anywhere as much information as I believe should be made available for those interested.
My belief remains that in Canberra, the proposed recycling of about 9 GL per year (and rising to 18 GL) of sewage and then pumping this treated water back into our domestic water supply reservoirs is a needless human health hazard. In the ACT, in most years, there are large and excess volumes of water available in our rivers and streams and we have the ability to store this water in dams for a “rainy day” (or reality - “non-rainy days”!).
Numerous infectious diseases outbreaks related to drinking water are still common in many developed countries including the US, Canada and Europe, even though they have advanced water treatment systems. Outbreaks result from pathogens found in high numbers in human or animal faeces and include numerous viruses, bacteria and protozoans (eg giardia). I am also concerned about the viruses and other pathogen we have still not discovered. While I acknowledge that our “recycled sewage” will likely be treated so that it is “safe” to drink. However further information on the process I have received over the last weeks have done little to lessen my concerns if this water was to be used in drinking water here as it can never be 100% safe. Reverse osmosis only seems to remove about 99% of salts (a log 2 reduction). If it can’t remove all salts how can we be sure it will remove all viruses?
My belief remains we should not take the risk inherent in putting recycled sewage into our water supply, unless we have no other choices. No matter how good your system, things occasionally go wrong with both the performance of equipment and with the people running equipment. I remain convinced that Canberra has lots of other choices to find 9 GL of water that are safer, more economic and more environmentally friendly than this proposal. We still here are using “drinking” water released from the Googong dam to fill Lake Burley Griffin. Surely our current treated water could be used for this purpose and others that does not require potable water quality and thus lower the amounts of water we need to release from our dams which would then stay filled for longer.
Public statements from ACTEW show that they are planning for a worse case scenario where there is a sustained 90% reduction in the water inflows into our dams over many continuous years (and thus the need for recycled sewage). I don't believe CSIRO or any other group are saying this is very likely scenario. The 10 year long-term moving average rainfalls from the Bureau of Meteorology (BOM) website, show no sustained drop over the last 120 years in South East Australia rainfall despite this recent severe drought. 2006 was one of our worst years on record with a 90% reduction in inflows to our dams, but there have been numerous other severe drought years in the past. Despite and despite this our dams are still now 33% full. Australia will continue to be a land of droughts followed by floods
Mr Michael Costello, Managing Director, ACTEW Corporation, in a recent letter has stated “the balance of probability is that the extremely severe conditions of 2006 will not be repeated, and that there will be sufficient water to meet our needs without having to use recycled water.” However he went onto say we cannot rely on long-term averages and we may face extreme inflow problems. Even though the risk is small “we cannot afford not to take out insurance against it. And that is how we should see the recycled water project – as essential insurance which we hope will seldom, if ever, have to call upon.” This seem to me to clearly say we will only use this recycled sewage water in very dry years and I presume also only when our dams are also very low (<10%). Obviously if we don’t use any recycled water from sewage there cannot be an increased risk to the Canberra community and so from an Infectious Disease point of view I can hardly raise any objections. However this is likely to mean, that this $150+ million facility may only be used once every 30 years - or probably not at all. This is potentially very expensive "insurance". The cost of this facility is likely to be over $1,000 per Canberra household and this cost I presume will be borne by householders.
In Canberra, if we include the Cotter dam catchments, then there is normally about 210 GL of water that inflows into our dams on average per year which we could use use for domestic water supplies. The small Cotter dam is the lower of the 3 dams on the Cotter river, (others are the Corin and Bendora) and thus the only dam on that river where any releases and “spills”, means the water is then lost from the domestic water supply. With the water restrictions we now have in place, about 50 GL of water is removed for domestic use (and we return about 35 GL after recycling to the Murrumbidgee) and about 9 GL is used as legislated environmental flows as releases from the Cotter and Googong Dams (5.5 and 3.5 GL respectively). Thus from what I can see, we are only in big trouble if we consistently receive less that 60 GL per year into our dams (ie a 66% continuous drop in inflows). As far as I am aware no major scientific group is predicting that as a likely long-term scenario. Except for 2006, in every other year during our prolonged drought since 2001, we had inflows into our dams of more than this.
Even if we do recycle 9 GL per year of our sewage into our water supplies, this water will be put into the very small Cotter dam (only 4 GL capacity). However in 2006 (one of our driest years ever) this dam was full or overflowing for 5 months of 2006 (July to November). Hence unless a new and bigger Cotter dam is built, any "recycled" sewage will be "wasted" water from a domestic consumption point of view unless we can pump it out faster than we put it in, which we appeared incapable of doing in 2006. Most of this recycled water will likely to just flow over the top of the dam. In 2006 we did not manage to avoid major spills from the Cotter dam. It is difficult to find figures but if 13.5 GL was released from the Cotter dam in 2006 (ACTEW figures) and only 5.5 GL as environmental releases, I presume that 8 GL spilt over the top of the dam. It would be very useful for ACTEW to release their figures for both mandated environmental releases as well as their estimates of yearly “spills” over the top of the Cotter dam for the last 10 years. This dam can apparently not be allowed to fall below 90% capacity as otherwise some native fish in the Cotter dam become endangered. However this means that frequently this dam will overflow.
Thus irrespective of the health risks, I can't see how it is sensible to consider starting this proposed sewage recycling project until we have a bigger Cotter dam to receive the recycled water - yet the stated plan is to have this sewage recycling system operating 3 years before any new dam is constructed. If a bigger Cotter dam is built as planned presumably that will fix this water shortage problem and without the need to recycle 9 GL of treated sewage into our drinking water. The bigger dam will presumably help store for future years the large volumes of "pristine" catchment water currently lost as “spills" over the smaller Cotter dam.
My view remains that this proposal to recycle sewage should not proceed in Canberra. We have ample flows of much safer water that could be stored and used for human consumption. If we proceed and put this water into our drinking water when we have other options, we will be creating a human health hazard needlessly for our population. It will also be at great financial cost and without any obvious benefits to our environment.
Prof Peter Collignon.
Infectious Diseases Physician and Microbiologist
Director Infectious Diseases Unit and Microbiology Department, The Canberra Hospital.
Professor, School of Clinical Medicine, Australian National University.
Friday, April 27, 2007
Tuesday, April 24, 2007
Howard endorses Brisbane IPR Scheme
If you’ve been following the development of water recycling plans in South East Queensland, you will know that the Beattie Government has been requesting support from the Commonwealth Government to help fund the Western Corridor Recycled Water Project.
The project involves building a pipeline between six wastewater treatment plants in Brisbane and Ipswich to three advanced water treatment plants. The water would then be delivered to two major power stations, industry and farmers, as well as supplementing the drinking water supply from Wivenhoe Dam.
The Commonwealth Government has set up the National Water Commission (NWC) to assist with funding for important iconic (or at least innovative) projects. Federal Environment Minister (and Water Minister) Malcolm Turnbull has the job of overseeing NWC decisions and activities.
Throughout the last few months, the Commonwealth Government have been suggesting that they may support the Western Corridor project, but have consistently argued that insufficient financial information had been provided in order for them to make a decision. As Turnbull told the Sunday Mail last week:
"From the outset we have asked for a complete set of financials for the project, which includes an up-to-date estimate of construction costs, operating costs as well as revenues" and "We need to know the impact on water prices from the proposed grant and who it will benefit. The major customer for the Western Corridor Project will be several State Government-owned power stations, so it is not clear whether the grant will actually benefit Brisbane's residential water users."
The political stand-off appeared to come to an end today with Prime Minister John Howard and Turnbull pledging to support the project. The Courier Mail reports that the Commonwealth Government will invest $408 million in the $1.7 billion recycled water pipeline.
Mr Howard said "I want the project to go ahead. I want it to be a success".
Not surprisingly, Queensland Premier Peter Beattie welcomed the announcement. He said "That's great news for two million Australians who are battling the worst drought in their history - it's a big win for Queensland".
I’m not sure whether the NSW Government have applied for Commonwealth assistance for their $1.9 billion seawater desalination plant at Kurnell. However, it remains to be seen whether such support would be forthcoming.
ANZAC Day tomorrow. I don’t think I’ll wish anyone a “happy ANZAC Day”, but at least try to find a moment to reflect on the 8000 diggers who lost their lives. Or perhaps the full 60,000 diggers who died during WWI. Or else the (at least) 8 million soldiers from all countries who died. To that you can add the countless more civilians. Hmmm... why not just think about the stupidity and futility of war in general? Happy ANZAC Day indeed.
The project involves building a pipeline between six wastewater treatment plants in Brisbane and Ipswich to three advanced water treatment plants. The water would then be delivered to two major power stations, industry and farmers, as well as supplementing the drinking water supply from Wivenhoe Dam.
The Commonwealth Government has set up the National Water Commission (NWC) to assist with funding for important iconic (or at least innovative) projects. Federal Environment Minister (and Water Minister) Malcolm Turnbull has the job of overseeing NWC decisions and activities.
Throughout the last few months, the Commonwealth Government have been suggesting that they may support the Western Corridor project, but have consistently argued that insufficient financial information had been provided in order for them to make a decision. As Turnbull told the Sunday Mail last week:
"From the outset we have asked for a complete set of financials for the project, which includes an up-to-date estimate of construction costs, operating costs as well as revenues" and "We need to know the impact on water prices from the proposed grant and who it will benefit. The major customer for the Western Corridor Project will be several State Government-owned power stations, so it is not clear whether the grant will actually benefit Brisbane's residential water users."
The political stand-off appeared to come to an end today with Prime Minister John Howard and Turnbull pledging to support the project. The Courier Mail reports that the Commonwealth Government will invest $408 million in the $1.7 billion recycled water pipeline.
Mr Howard said "I want the project to go ahead. I want it to be a success".
Not surprisingly, Queensland Premier Peter Beattie welcomed the announcement. He said "That's great news for two million Australians who are battling the worst drought in their history - it's a big win for Queensland".
I’m not sure whether the NSW Government have applied for Commonwealth assistance for their $1.9 billion seawater desalination plant at Kurnell. However, it remains to be seen whether such support would be forthcoming.
ANZAC Day tomorrow. I don’t think I’ll wish anyone a “happy ANZAC Day”, but at least try to find a moment to reflect on the 8000 diggers who lost their lives. Or perhaps the full 60,000 diggers who died during WWI. Or else the (at least) 8 million soldiers from all countries who died. To that you can add the countless more civilians. Hmmm... why not just think about the stupidity and futility of war in general? Happy ANZAC Day indeed.
Monday, April 23, 2007
A brief bout of trumpet blowing
There was an article about water recycling in the Canberra Times today. Unless you live in Canberra, you probably didn’t see it since it doesn’t appear to be available on the newspaper’s website. I retrieved it from a media database called Factiva, for which you need a subscription to access, so I can’t provide a link.
However, I couldn’t resist posting it here since it mentions this blog. It’s a case of the media discussing this blog discussing the media (and now this blog discussing the media back again!). There must be term for this. I mean a polite term!
As always, I’d be grateful for your opinions...
When is water fit to drink?
The Canberra Times
23 April 2007
UNIVERSITY of NSW water quality scientist Dr Stuart Khan doesn't think Canberra residents are being squeamish in objecting to ACT government plans to add treated effluent to their drinking water. ''Squeamish? Definitely not, it's a natural response that's worked well for the human species in terms of evolution we know instinctively to avoid water that's contaminated. ''I accept the 'yuk factor' as an objection. People should be concerned about the quality of their drinking water,'' he says.
Khan, a senior researcher at the University of NSW centre for water and waste technology, isn't opposed to recycled water schemes. In fact, he's been one of their most articulate champions but argues they can't be touted as foolproof or without human health risks. ''Scientists can never say there's no risk with recycled water, but most risks can be effectively managed if advanced treatment processes are employed.''
Several years ago, Khan conducted the first survey of pharmaceuticals in Australia's waterways as his doctoral thesis. He looked at which drugs anti-depressants, contraceptive pills, anti-inflammatories and antibiotics were being prescribed at high enough concentrations to be detected in municipal sewage. Studying inflows and discharges at a sewage treatment plant in western Sydney, Khan found removal of these biologically active compounds was variable, depending on methods of wastewater treatment. He told the ABC's ''Earth Hour'' in 2004 that pharmaceutical drugs were entering the environment at ''pretty much the same mass per year'' as pesticides and it was time to ''look at setting, or at least talking about, arguing about, what are acceptable limits that a sewage treatment plant can emit.''
Earlier this year, he co-authored a report for the Local Government Association of Queensland on the risks and health effects of adding highly treated wastewater reclaimed from municipal effluents to drinking water. The report says the microbial and chemical quality of water intended for recycling ''is generally very high'' and risks associated with potable reuse ''while never zero, are successively decreased with increasing levels of treatment.'' But it also says the range of potential contaminants in municipal wastewaters ''is significantly greater than in well protected environmental waters'', and concentrations of these contaminants can fluctuate, making them difficult to detect by conventional water monitoring systems. ''While studies undertaken overseas bode well for the safety of recycled water generally, exactly how effectively these studies can be translated to potential Australian schemes is less clear. Water sources will differ and water treatment processes will differ,'' the report says.
In recent weeks, Khan has been keeping a close eye on political events in the ACT, posting commentary on his water recycling discussion blogsite ( www.waterrecycling.blogspot.com ). Former ACT Planning Minister Simon Corbell was stripped of the portfolio after calling for a more cautious approach to water recycling, following concerns raised by Canberra Hospital infectious diseases specialist Professor Peter Collignon over the risks of prescription drugs persisting in the waster supply. ''I'm concerned that the recent water policy is a fait accompli ... I think as a government we need to be more critical of what's being proposed,'' Corbell said. On his blog, Khan wrote: ''One might think this would be perfectly reasonable and, in fact, prudent position to take especially given Collignon's expression of concern. Absolute confidence that public health will be protected is vital ... I am perhaps idealistic enough to think that open debate should be encouraged, rather than crushed. If a Planning Minister can't engage in a public debate about water management and public safety, who can?''
During the NSW election campaign, former state Liberal leader Peter Debnam downed as glass of ''recycled'' water as part of a taste-test media stunt to launch his $955million water recycling plan. There were political red faces when it was later revealed by water experts that the water used in the taste-test came from Sydney Water's North Richmond filtration plant on the Hawkesbury-Nepean river. Sydney Water confirmed the water was produced from run-off, and was not recycled water.
Toowoomba's rejection of recycled water has been criticised as ill-informed and the result of a fear campaign exaggerating health risks. Khan was involved in the public debate as a supporter of water recycling schemes but says it's wrong to portray Toowoomba residents ''as a bunch of Luddites incapable of accepting scientific fact.'' He argues the major factor for many No- voters in Toowoomba had ''little to do with any suggestion that there may be something fundamentally wrong with the concept of planned potable water recycling.'' What scuppered the scheme was lack of community consultation and ''a perceived unwillingness'' of the council to consider alternative water management options. ''These factors left the community feeling disempowered and generated suspicion of the council's motivation,'' he writes. ''There are many lessons to be learned from Toowoomba. If we dont take them seriously, we are doomed to repeat the mistakes. Observing people in the media and on this blog lashing out at Toowoomba residents for being stupid, naive and irrational is not encouraging.''
Last week, Australian National University professor of water resources, Ian White, dismissed the ACT Government's plans to add treated effluent to Canberra's drinking water as a cynical way ''to make money by pushing up water prices.'' He also accused ACT Chief Minister Jon Stanhope of a potential conflict on interest between his new role as environment minister and his financial obligations as principal government shareholder of water utility Actew.
Stanhope dismissed the suggestion as ''extremely offensive'', saying he was fully aware of, and accepted, his ministerial responsibilities to distinguish between the dual roles. But White and former Actew chief engineer Cary Reynolds have raised questions about the cost-benefit analyses that under-pin the government's push to introduce recycled water. ''It's a very expensive option and the government haven't adequately explained why it's necessary or what it will cost consumers. Where's the economic debate? We seem to have skipped that,'' White says. He claims the government's plans to introduce recycled water ignore the recommendations of a previous Actew report in 1994 which outlined a 50 year strategy to guide Canberra's water supplies. The report, which involved two-years of community consultation, was designed to be reviewed and updated every five years with new data, but was shelved in 2004 and replaced by the government's pared-down Think Water Act Water strategy.
Reynolds was one of the authors of the 1994 report which won national awards for innovation and points out more than 97 per cent of those surveyed were in favour of using treated water to irrigate parks and gardens. Only 20 per cent supported use of treated and recycled effluent as drinking water. Reynolds believes a less costly solution to Canberra's water problems is to ''mine'' effluent from the sewer and stormwater systems, using treated effluent for irrigation.
Effluent mining is already being used to irrigate the Duntroon sports ovals, and the system could be expanded across the city at a cost of about $5million to build two treatment plants, he says. ''Do we need to go to recycled drinking water because of the drought? Probably not if we remove irrigation demands from potable water by using treated effluent, and place more emphasis on community education. We need to tell people how to save water.'' To prove his point, Reynolds opens a door under his laundry tub to reveal a simple valve that costs around $160 for a plumber to install. A length of flexible hose (like those connected to washing machine outlets) can be connected to channel greywater from the laundry to water the garden. '' A greywater system may be too expensive for some people, but they can do something like this at minimal cost. We need to show people what to do, not tell them we'll do the thinking for them''.
However, I couldn’t resist posting it here since it mentions this blog. It’s a case of the media discussing this blog discussing the media (and now this blog discussing the media back again!). There must be term for this. I mean a polite term!
As always, I’d be grateful for your opinions...
When is water fit to drink?
The Canberra Times
23 April 2007
UNIVERSITY of NSW water quality scientist Dr Stuart Khan doesn't think Canberra residents are being squeamish in objecting to ACT government plans to add treated effluent to their drinking water. ''Squeamish? Definitely not, it's a natural response that's worked well for the human species in terms of evolution we know instinctively to avoid water that's contaminated. ''I accept the 'yuk factor' as an objection. People should be concerned about the quality of their drinking water,'' he says.
Khan, a senior researcher at the University of NSW centre for water and waste technology, isn't opposed to recycled water schemes. In fact, he's been one of their most articulate champions but argues they can't be touted as foolproof or without human health risks. ''Scientists can never say there's no risk with recycled water, but most risks can be effectively managed if advanced treatment processes are employed.''
Several years ago, Khan conducted the first survey of pharmaceuticals in Australia's waterways as his doctoral thesis. He looked at which drugs anti-depressants, contraceptive pills, anti-inflammatories and antibiotics were being prescribed at high enough concentrations to be detected in municipal sewage. Studying inflows and discharges at a sewage treatment plant in western Sydney, Khan found removal of these biologically active compounds was variable, depending on methods of wastewater treatment. He told the ABC's ''Earth Hour'' in 2004 that pharmaceutical drugs were entering the environment at ''pretty much the same mass per year'' as pesticides and it was time to ''look at setting, or at least talking about, arguing about, what are acceptable limits that a sewage treatment plant can emit.''
Earlier this year, he co-authored a report for the Local Government Association of Queensland on the risks and health effects of adding highly treated wastewater reclaimed from municipal effluents to drinking water. The report says the microbial and chemical quality of water intended for recycling ''is generally very high'' and risks associated with potable reuse ''while never zero, are successively decreased with increasing levels of treatment.'' But it also says the range of potential contaminants in municipal wastewaters ''is significantly greater than in well protected environmental waters'', and concentrations of these contaminants can fluctuate, making them difficult to detect by conventional water monitoring systems. ''While studies undertaken overseas bode well for the safety of recycled water generally, exactly how effectively these studies can be translated to potential Australian schemes is less clear. Water sources will differ and water treatment processes will differ,'' the report says.
In recent weeks, Khan has been keeping a close eye on political events in the ACT, posting commentary on his water recycling discussion blogsite ( www.waterrecycling.blogspot.com ). Former ACT Planning Minister Simon Corbell was stripped of the portfolio after calling for a more cautious approach to water recycling, following concerns raised by Canberra Hospital infectious diseases specialist Professor Peter Collignon over the risks of prescription drugs persisting in the waster supply. ''I'm concerned that the recent water policy is a fait accompli ... I think as a government we need to be more critical of what's being proposed,'' Corbell said. On his blog, Khan wrote: ''One might think this would be perfectly reasonable and, in fact, prudent position to take especially given Collignon's expression of concern. Absolute confidence that public health will be protected is vital ... I am perhaps idealistic enough to think that open debate should be encouraged, rather than crushed. If a Planning Minister can't engage in a public debate about water management and public safety, who can?''
During the NSW election campaign, former state Liberal leader Peter Debnam downed as glass of ''recycled'' water as part of a taste-test media stunt to launch his $955million water recycling plan. There were political red faces when it was later revealed by water experts that the water used in the taste-test came from Sydney Water's North Richmond filtration plant on the Hawkesbury-Nepean river. Sydney Water confirmed the water was produced from run-off, and was not recycled water.
Toowoomba's rejection of recycled water has been criticised as ill-informed and the result of a fear campaign exaggerating health risks. Khan was involved in the public debate as a supporter of water recycling schemes but says it's wrong to portray Toowoomba residents ''as a bunch of Luddites incapable of accepting scientific fact.'' He argues the major factor for many No- voters in Toowoomba had ''little to do with any suggestion that there may be something fundamentally wrong with the concept of planned potable water recycling.'' What scuppered the scheme was lack of community consultation and ''a perceived unwillingness'' of the council to consider alternative water management options. ''These factors left the community feeling disempowered and generated suspicion of the council's motivation,'' he writes. ''There are many lessons to be learned from Toowoomba. If we dont take them seriously, we are doomed to repeat the mistakes. Observing people in the media and on this blog lashing out at Toowoomba residents for being stupid, naive and irrational is not encouraging.''
Last week, Australian National University professor of water resources, Ian White, dismissed the ACT Government's plans to add treated effluent to Canberra's drinking water as a cynical way ''to make money by pushing up water prices.'' He also accused ACT Chief Minister Jon Stanhope of a potential conflict on interest between his new role as environment minister and his financial obligations as principal government shareholder of water utility Actew.
Stanhope dismissed the suggestion as ''extremely offensive'', saying he was fully aware of, and accepted, his ministerial responsibilities to distinguish between the dual roles. But White and former Actew chief engineer Cary Reynolds have raised questions about the cost-benefit analyses that under-pin the government's push to introduce recycled water. ''It's a very expensive option and the government haven't adequately explained why it's necessary or what it will cost consumers. Where's the economic debate? We seem to have skipped that,'' White says. He claims the government's plans to introduce recycled water ignore the recommendations of a previous Actew report in 1994 which outlined a 50 year strategy to guide Canberra's water supplies. The report, which involved two-years of community consultation, was designed to be reviewed and updated every five years with new data, but was shelved in 2004 and replaced by the government's pared-down Think Water Act Water strategy.
Reynolds was one of the authors of the 1994 report which won national awards for innovation and points out more than 97 per cent of those surveyed were in favour of using treated water to irrigate parks and gardens. Only 20 per cent supported use of treated and recycled effluent as drinking water. Reynolds believes a less costly solution to Canberra's water problems is to ''mine'' effluent from the sewer and stormwater systems, using treated effluent for irrigation.
Effluent mining is already being used to irrigate the Duntroon sports ovals, and the system could be expanded across the city at a cost of about $5million to build two treatment plants, he says. ''Do we need to go to recycled drinking water because of the drought? Probably not if we remove irrigation demands from potable water by using treated effluent, and place more emphasis on community education. We need to tell people how to save water.'' To prove his point, Reynolds opens a door under his laundry tub to reveal a simple valve that costs around $160 for a plumber to install. A length of flexible hose (like those connected to washing machine outlets) can be connected to channel greywater from the laundry to water the garden. '' A greywater system may be too expensive for some people, but they can do something like this at minimal cost. We need to show people what to do, not tell them we'll do the thinking for them''.
Wednesday, April 18, 2007
Honoured scientist toasts recycled water
A short and sweet article from The Age (Melbourne) today...
Honoured scientist toasts recycled water
The Age
Chee Chee Leung
April 18, 2007
THE former head of a committee set up by the Bracks Government to help plan Melbourne's water strategy has supported using recycled water for drinking.
Emeritus Professor Nancy Millis, a Victorian microbiologist who last night received a lifetime achievement award, said drinking recycled water could boost dwindling resources.
"This is something which people are a little bit concerned about, but I believe the technology is now very well established," said Professor Millis, who chaired Melbourne's water resources strategy committee from 2000 to 2002.
Her comments come just months after Premier Steve Bracks said recycled water would not be required under the state's 50-year plan.
Professor Millis said if low rainfall continued, policymakers should look at different ways of providing water.
Photo: Pat Scala (The Age)
The scientist, who chaired a committee overseeing gene technology for the Australian Government, also said rules covering genetic engineering should be relaxed if research revealed that risks were less severe than first thought. "You move in response to knowledge, you don't move in response to prejudice."
Professor Millis spoke to The Age yesterday before she was honoured for her lifetime achievement in science by the ATSE Clunies Ross Awards, held in Melbourne. The awards recognise people who have applied science and technology for the benefit of Australia.
Other winners this year include Professor Ian Frazer, who developed the cervical cancer vaccine, and ResMed chairman Dr Peter Farrell, for making devices to treat obstructive sleep apnoea.
Honoured scientist toasts recycled water
The Age
Chee Chee Leung
April 18, 2007
THE former head of a committee set up by the Bracks Government to help plan Melbourne's water strategy has supported using recycled water for drinking.
Emeritus Professor Nancy Millis, a Victorian microbiologist who last night received a lifetime achievement award, said drinking recycled water could boost dwindling resources.
"This is something which people are a little bit concerned about, but I believe the technology is now very well established," said Professor Millis, who chaired Melbourne's water resources strategy committee from 2000 to 2002.
Her comments come just months after Premier Steve Bracks said recycled water would not be required under the state's 50-year plan.
Professor Millis said if low rainfall continued, policymakers should look at different ways of providing water.
Photo: Pat Scala (The Age)The scientist, who chaired a committee overseeing gene technology for the Australian Government, also said rules covering genetic engineering should be relaxed if research revealed that risks were less severe than first thought. "You move in response to knowledge, you don't move in response to prejudice."
Professor Millis spoke to The Age yesterday before she was honoured for her lifetime achievement in science by the ATSE Clunies Ross Awards, held in Melbourne. The awards recognise people who have applied science and technology for the benefit of Australia.
Other winners this year include Professor Ian Frazer, who developed the cervical cancer vaccine, and ResMed chairman Dr Peter Farrell, for making devices to treat obstructive sleep apnoea.
Monday, April 16, 2007
A Message From The CSIRO
Dr Simon Toze is a Principal Research Scientist at CSIRO Land and Water. He wrote the following opinion piece that was published in today's Canberra Times. I think its a well written contribution to the current public discussion. What do you think?
Research Guides Way Forward
Simon Toze
The Canberra Times
16 April 2007
AS WE ALL know, Australia is waking up to the variability in water supply across the continent and experiencing documentable climate change. The eastern seaboard is still in the grip of the worst drought in living memory. Water levels in dams over much of the country are at critically low levels. Water is no longer taken for granted, but is now widely acknowledged as a precious resource that we need to manage.
The recycling of waste water is seriously being considered by most water utilities as one of several ways to increase their water resources and to provide a buffer against drought. Using water just once and then discarding it is now viewed as wasteful and unsustainable. Reusing water reduces the strain on our existing freshwater resources and is better for the environment.
Technology is now so advanced that waste water can be treated to a level that is better than the water coming out of our taps. But there are other options, so why recycle water? Why expose ourselves to the risks? Waste water has the advantage over other sources such as storm water in that it is available in plentiful amounts, irrespective of climatic conditions. It also has the advantage that it tends to be of a consistent quality, not necessarily a good quality, but consistent. This makes treatment easier than for a water of variable quality such as storm water. The treatment of waste water is less energy intensive than desalination as it contains about 35 times less salt than seawater.
There is a downside. Waste water can contain contaminants that could be harmful to our health. This can include all the wastes and contaminants discarded from our households, ranging from faecal matter containing bacteria and viruses through to medications excreted in our urine. Then there are the cleaning products and other chemicals used in households.
What are the real risks from these contaminants and how effective are the treatment processes? How sure are we that the water utilities can consistently provide us with a safe product? CSIRO, water utilities, universities and government departments have been undertaking research for a number of years to begin to predict the actual risk from many of these contaminants and understand the effectiveness of treatments to remove them from water. Research has also shown that conventional treatment barriers can effectively remove germs that cause illness. Similarly, the removal of heavy metals and nutrients are well documented.
A group of contaminants that has recently come to the forefront of public awareness is trace organics. These chemicals include the sex hormones oestrogen and testosterone as well as chemicals which mimic the activity of these hormones. Other trace organics receiving attention are pharmaceuticals and personal-care products such as shampoo and body cleansers. Less is known about the presence of these chemicals in waste water and the effectiveness of treatment processes to remove them. These chemicals are usually present in such low concentrations that detection is very difficult. For other chemicals it has been difficult to distinguish them from the large number of other organic compounds, some of which are naturally found in tap water. In other cases, such as newly developed medications, they have only been in use for the past few years and detection methods are yet to be developed. Conventional treatment removes many of these chemicals from waste water or reduces them to levels at the limit of detection. In fact, many researchers are now coming to the opinion that their very low concentrations in treated waste water do not pose a human health hazard.
In order to better understand the environmental risks of these compounds, research is being undertaken to assemble better data on the effect of these compounds on native animals in our water ways. The ability of advanced treatment systems to completely strip these trace organics from recycled water is also being closely examined to ensure that humans and the environment are protected. This is especially important as Australian governments and cities move toward the concept of treating recycled water for drinking purposes.
Research efforts to date have also led to the development of new guidelines for recycling water. The new Australian Guidelines for Water Recycling use an internationally accepted risk-management approach, and are currently being extended to address recycling for drinking water. The guidelines recommend that in the design of water reuse schemes there are a number of fail-safe barriers which ensure treatment effectiveness. This means that if one treatment barrier fails, another is able to cope. Control points which alert if a failure occurs are also required, and in many cases are able to shut down delivery immediately a failure is detected in the plant.
This then leads us to the ultimate question. Is it safe for Australians to drink recycled water? The short answer is that with appropriate treatment and safeguards the water is as safe as our current water supplies. Any researcher working on water recycling will admit there is much still to learn. We do know already that the risks are very low, and are probably less than those associated with drinking water already flowing from our taps. Other places such as California, Belgium, Singapore and Namibia are already recycling water for drinking and despite extensive epidemiological studies no detrimental health impacts have been detected. The Australian public can be reassured that government agencies, researchers from CSIRO and universities, and water utilities are not blindly leaping into recycling for drinking purposes but are taking measured, educated steps using sound research to guide developments and the next course of action.
And do researchers like me put our money where our mouth is? Indeed. I have drunk recycled water, and given it to my five year old, and felt perfectly confident in doing so.
Dr Toze is principal research scientist at CSIRO Land and Water.
Research Guides Way Forward
Simon Toze
The Canberra Times
16 April 2007
AS WE ALL know, Australia is waking up to the variability in water supply across the continent and experiencing documentable climate change. The eastern seaboard is still in the grip of the worst drought in living memory. Water levels in dams over much of the country are at critically low levels. Water is no longer taken for granted, but is now widely acknowledged as a precious resource that we need to manage.
The recycling of waste water is seriously being considered by most water utilities as one of several ways to increase their water resources and to provide a buffer against drought. Using water just once and then discarding it is now viewed as wasteful and unsustainable. Reusing water reduces the strain on our existing freshwater resources and is better for the environment.
Technology is now so advanced that waste water can be treated to a level that is better than the water coming out of our taps. But there are other options, so why recycle water? Why expose ourselves to the risks? Waste water has the advantage over other sources such as storm water in that it is available in plentiful amounts, irrespective of climatic conditions. It also has the advantage that it tends to be of a consistent quality, not necessarily a good quality, but consistent. This makes treatment easier than for a water of variable quality such as storm water. The treatment of waste water is less energy intensive than desalination as it contains about 35 times less salt than seawater.
There is a downside. Waste water can contain contaminants that could be harmful to our health. This can include all the wastes and contaminants discarded from our households, ranging from faecal matter containing bacteria and viruses through to medications excreted in our urine. Then there are the cleaning products and other chemicals used in households.
What are the real risks from these contaminants and how effective are the treatment processes? How sure are we that the water utilities can consistently provide us with a safe product? CSIRO, water utilities, universities and government departments have been undertaking research for a number of years to begin to predict the actual risk from many of these contaminants and understand the effectiveness of treatments to remove them from water. Research has also shown that conventional treatment barriers can effectively remove germs that cause illness. Similarly, the removal of heavy metals and nutrients are well documented.
A group of contaminants that has recently come to the forefront of public awareness is trace organics. These chemicals include the sex hormones oestrogen and testosterone as well as chemicals which mimic the activity of these hormones. Other trace organics receiving attention are pharmaceuticals and personal-care products such as shampoo and body cleansers. Less is known about the presence of these chemicals in waste water and the effectiveness of treatment processes to remove them. These chemicals are usually present in such low concentrations that detection is very difficult. For other chemicals it has been difficult to distinguish them from the large number of other organic compounds, some of which are naturally found in tap water. In other cases, such as newly developed medications, they have only been in use for the past few years and detection methods are yet to be developed. Conventional treatment removes many of these chemicals from waste water or reduces them to levels at the limit of detection. In fact, many researchers are now coming to the opinion that their very low concentrations in treated waste water do not pose a human health hazard.
In order to better understand the environmental risks of these compounds, research is being undertaken to assemble better data on the effect of these compounds on native animals in our water ways. The ability of advanced treatment systems to completely strip these trace organics from recycled water is also being closely examined to ensure that humans and the environment are protected. This is especially important as Australian governments and cities move toward the concept of treating recycled water for drinking purposes.
Research efforts to date have also led to the development of new guidelines for recycling water. The new Australian Guidelines for Water Recycling use an internationally accepted risk-management approach, and are currently being extended to address recycling for drinking water. The guidelines recommend that in the design of water reuse schemes there are a number of fail-safe barriers which ensure treatment effectiveness. This means that if one treatment barrier fails, another is able to cope. Control points which alert if a failure occurs are also required, and in many cases are able to shut down delivery immediately a failure is detected in the plant.
This then leads us to the ultimate question. Is it safe for Australians to drink recycled water? The short answer is that with appropriate treatment and safeguards the water is as safe as our current water supplies. Any researcher working on water recycling will admit there is much still to learn. We do know already that the risks are very low, and are probably less than those associated with drinking water already flowing from our taps. Other places such as California, Belgium, Singapore and Namibia are already recycling water for drinking and despite extensive epidemiological studies no detrimental health impacts have been detected. The Australian public can be reassured that government agencies, researchers from CSIRO and universities, and water utilities are not blindly leaping into recycling for drinking purposes but are taking measured, educated steps using sound research to guide developments and the next course of action.
And do researchers like me put our money where our mouth is? Indeed. I have drunk recycled water, and given it to my five year old, and felt perfectly confident in doing so.
Dr Toze is principal research scientist at CSIRO Land and Water.
Saturday, April 14, 2007
Party Politics in the ACT
As we discussed a couple of weeks ago, the ACT Labor government is currently considering the possibility of developing an indirect potable water recycling scheme for Canberra. The proposal has been championed by ACT Chief Minister Jon Stanhope, who also happens to have the role of Water Minister.
The proposal had also received support from the Liberals and Greens, and thus it seemed unlikely to be the subject of a significant political scuffle.
However, in a surprise move this week, the ACT Attorney General, Simon Corbell, broke the apparent cardinal rule against breaching cabinet confidentiality and solidarity. Corbell’s ‘crime’ was simply to call publicly for more caution:
“I've realised there's a need for a more sceptical approach...I'm concerned that the recent water policy is a fait accompli...I think as a Government we do need to be more critical of what's being proposed...I am calling for more caution.”
The Canberra Times reported that Corbell “cited health concerns raised by Canberra Hospital infectious diseases physician Peter Collignon about drinking recycled sewage” and that he “called for a fresh Government inquiry into the issue, focusing on the risks of prescription drugs persisting in the water supply”.
One might think that this would be a perfectly reasonable and, in fact, prudent position to take, -especially given Collignon’s expression of concern. Absolute confidence that public health will be protected is vital for all planned (and unplanned!) indirect potable recycling schemes. If there is a lack of such confidence in the community, especially among decision makers, it needs to be addressed. If a lack of adequate caution is revealed, it must be corrected before any significant progress is made.
However, the response from Corbell’s ALP Party colleagues came fast and furious. The Minister for Territory and Municipal Services, John Hargreaves hit the roof, as reported by the Canberra Times:
Mr Hargreaves, said if Mr Corbell could not hold to the party line he should do "the honourable thing" and resign from cabinet. "His expression of disloyalty to the Chief Minister in recent times is unforgivable," Mr Hargreaves said. "I am seriously disappointed that the hitherto strong cabinet solidarity ... has been abused. I will not stand by and be silent when the integrity and leadership of Jon Stanhope is in question." Mr Hargreaves warned Mr Corbell any leadership aspirations he had were now crushed. "As long as the right wing [of the ALP] draws breath and I'm in the Parliament he will not be in the leadership or deputy leadership," he said.
Mr Hargreaves said ministers should raise such concerns in cabinet and then abide by cabinet's collective decision. "That was a complete and absolute breach of cabinet confidentiality and solidarity," he said of Mr Corbell's remarks. "It was a deliberate incursion into the portfolio responsibilities of the Chief Minister."
Corbell’s punishment was revealed today when it was reported that Stanhope had stripped Corbell of “his favourite” ministerial portfolio, Planning, which he had held for almost a decade.
However, it seems that not all ACT Labor members are quite so rash. Speaker Wayne Berry, responded saying "What Simon said in relation to water was sound judgment and it will widen the debate,".
I’m not naïve enough to not realise that ALP factional manoeuvring is at least partially to explain for this week’s ruckus. However, I am perhaps idealistic enough to think that open debate should be encouraged, rather than crushed. If a Planning Minister can’t engage in a public debate about water management and public safety, who can?
Clearly the loyal Mr Hargreaves was concerned about the message that Corbell’s comments would send to the community. But frankly, I think most people will be more concerned about the clear priority in which political solidarity has been placed above open dialogue about a controversial proposal and a stated need for caution.
Would it be unreasonable to expect that sustainable water management and protection of public health should be above party politics? Don’t answer that.
Perhaps the title of this post should have been ‘Party Politics (Caught) in the ACT’.
The proposal had also received support from the Liberals and Greens, and thus it seemed unlikely to be the subject of a significant political scuffle.
However, in a surprise move this week, the ACT Attorney General, Simon Corbell, broke the apparent cardinal rule against breaching cabinet confidentiality and solidarity. Corbell’s ‘crime’ was simply to call publicly for more caution:
“I've realised there's a need for a more sceptical approach...I'm concerned that the recent water policy is a fait accompli...I think as a Government we do need to be more critical of what's being proposed...I am calling for more caution.”
The Canberra Times reported that Corbell “cited health concerns raised by Canberra Hospital infectious diseases physician Peter Collignon about drinking recycled sewage” and that he “called for a fresh Government inquiry into the issue, focusing on the risks of prescription drugs persisting in the water supply”.
One might think that this would be a perfectly reasonable and, in fact, prudent position to take, -especially given Collignon’s expression of concern. Absolute confidence that public health will be protected is vital for all planned (and unplanned!) indirect potable recycling schemes. If there is a lack of such confidence in the community, especially among decision makers, it needs to be addressed. If a lack of adequate caution is revealed, it must be corrected before any significant progress is made.
However, the response from Corbell’s ALP Party colleagues came fast and furious. The Minister for Territory and Municipal Services, John Hargreaves hit the roof, as reported by the Canberra Times:
Mr Hargreaves, said if Mr Corbell could not hold to the party line he should do "the honourable thing" and resign from cabinet. "His expression of disloyalty to the Chief Minister in recent times is unforgivable," Mr Hargreaves said. "I am seriously disappointed that the hitherto strong cabinet solidarity ... has been abused. I will not stand by and be silent when the integrity and leadership of Jon Stanhope is in question." Mr Hargreaves warned Mr Corbell any leadership aspirations he had were now crushed. "As long as the right wing [of the ALP] draws breath and I'm in the Parliament he will not be in the leadership or deputy leadership," he said.
Mr Hargreaves said ministers should raise such concerns in cabinet and then abide by cabinet's collective decision. "That was a complete and absolute breach of cabinet confidentiality and solidarity," he said of Mr Corbell's remarks. "It was a deliberate incursion into the portfolio responsibilities of the Chief Minister."
Corbell’s punishment was revealed today when it was reported that Stanhope had stripped Corbell of “his favourite” ministerial portfolio, Planning, which he had held for almost a decade.
However, it seems that not all ACT Labor members are quite so rash. Speaker Wayne Berry, responded saying "What Simon said in relation to water was sound judgment and it will widen the debate,".
I’m not naïve enough to not realise that ALP factional manoeuvring is at least partially to explain for this week’s ruckus. However, I am perhaps idealistic enough to think that open debate should be encouraged, rather than crushed. If a Planning Minister can’t engage in a public debate about water management and public safety, who can?
Clearly the loyal Mr Hargreaves was concerned about the message that Corbell’s comments would send to the community. But frankly, I think most people will be more concerned about the clear priority in which political solidarity has been placed above open dialogue about a controversial proposal and a stated need for caution.
Would it be unreasonable to expect that sustainable water management and protection of public health should be above party politics? Don’t answer that.
Perhaps the title of this post should have been ‘Party Politics (Caught) in the ACT’.
Monday, April 09, 2007
Planned Indirect Potable Reuse in Belgium
Belgium has a relatively new planned indirect potable recycling scheme which is not well known in Australia. For this reason, I thought it might be interesting to take a quick look at it.
The northern region of Belgium is known as Flanders and like most of Belgium, Flanders relies heavily on groundwater extraction for potable water supplies. Flanders is among the most densely populated areas of Europe. It is highly industrialised and is also home to much intensive agriculture. These factors have led to severe over-extraction of many important aquifers.
In 1990, the Flemish government established the water utility company ‘Aquafin’ to establish and operate advanced sewage treatment infrastructure in Flanders. Aquafin now operates more than 200 sewage treatment plants (STPs) and the effluents from several of these are reused for industrial applications, -most commonly as industrial cooling waters.
The Intermunicipal Water Company of the Veurne Region (IWVA) is responsible for the production and distribution of drinking-water in the western part of the Flemish coastal plain. In the early 1990s, it became apparent that the IWVA could no-longer continue to increase the groundwater extraction from its dune aquifer catchments of St. Andre and the Westhoek to fulfil the growing potable water demand. Groundwater recharge of the unconfined aquifer of the St. Andre catchment was identified as the optimum solution. Treated effluent from Aquafin’s nearby Wulpen STP was selected as the source for the production of water to recharge the aquifer.
IWVA constructed the Torreele advanced water treatment plant adjacent to the Wulpen STP, with a production capacity of 2,500 megalitres (2.5 billion litres) per year, -equivalent to around 40% of the local potable water demand. The Torreele treatment scheme is shown below (click to enlarge).
Secondary effluent from the Wulpen STP is pre-screened with mechanical screens before chlorination and retention in an equalisation basin. It is then treated by ultrafiltration (UF) membranes before further chlorine treatment and then reverse osmosis (RO) membrane treatment. Finally, the water is subjected to ultraviolet (UV) radiation. The advanced-treated reclaimed water is discharged to a 70 cm deep, 1.8 hectare pond for infiltration to the groundwater aquifer.
After a residence time of at least 40 days, the water is extracted from the aquifer from 112 wells located at various distances (around 40 to 100 m) from the infiltration pond.
The UF and RO membrane concentrate streams are discharged into a nearby brackish water canal that flows 7 kilometres to the sea. Since 2003, tests have been performed on the concentrate using a constructed wetland to successfully reduce nitrogen, suspended solids and, to a lesser extent, organics in the concentrate.
Since the groundwater recharge began in 2002, there has been a gradual increase in the groundwater levels in the aquifer, providing a valuable protection against saline water intrusion from the North Sea.
The Torreele/Wulpen project was recently profiled in the weekly international newsletter ‘Water Desalination Report’ (2 April 2007, Vol 43, No 13). The editor of the Report included the comment:
“As this newspaper recently noted: just because it isn’t called reuse, doesn’t mean it isn’t reuse. Virtually every potable water supply in Europe is, to some extent, an example of ‘unplanned’ indirect potable reuse. But the Torreele/Wulpen project is the most honest example where the local community has been well informed that the water supply has been reclaimed”.
I don’t have any actual information regarding just how informed the community is or what the community response was. However, I would be very keen to find out. So if you can find any information –perhaps on the internet or any local contacts-, I would be most interested to hear of it.
Thanks to Davide Bixio at Aquafin for supplying most of the information (and the image) presented here.
The northern region of Belgium is known as Flanders and like most of Belgium, Flanders relies heavily on groundwater extraction for potable water supplies. Flanders is among the most densely populated areas of Europe. It is highly industrialised and is also home to much intensive agriculture. These factors have led to severe over-extraction of many important aquifers.
In 1990, the Flemish government established the water utility company ‘Aquafin’ to establish and operate advanced sewage treatment infrastructure in Flanders. Aquafin now operates more than 200 sewage treatment plants (STPs) and the effluents from several of these are reused for industrial applications, -most commonly as industrial cooling waters.
The Intermunicipal Water Company of the Veurne Region (IWVA) is responsible for the production and distribution of drinking-water in the western part of the Flemish coastal plain. In the early 1990s, it became apparent that the IWVA could no-longer continue to increase the groundwater extraction from its dune aquifer catchments of St. Andre and the Westhoek to fulfil the growing potable water demand. Groundwater recharge of the unconfined aquifer of the St. Andre catchment was identified as the optimum solution. Treated effluent from Aquafin’s nearby Wulpen STP was selected as the source for the production of water to recharge the aquifer.
IWVA constructed the Torreele advanced water treatment plant adjacent to the Wulpen STP, with a production capacity of 2,500 megalitres (2.5 billion litres) per year, -equivalent to around 40% of the local potable water demand. The Torreele treatment scheme is shown below (click to enlarge).
Secondary effluent from the Wulpen STP is pre-screened with mechanical screens before chlorination and retention in an equalisation basin. It is then treated by ultrafiltration (UF) membranes before further chlorine treatment and then reverse osmosis (RO) membrane treatment. Finally, the water is subjected to ultraviolet (UV) radiation. The advanced-treated reclaimed water is discharged to a 70 cm deep, 1.8 hectare pond for infiltration to the groundwater aquifer.
After a residence time of at least 40 days, the water is extracted from the aquifer from 112 wells located at various distances (around 40 to 100 m) from the infiltration pond.
The UF and RO membrane concentrate streams are discharged into a nearby brackish water canal that flows 7 kilometres to the sea. Since 2003, tests have been performed on the concentrate using a constructed wetland to successfully reduce nitrogen, suspended solids and, to a lesser extent, organics in the concentrate.
Since the groundwater recharge began in 2002, there has been a gradual increase in the groundwater levels in the aquifer, providing a valuable protection against saline water intrusion from the North Sea.
The Torreele/Wulpen project was recently profiled in the weekly international newsletter ‘Water Desalination Report’ (2 April 2007, Vol 43, No 13). The editor of the Report included the comment:
“As this newspaper recently noted: just because it isn’t called reuse, doesn’t mean it isn’t reuse. Virtually every potable water supply in Europe is, to some extent, an example of ‘unplanned’ indirect potable reuse. But the Torreele/Wulpen project is the most honest example where the local community has been well informed that the water supply has been reclaimed”.
I don’t have any actual information regarding just how informed the community is or what the community response was. However, I would be very keen to find out. So if you can find any information –perhaps on the internet or any local contacts-, I would be most interested to hear of it.
Thanks to Davide Bixio at Aquafin for supplying most of the information (and the image) presented here.
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