Sunday, February 04, 2007

Think before you agree to drink

This week Snow Manners and John Dowson of Toowoomba published a booklet titled ‘Think Before you Agree to Drink – Is Sewage a Source of Drinking Water?’. I thought it might be appropriate to provide a brief response from my own perspective.

Manners and Dowson have an important role to play in the current community debate regarding the use of recycled water. I see their booklet as a sincere effort to stimulate community discussion and probe some important questions. While I certainly don’t agree with all of their claims, I contend that Manners and Dowson should be commended for having lifted the debate beyond childish sloganeering and purely emotional appeals to the ‘yuck factor’.

Manners and Dowson are clearly unimpressed with scientific claims that advanced treated recycled water can be (and is) safely provided to millions of consumers without negative consequence. In particular, they appear to be concerned about the achievable chemical quality of the water. This topic is, of course, my major interest as well and is clearly in need of further community discussion.

In general, I think Manners and Dowson have done a nice job of highlighting the important issue of endocrine disrupting chemicals (EDCs) in the environment. Some of the information presented should indeed cause people to think more carefully about the presence of chemicals in our environment generally. However, my major concern is that almost all of the information presented is done so without explanation of its original context. Context can be important for accurate interpretation of many findings and statements. The inclusion of such context-devoid statements in this booklet may leave readers with the impression that the context had something to do with advanced treated recycled water. This is unfortunate, since in many cases it did not, and is thus somewhat misleading.


Introduction

In the introduction section, Manners and Dowson state that “Many who promote recycling sewage water for drinking cite global warming and the environment as the moral force behind their push”. My own observation of proponents of recycling is that they are concerned about ensuring communities have adequate high quality water to drink and use for other purposes. Manners and Dowson’s statement appears to be pitched to sceptics of global warming, but whether dwindling drinking water supplies are the result of global warming, natural drought cycles, population growth, or poor management is irrelevant. The only reasonable point of view is that potable water shortages need to be addressed regardless of their cause. For those in a position of being able to achieve this, their obligation to do so may well be described as a “moral force”.

Manners and Dowson contend that recycling proponents “have failed to give any firm assurances as to the safety of the idea and its long term effects on humans”. However, the Local Government Association of Queensland has commissioned and published a report (co-authored by myself) demonstrating that sewage effluents subjected to advanced water treatment in preparation for recycling are routinely of equal or better quality than traditional water sources. Exactly the same safety assurances that are provided for traditional drinking water supplies can be (and are) given for advanced recycled water supplies. To demand more is, in my opinion, unreasonable.

The statement that “many who support and promote recycling of sewage water for drinking, including scientific people, appear not to mention drugs and more particularly chemicals that are and maybe in sewage water” is intriguing. First, it is important to recognise that "drugs" are "chemicals". Sewage is a complex cocktail of chemicals, many of which are considerably more toxic than most drugs. In my experience, when scientists talk about the chemical constitution of sewage, drugs have been routinely mentioned during the last decade (I even wrote a PhD thesis on the topic). However, none of these scientists are advocating drinking sewage. Advanced treated recycled water has no chemical resemblance to sewage and I am fairly confident that Manners and Dowson are actually aware of this somewhat unsubtle point.

Water Quality Rating of Sewage Water


Manners and Dowson take issue with the Australian Water Association’s “Six Star Rating System”. However, they appear to have misinterpreted its purpose. The star rating system is not intended to be a scientific comprehensive description of water quality or risk. It is a communication tool to be used to describe water that has been subjected to various subsequent treatment steps. Similar star rating systems are used to describe energy efficiency for white goods. The energy rating system allows consumers to make quick comparisons without requiring a detailed understanding of power consumption or thermodynamics. Similarly the water rating system is intended to allow consumers to compare water qualities without requiring an intricate knowledge of water treatment and chemistry. To try to read more into the star rating system than is intended, is inappropriate and bound to lead to the frustrations evidently experienced by Manners and Dowson.

Its Done All Over the World – Or Is It?

While this booklet in general has some useful information to help inform debate, it is unfortunate that this section seems particularly poorly researched. In addition to the water recycling schemes mentioned by Manners and Dowson, a little more research may have revealed some more enlightening examples.

The statement that “there is no community on this planet that deliberately sources any significant proportion of its urban water supply from a sewage treatment plant” is wildly misleading. Apart from Windhoek in Namibia, communities source their water predominantly from underground aquifers, reservoirs (dams) and rivers; not from sewage treatment plants. However, there are many communities that intentionally replenish their aquifers, reservoirs and rivers with treated effluent. This is what was proposed in Manners and Dowson’s home city of Toowoomba and is currently planned in South East Queensland.

One example is Fairfax County, Virginia (adjacent to Washington DC) in the USA. A significant portion of that city’s drinking water supply comes from the Occoquan Reservoir in Northern Virginia. By the end of the 1960s, at least 11 conventional secondary sewage treatment plants were discharging into waterways that fed the reservoir. In 1968, the Virginia State Water Control Board commissioned a study of the reservoir with the aim of developing a detailed management plan. At that point, they instituted a policy of advanced wastewater treatment and water quality management in the Occoquan catchment. This policy mandated the construction of an advanced water reclamation plant to replace the 11 secondary treatment plants. The Upper Occoquan Sewage Authority (UOSA) was created to meet this water reclamation mandate. The water reclamation plant was completed in 1978 and since then has been expanded from an initial capacity of 57million litres per day to 200 million litres per day. The reservoir is a source of water supply for more than one million people located in the vicinity of Washington DC. UOSA has demonstrated that the advanced treated plant effluent is far cleaner than other sources of surface water which inflow into the Occoquan Reservoir.

An alternative means of recycling water in some cities is by replenishing groundwater aquifers. Prevention of seawater intrusion to aquifers is also a very important aspect of many groundwater replenishment schemes. However, the way Manners and Dowson present their information gives the incorrect impression that indirect potable reuse from schemes such as those developed in Orange County California is somehow incidental. In fact, many of these have been very carefully planned indirect potable reuse schemes. This is how the USA Environment Protection Agency (EPA) put it in a 1998 water recycling brochure: “Although most water recycling projects have been developed to meet nonpotable water demands, a number of projects use recycled water indirectly for potable purposes. These projects include recharging ground water aquifers and augmenting surface water reservoirs with recycled water. In ground water recharge projects, recycled water can be spread or injected into ground water aquifers to augment ground water supplies, and to prevent salt water intrusion in coastal areas. For example, since 1976, the Water Factory 21 Direct Injection Project, located in Orange County, California, has been injecting highly treated recycled water into the aquifer to prevent salt water intrusion, while augmenting the potable ground water supply.”

Planned indirect potable water recycling continues to be an important water supply strategy in the USA with new schemes currently being planned in cities such as Denver and Dallas.

So-called “unplanned” indirect potable water reuse is also extremely important and involves many cities much larger than the examples given by Manners and Dowson (Esk and Kilcoy in Queensland). A classic example is the Mississippi River which flows from North to South across the USA. Each city from Minneapolis through Memphis all the way down to New Orleans takes drinking water from the Mississippi and returns treated effluents back to it. Each city is thus drinking recycling treated effluents from cities to its north. The Ohio River is another example with many downstream cities such as Cincinnati using water that has been partially sourced from the treated effluent of upstream cities such as Pittsburgh.

In Australia, Lake Burragorang (Warragamba Dam) services Sydney and receives upstream effluents from Goulburn and Lithgow. The Nepean River (Western Sydney) services the Richmond drinking water treatment plant and receives effluents from the Penrith sewage treatment plant. Sugarloaf reservoir services Melbourne and receives effluent from Olinda Creek sewage treatment plant. The Mount Crosby Weir system services Brisbane and receives effluent from Fernvale, Esk, Lowood, Toogoolawah, Gatton and Laidley. The Mount Bold reservoir services Adelaide and receives effluent from the Hahndorf sewage treatment plant. Furthermore, Adelaide draws a large part of its supplies from the Murray River, to which is discharged treated effluents from towns all along the Murray and Darling River systems including Canberra.

Chemical Concerns

Endocrine disrupting chemicals (EDCs) in the environment are recognised by almost all scientists (in relevant fields) for the effects that they have been shown to have on a variety of wildlife and may be suspected to have on humans. Manners and Dowson have done a nice job of highlighting some of the concerns regarding EDCs. However, the authors have fallen into the common trap of confusing conventionally treated sewage effluent and advanced treated recycled water.

The quote provided from John Aitken is sourced from a freelance opinion-piece published in the Financial Review after being submitted by an anti-recycling activist during the recent campaign in Toowoomba. Unfortunately, the precise chemicals that Aitken is referring to are not clear from the quote. However, I suspect that he may be referring to phthalates which are widespread in our environment. Drinking water appears to be one of the least likely exposure sources of the chemicals.

Although it remains somewhat controversial, many scientists are in agreement that there have been declines in male fertility across many parts of the world during the last fifty years. There is a diversity of opinion regarding whether chemicals in our environment may be responsible or other lifestyle factors such as exercise, diet, body weight, etc. However, very few scientists (none that I am aware of) claim any relationship between declining fertility and advanced treated recycled water.

It is necessary to recognise that Dr Sophia Dimitriadis’ report was prepared to help inform parliamentarians regarding the Australian water industry’s position and approach. It would be quite incorrect to assume the reverse. That is, that Dimitriadis’ report was actually intended to inform the industry of the position of the parliament. At the time that the report was being prepared (early 2005), there were no public plans for any planned potable water recycling scheme in Australia and the comments regarding a preference to “free up drinking water” were perfectly accurate. In fact, this still remains the generally preferred approach, but the industry and regulators have since progressed in response to the need for more substantial programs to address diminishing drinking water supplies in many cities. Although I have no study to quote, it is my general observation that the overwhelming majority of water planners, regulators and scientists in Australia now accept both the need for, and safety of, well planned and managed potable water recycling.

The “draft national guidelines for water recycling” (2005) were finalised in 2006 and are publicly available. However, as noted in the quotes selected by Manners and Dowson, these guidelines relate to treated effluents that have not been treated to a standard suitable for potable reuse. While non-potable uses of recycled water are diverse, in practice, these guidelines generally refer to secondary or tertiary treated sewage effluents used for irrigating open spaces such as golf courses. Recycled water intended for potable reuse would routinely be treated by additional advanced treatment processes specifically aimed at the removal of trace chemical contaminants. The relevant guidelines for potable water recycling are currently under development and are anticipated to be available before the end of this year.

Dr Richard Lim’s studies of mosquito fish in the Hawkesbury –Nepean River system are extremely interesting and provide further evidence of environmental impacts from sewage discharge. A number of sewage treatment plants discharge into the river system including Penrith STP and Winmalee STP. Furthermore, there are a significant number of on-site treatment systems (septic tanks) in the region, which may impact on water quality. Lim’s results are concerning and indicate that improved water treatment at the sewage treatment plant would appear to be justified.

However, once again Manners and Dowson appear to confuse sewage effluent with recycled water. The ‘unplanned’ recycled water in Richmond, referred to by Malcolm Turnbull involves important additional treatment barriers (including activated carbon treatment and chlorination) at the Richmond water treatment plant, prior to water being reticulated to customers. By not considering the drinking water treatment plant, Manners and Dowson appear to misunderstand an important aspect of water recycling as it is practised in many parts of the world.

The book “Our Stolen Future” was actually written by Theo Colborn, Dianne Dumanoski, and John Peterson Myers. Sheldon Krimsky wrote a completely unrelated book called “Hormonal Chaos”. Both books have been effective in promoting public awareness of the general issue of endocrine disrupting chemicals. Neither discusses advanced treated recycled water and neither give any indication that advanced treated recycled water is a likely source of exposure to EDCs. Both are excellent popular science books, but neither are particularly helpful in the current context.

Dr Jean Ginsberg’s letter to the editor of the Lancet is not a study of indirect potable recycling and does not attempt to compare the fertility of anybody based on the levels of recycled water consumed. Ginsberg's letter was discussed in some detail in the report recently produced by the LGAQ.

The various reports of fish being impacted by chemicals in UK rivers and streams are interesting and provide a strong argument for improved sewage treatment prior to discharge to the environment. However, as with the Hawkesbury –Nepean River system (above), Manners and Dowson seem to have again overlooked the fact that ‘unplanned’ indirect potable water recycling includes important additional barriers at the drinking water treatment plant. Planned potable water recycling (such as that proposed for South East Queensland) involves even further barriers at the advanced water treatment plant. These barriers are very effective at removing chemical contaminants and that is their purpose (among others).

The comparison between lambs fed on a diet of pellets made out of sewage sludge and the consumption of advanced treated recycled water is difficult to reconcile. Sewage sludge contains many thousands of toxic chemicals, often including heavy metals such cadmium and mercury. I’m not familiar with this study, but it doesn’t sound like a nice way to treat lambs.

I have discussed water recycling with Dr Dan Okun on numerous occasions including when I was working in his department at the University of North Carolina. It is true that Dan is not a fan of planned potable water recycling and I know a number of other people who feel the same way. Potable recycling is an undeniably controversial issue and there will always be individuals who feel that the risks outweigh the benefits. However, this is very much an ‘opinion’ and most would concede that the studies that have been undertaken demonstrate that well managed planned potable water recycling can be undertaken very safely.

The U.S. National Research Council report referred to by Manners and Dowson is widely recognised as the most comprehensive study of the viability of planned potable recycling. The study examined the safety of human health from potable recycling and concluded that “planned indirect potable reuse is a viable application of reclaimed water –but only when there is careful, thorough, project-specific assessment that includes contaminant monitoring, health and safety testing, and system reliability evaluation”. I fully concur with this finding.

The paragraph referring to Dave Schubert from the Salk Institute makes an important point about our inability to detect all possible chemicals in any water source. Advanced treatment processes such as reverse osmosis and advanced oxidation are extremely effective for removing the types of chemicals mentioned. However, chemical analysis tests are not necessarily required to confirm effective treatment. An alternative (or complimentary) approach is to use bioassays to test for the presence or absence of the toxicological effects that we are concerned about (eg. mutagenicity, estrogenicity, etc). Of course we can also test for radioactivity where that is a concern.

I will not attempt to justify or critique comments made by politicians. That would be rather pointless. We all know that they make contradictory statements and are sometimes loose with the truth. However, nothing any politician says fundamentally changes the fact that potable water recycling can be managed extremely safely.

John Poon’s comments are perfectly appropriate and reflect the dedicated approach to delivering high quality drinking water that permeates most of the Australian water industry and regulators. He is correct to raise questions regarding the longer-term health impacts from unknown contaminants and has been actively doing so for considerably longer than most. It is comforting that such people who take these issues seriously have been responsible for overseeing health risk studies as well as for the implementation of selected water treatment processes.

Professor Steven B. Oppenheimer is a veteran of a successful ‘toilet-to-tap’ campaign in Los Angeles, California. In 2001, the Los Angeles Department of Water & Power were proposing to expand an existing indirect potable water recycling scheme. The scheme was to be expanded from the Montebello Forebay area to the San Fernando Valley and environs. Tertiary-treated effluent was to be pumped to spreading fields from where it would percolate down into the drinking water aquifer. The scheme did not include reverse osmosis or advanced oxidation treatment. Furthermore, there was widespread concern that the area around the spreading fields was polluted with highly toxic industrial chemicals.

Professor Oppenheimer is an eminent researcher and perfectly qualified to be concerned about the health effects of chemicals in water. However, his concerns should be interpreted in the context of the Los Angeles scheme that he was actively campaigning against. I am unsure whether he would apply the same position to a well managed scheme incorporating advanced water treatment processes (but lets presume that he would!). My main concern is that the quotes attributed to Oppenheimer by Manners and Dowson misrepresent the findings of two important water recycling studies.

As described previously, the US National Research Council report does not warn against indirect potable reuse. On the contrary, it concludes that “planned indirect potable reuse is a viable application of reclaimed water –but only when there is careful, thorough, project-specific assessment that includes contaminant monitoring, health and safety testing, and system reliability evaluation”. The study does not say that it is “highly likely that some compounds would get through, highly likely that those compounds would be toxic and highly likely that nobody would know about it because there were no tests available”. If Manners and Dowson could identify the section of the NRC report that is apparently being paraphrased here, I would be happy to discuss Dr Oppenheimer’s interpretation further.

Oppenheimer argues that the scientists who undertook the Rand Corporation study misinterpreted their own results. He is entitled to do so. The abstract published with the study is as follows:

Groundwater Recharge with Reclaimed Water: An Epidemiologic Assessment in Los Angeles County, 1987-1991. E. M. Sloss, S. A. Geschwind, D. McCaffrey, B. R. Ritz. 1996.
“An assessment of the effects on human health of reclaimed water. The assessment compares health data on cancer incidence, mortality, and cases of infectious disease in the Montebello Forebay area, which has received some reclaimed water in its water supply for almost 30 years, with a control area that received no reclaimed water. The epidemiologic study took an ecologic approach, in which the unit of analysis is a group of people, not an individual. The results of the study do not provide evidence that reclaimed water has an adverse effect on health.”


Manners and Dowson are correct to note that the NRC report points out that normal drinking water standards were not prepared with potable water recycling in mind and thus may not be the best standard for testing its quality. I fully concur with this point and expect to see more broadly targeted assessment approaches in place for Australian schemes (as have been adopted in the USA and Singapore).

This section of the booklet has been neatly concluded by a reference to the 2005 Prague Declaration on Endocrine Disruption. This should leave all readers in no doubt that the issues of EDCs in our environment are considered to be of significant concern to scientists working in relevant environmental and toxicological fields throughout the world. A full list of the signatories to the Declaration is helpfully provided in Appendix A of the booklet. Many eminent and highly respected scientists are included. Manners and Dowson should be congratulated for helping to bring this important issue to the attention of the wider community. However, in the context of advanced water recycling, it may have been helpful to include some references to the literature demonstrating the effectiveness of advanced treatment processes for the removal of EDCs from water. This is an unfortunate oversight.

22 Issues and Questions

Manners and Dowson have raised a number of highly thought-provoking issues and questions. This list is a very valuable contribution to the ongoing debate and will be useful to facilitate wider community discussion.

I wont attempt to address any of these issues or questions here. However, some of them offer excellent topics for future blog posts. There is always plenty more to discuss!

Congratulations on a good job, Snow and John!

22 comments:

Anonymous said...

When scientists with more qualifications than you tell us not to use recycled sewage water in our drinking supplies, I think I am concerned.
When politicians tell us "drink this or die" and then go on to tell us that we have enough bores to sustain indefinitely, one has to be very worried as to whose agenda is being pushed.

I say follow the money trail and stop and think about it!

njta said...

Well done Stuart! This is a very good appraisal of the document put forward.

Essentially it is a document with many shortfalls, full of open ended statements, most of which are taken out of context.

No where is it stated of research and studies done which indicate that product water from AWT plants allows toxins through, 100% of the time, and in doses which are harmful to health.

All it has presented is the odd quote, much of the time on issues unrelated to the quality and safety of AWT plant water, and the results of studies on the health of waterways not subjected to AWT plant effluent.

Perhaps if the STPs along the Thames river had AWT plants at the back end, with the product water discharging, then the fertility problems downstream may not exist.

If this document represents the best efforts of those who oppose adopting a strategy of IPR, then it is a pretty poor effort, and very misleading.

It undoubtly will convince the gullible. But if it has been distributed as widely as claimed, I do not think the authors have done themselves any favours. A keen investigative journalist, or a savvy memeber of a large local council will be able to find fault with the document.

It will be interesting to see how and if public critics will be made in the press.

But well done to you Stuart, for at least bringing the contents into perspective.

Anonymous said...

I think Dimitriadis report was 2005 not 1995 as you say.

Stuart Khan said...

Thanks for the feedback NJTA, George and both Anonymii (or is that Anonymice?). I have now corrected the date for Dimitriadis’ report.

Anonymous said...

Give up George.

Now that it has been shown Toowoomba has adequate groundwater to meet its Drought Management Plan (ie won't run out of water) you start your pathetic scare campaigning again.

Get a life.

Anonymous said...

Mayor Thorley and Mr Kevin Flanan (Toowoomba engineer) were the people who stated quite clearly that we have enough bore water to sustain us for the future.

They have always had this water available to Toowoomba , so now we had the scare campaign trying to convince the people that the bores are salty.

Toowoomba sits on the fractured basalt and it is recharged every time it storms and we get one most weeks.
They used to say "what if it never rains again!" and every-one who has a tank knows their "little dam" fills every time it rains.

We will being drawing from the GAB and as the Mayor stated we can drop another one down if need be.

Anonymous said...

George, what dose the Lockyer Valley have to do with Toowoomba. We will be drawing from water in the fractured basalt under us and the GAB.

Stuart Khan said...

I notice that the hard copy version of the booklet has a couple of extra sections at the front which are not included in the electronic version. These are a short introduction on the outcome of the poll in Toowoomba, a discussion on why potable water recycling (or “sewage water for drinking”) is being promoted, a discussion on the media involvement in the Toowoomba debate, and a discussion on whether ‘sewage water’ is a more appropriate term than ‘recycled water’. Since I did not have access to these sections when writing the above review, they are not included in it. Apologies for any confusion.

Greg said...

george, perhaps you could tell us how recycling effluent back into our dams is going to help as get throught this drought since you seem to be of the oppinion that our aquifers will not suffice! Perhaps you believe that we can put back 100% of what we use. Even if that were the case, which it is not, you would have to consider evaporation at our dams and water loss through the AWT process and then consider that a lot of people are now using there greywater for garden use and are switching to water saving toilets and so you don't have a lot of water there either to recycle! Don't let them fool you, this is a not a solution, it is a money grabbing exercise and if the drought continues it will not help and they all know it!

Unknown said...

I noted a difference between a print copy and the on-line copy.

Apparently the online copy is the final draft for wider distribution and the prior copy which had more 'Toowoomba' paragraphs will distribute through Toowoomba, Goulburn and a few thousand for meetings.

My intrepid information sources tell me you probably have a copy that was to be handed out at the Goulburn meeting, you attended, but the Mayor disallowed distribution of opposing viewpoints from that to be presented by the government authorised "education" program.

Such is the nature of this debate.

Unknown said...

George,
I see your point of view clearly now you offer explanation more clearly. You are not connected to Toowoomba water so the issue of drinking recycled water is not your point.

You have the common concern about the competition between city and farmer for groundwater - and quite rightly.

The Gowrie farmers were against recycling for the same reason - they use the STP outflows for irrigation and have done so for years. To recycle that outflow back to the city would have dried up Gowrie Creek.

I believe that the compromise solution is to use recycled water for industry and agriculture.

The proposal to bring recycled water from Brisbane through the Lockyer and on to the Downs for agriculture thus freeing up groundwater for towns has merit and that is where you should devote your energy.

Gatton town got off the groundwater by connecting to Wivenhoe (and that pipe goes throught to Withcott) but having said that the Lockyer groundwater is in trouble but not because of urban dwellers drawing on it.

Greg said...

We do not even know of the state of the creeks and rivers running into our dams unless we take a look ourselves. I know it is dry but I have seen water flowing in the creeks around Crows Nest (last month) but none of that water seemed to make it even as far as Crows Nest Falls. Are our government and local councils making sure that none of this water is being illegally sucked out of our waterways or are they just content to tell us that any rain we get has no impact on our dams so that they can force drinking recyled effluent upon us! It is what we do not know that makes us suspicuous!

Stuart Khan said...

Hello W.F.,

Thanks for clarifying this…I figured one of the versions must have been an earlier draft, but wasn’t sure which was which. It seems that I have reviewed the appropriate version, then.

I am pleased to see that you are reliably informed of my movements. If I ever go missing, your information sources may prove invaluable.

Actually, you will be pleased to know that the booklet was freely and politely handed out after the meeting. You will also be pleased to learn that every person present was given ample opportunity to speak and ask questions of the panel. As far as I know, there were no arrests for possession of illicit information or points of view.

Unknown said...

:-)

Anonymous said...

Stuart Why did the Goulburn people ring the Toowoomba people to tell them that the book was banned and could not be handed out?
I wonder why you were sitting in the audience and not up on the stage as you are one peddling this idea too.
Are you simply trying to get some inside info and deceiving these people?

Anonymous said...

Apology Stuart, I have now found out that the book was handed out out side the meeting as you said.

Why would a Council ban it at the meeting is the interesting point.
It will get to all of Goulburn anyway and it has peaked there interest.

It also seems that you were sitting in the audience just so that you could take info back to your pal Dr Lesley .

I suppose all's fair in love and war.

What's that old saying "keep you friends close and your enemies closer"

Stuart Khan said...

Hello Anonymous,

Thanks for the polite questions. Not that I really feel that I need to explain myself to a nameless, faceless comment in cyberspace…but anyway…

I received a telephone call from a member of the Goulburn community, asking me if I would come along to the meeting. The original request/suggestion was to ask if I could have a place at the table as a potential source of information. I explained that I didn’t really want such a role in the Goulburn debate (and am unconvinced that I would have much to offer). However, I agreed to come along to the meeting for a couple of reasons.

One is that I am genuinely interested in the process of communities planning for water management, particularly when there are contentious issues involved. I have learned that there are constructive and destructive ways of going about things.

A second reason is that I agreed with the person who contacted me that possibly, I may be able to provide some constructive interpretation of what was presented at the meeting. I’m not sure that my contribution was anything great (since the whole public meeting was very straight forward with no startling claims coming from any direction). But I think our discussion afterwards was worthwhile.

I reject your suggestion regarding friends and enemies. I met a bunch of very friendly, very normal people. One of the first things one bloke said to me was to assure me that ‘its okay, you’re not on enemy territory here’, not that I ever felt that I was.

I brought a copy of the Goulburn Water Group’s plan home with me and I can say that I found it to be an intelligent document with perfectly realistic proposals. I did happen to discuss parts of it with my ‘pal Dr Leslie’ and he happened to enthusiastically agree with some aspects of the proposals.

The fact is, I’m not ‘peddling’ anything, especially in small inland towns like Goulburn (I admit that I have some strong feelings about what large coastal cities like Sydney should be doing). I would very much like to see Goulburn come up with satisfactory solutions to its current severe water shortages and I would like them to be solutions that are sustainable and that the community is comfortable with. If Goulburn is considering water recycling (potable or otherwise), I can provide some technical advice regarding scheme management and safety. However, I have no interest in trying to convince the city to adopt an indirect potable water recycling scheme.

Stuart Khan said...

Scientists slam recycled water claim
Ninemsn.com.au
Wednesday Mar 21 20:00 AEDT

Scientists whose work has been used in a booklet which claims recycled water can kill, cause infertility and change the sex of fish say they are annoyed their work has been taken out of context.

About 400,000 copies of the booklet are being distributed across Brisbane by campaigners who oppose a Queensland government plan to use purified, recycled effluent as drinking water by the end of next year.

Campaign spokesman and Toowoomba councillor Snow Manners said information provided in the booklet provided "the other side" of the debate which was being skewed by a "one-sided presentation" by the government.

Among the booklet's claims are that recycled water can kill people, alter behaviour, reduce sperm counts, cause infertility among couples and trigger a doubling in liver cancer rates.

The booklet, Think before you agree to drink - Is sewage a source of drinking water?, also claims recycled water created "gender bender" fish and made male lambs "start behaving like females".

But the scientists expressed surprise that their research had been used to back up such claims.

University of Queensland Professor of Developmental Biology Professor Peter Koopman, who is quoted in the book, said his research had been taken out of context and he had been unaware his name appeared in the booklet until told by journalists.

The book says Prof Koopman's work shows recycled water could lead to a rise in infertility rates.

"It's very intriguing," Professor Koopman told ABC radio.

"I was interviewed some time ago about the subject of increasing rates of infertility but the connection with recycled water was not apparent and it still isn't apparent to me.

"We haven't had recycled water and therefore the drop in fertility can have nothing to do with recycled water."

He said no research whatsoever had been done linking the use of recycled water to dropping infertility rates.

Acting Premier Anna Bligh said the scientific misinformation was "further evidence that this material is mischief making".

"It has very, very little relationship if any to science," she said.

"If Snow Manners has got $300,000 or $400,000 to pour down the drain that's his business, but I don't think that the people of south-east Queensland will be swayed by this sort of scaremongering."

Recycled water is used for drinking in many advanced countries, without any evidence of harmful effects.

Michael said...

Stuart,

Do you believe that all the 7 barriers we are providing is going a bit overboard, surely we could drop the advanced oxidation step? Also, do you know where I might find information on how introducing the PRW, which is cleaner than the Brisbane River, may affect the ecology of the river? Does the natural environment provide any treatment?

Thanks,

Michael

Stuart Khan said...

Hi Michael,

Good risk management for recycled water is about having ‘multiple barriers’ that provide some degree of redundancy in case of failure or under-performance of others. It’s true that the SEQ scheme is really the “Rolls Royce” of water treatment schemes and that many places get along fine with less. Advanced oxidation was added to a couple of IPR schemes in California to eliminate some small organics such as NDMA and 1,4-dioxane. However, these chemicals are also well eliminated by exposure to sunlight (as they would have in Lake Wivenhoe). The Californian schemes did not have this benefit since the water is stored in underground aquifers.

My personal feeling is that the additional safety of a “Rolls Royce” treatment scheme is justified for SEQ given the size of the population and the fact that they can afford it. Safety must always be paramount.

No, I don’t know where you will find information on how PRW may affect the ecology of the river/lake. However, I do think this is a reasonable concern. Fish rely on many micronutrients (eg. calcium and magnesium), which are removed by reverse osmosis. Some of these will be replaced during the stabilisation process, but it remains to be seen how well the various nutrients will be balanced. It’s certainly worth taking a close look at.

The natural environment does indeed provide a level of treatment. You might want to have a read through the extended discussion between ‘Mark’ and myself in the comments section here.

Stuart Khan said...

Some more press coverage for TBYATD today. This one's from The Autsralian:

Words Twisted in Anti-Recycling Propaganda
Greg Roberts
The Australian
May 21, 2007


SCIENTISTS say they have been seriously misrepresented in material prepared for a campaign to undermine the Beattie Government's recycled sewage plan.

Brisbane will become the first capital to use recycled sewage for drinking by the end of next year, with recycled water to be pumped to the Wivenhoe Dam through the $1.7 billion western corridor pipeline, the biggest project of its kind in Australia.

Opponents of the plan have vowed to stop it. More than 500,000 copies of a glossy 20-page booklet -- called "Think Before You Agree to Drink" and costing $200,000 -- have been distributed in Brisbane in recent weeks.

The publication claims that liquid waste from morgues and hospitals, paints and solvents would be part of a "horrendous toxic cocktail" in the sewage to be recycled for drinking.

It claims that a large proportion of male fish changed sex through exposure to sewage pollutants, and that male lambs fed sewage sludge pellets behaved like females.

The booklet refers to what it describes as scientific studies that support the case against drinking recycled water.

However, four experts quoted in the publication have told The Australian that they in fact support the use of recycled sewage as drinking water.

Melbourne Water scientist John Poon is quoted as expressing concern about "longer-term health impacts from contaminants".

Mr Poon said the quote was taken from a long article, which indicated it was safe to drink recycled water. "They have misrepresented me by taking that comment totally out of context," he said.

University of Queensland biologist Peter Koopman is quoted as blaming pollutants for a 50per cent drop in male fertility rates over the past 50 years.

Professor Koopman said his comment had nothing to do with recycled water, which was not even available over those 50 years. "The implied link is nonsense," he said.

University of Wollongong engineer Long Duc Nghiem and CSIRO scientist Colin Creighton, who are also quoted in the brochure, said they were not opposed to drinking recycled water.

The publication was funded in part by John Dowson, a semi-retired land developer in the Darling Downs city of Toowoomba, where a referendum last June to introduce recycled water was defeated.

The campaign Mr Dowson funds is organised by Toowoomba councillor Snow Manners, who conceded that some experts quoted in the brochure may have been misrepresented. "They are all direct quotes but some may have been taken out of context," Mr Manners said.

"That is a reasonable thing to do. It is crucial that people realise recycled water is not a solution, no matter how desperate the water situation is."

Although Toowoomba residents voted against drinking recycled sewage by a large margin, they will be forced to do so anyway when the city is connected to the southeast Queensland water grid.

Anonymous said...

I need to give a report and my opinion is that sewage water should not be used as drinking water. Does anyone know any sites that have logical alternatives … and not sooo many words ?

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