Monday, February 26, 2007

Incidental Water Recycling at Richmond

As we have discussed previously on this blog, many communities undertake potable water reuse in an ‘unplanned’ or ‘incidental’ manner. This occurs where treated effluent from a sewage treatment plant is discharged into a waterway, which is subsequently a drinking-water source for downstream communities.

The case of the Hawkesbury-Nepean River system seems to have become a point of political disagreement in the up-coming NSW State election. So I thought it might be helpful (to all parties), to take a closer look at that particular situation. A couple of weekends ago, I placed a fresh pair of AA batteries in my ailing digital camera for a quick tour around western Sydney. This post provides a run-down of what I saw.

Click the image below for an overview of the Hawkesbury-Nepean River system.

The upper-reaches of the Nepean River extend well south of Sydney to the Southern Highlands. They include the Nepean, Avon, Cataract and Cordeaux Dams and the tributaries downstream of those dams. As the river winds north towards western Sydney, a number of sewage treatment plant (STP) discharges contribute to the overall flow, including West Camden STP.

However under current conditions, environmental flow releases from the Upper Nepean Dams (and STPs) often do not make it as far as the Wallacia Weir, which is just upstream from the Warragamba River junction. Significant wet-weather events are required in order for there to be any measurable water flow over Wallacia Weir.

For around 40 per cent of the time, the only water-flow into the river downstream of Wallacia Weir is that which is intentionally released from Warragamba Dam via the Warragamba River. The Sydney Catchment Authority is normally required to release at least 43 megalitres per day (ML/day) from Warragamba Dam to keep the Nepean flowing. However, under the current drought conditions, the interim flow release has been decreased to approximately 22 ML/day.

The first photograph below is the Nepean River perhaps 10 kilometres downstream of the Warragamba River junction. The view from ‘The Rock’ lookout near Mulgoa is spectacular and the silence is eerie. Practically all of this water has been released from Warragamba Dam and it moves very slowly along the valley floor. However, a large rain event a week earlier appears to have washed a considerable load of mud and silt from the upper river reaches. This shot is looking North East, downstream towards Penrith.

Between the junction of Warragamba River and Penrith Weir, the Nepean River receives inflow from a number of tributaries and surrounding catchment. One of the best-known views of the Nepean River is that from the Nepean Rowing Club, beside the Victoria Bridge. This photo was taken from the boat ramp behind the club and is facing back upstream towards Warragamba.

A few hundred meters downstream from the Nepean Rowing Club is Penrith Weir. The weir helps to maintain stable volume upstream. It was built in 1909 to provide Penrith with a permanent water supply. The weir forms a long pool on the upstream side of it, which extends for a distance of around 18 km and holds around 6000 ML of water. Dry weather flow releases from Warragamba Dam typically have a residence time in the weir pool of around 6 months.

Approximately 62 ML/day flows over Penrith Weir under very low flow conditions (95th percentile). Under median flow conditions (50th percentile) approximately 146 ML/day flows over Penrith Weir.

Not shown in this picture is the innovative ‘fish ladder’, which allows migratory fish to swim upstream, around the side of the weir.

Another significant source of water to the Nepean River is the Penrith Sewage Treatment Plant (STP). This plant has a dry-weather flow rate of around 22 ML/day.

Treated effluent from the Penrith STP is discharged into Boundary Creek, which is a small creak that runs along the side of the plant. As you may be able to see from the submerged reeds in the photograph below, this is a particularly fast flowing creek.

Boundary Creek flows towards the Nepean River, which it meets about 500 metres from the Penrith STP. Boundary Creek joins the Nepean about 50 metres downstream of Penrith Weir. This shot shows the creek as it is about to arrive at the river.

Here is the actual point of confluence of Boundary Creek and the Nepean River. While the volume coming from Boundary Creek is relatively constant, the relative mixing ratio is quite variable since the volume flowing over Penrith Weir is variable.

Regardless of the additional influx of water from Boundary Creek, the water depth decreases markedly downstream of Penrith Weir.

As we go further downstream, this area around Emu Plains is particularly degraded and suffers from a lack of water flow. The river reach has been significantly modified due to sand and gravel mining, producing artificial low flow velocities, which has impacted on habitat conditions. As can be seen in the photograph below, the water is highly laden with silt and numerous small islands have been formed and stabilised with trees.

This next picture is more than 10 kilometres north, taken from the end of Coolamon Road at Agnes Banks. Sadly, its quite difficult to find public access points to the river between Penrith and this point. Apart from the river banks themselves, much of the land on either side is privately owned with very few public thoroughfares. It is along this stretch of the river that another small waterway meets it from the western side. This waterway carries an additional 15 ML/day of treated sewage effluent from Winmalee STP in the lower Blue Mountains.

The river is, of course, an important source of irrigation water for many of the farms. From what I can tell, the major farming industries appear to be turf farms, citrus farms, horse studs and beef cattle studs. I couldn’t actually tell what was being irrigated in the photograph below. It appeared to be a weed farm, but was probably something more valuable.

The character of the river changes quite a bit around Yarramundi. The river narrows and the bed becomes quite pebbly. This is another major zone of the river that has been affected by in-stream gravel extraction, which occurred here between 1927 and 1989. The narrower river means that the water flows noticeably more quickly along these stretches, even during periods of relatively low flow.

The view from beneath the Yarramundi Bridge provides an instant indication of the variability of water flow along this stretch of the river.

The shot below was taken from the Yarramundi Bridge facing north. This seems to be about the point at which people stop calling it the Nepean River and start calling it the Hawkesbury River. Just around the bend to the left is the junction with the Grose River (see the next photo).

The only significant waterway to meet the river between Penrith and Richmond, which is not predominantly comprised of treated effluent is the Grose River. The Grose River is a rather underwhelming waterway, especially if it hasn’t rained in the last couple of days. In many places, the water is ankle-deep, tea-coloured and rather stagnant. A large rain event, which occurred a week prior to the below photograph deposited a large amount of silt in the lower reaches of the river. This photo is taken from Navua Reserve, a few hundred meters upstream from the Hawkesbury. In low flow conditions, the Grose River contributes around 60 ML/day.

Here we have the Richmond Bridge over the Hawkesbury River. This photo is of the southern side of the bridge looking from the western bank towards the eastern bank. It is the site of the first bridge built across the Hawkesbury. A timber bridge was built here in 1860 by the Richmond Bridge Company. The present 214 m structure was opened in 1905 and was Australia’s largest reinforced concrete bridge for over 25 years. Later widened in steel, it carried the railway extension to Kurrajong from 1926 until 1952.

It is at about this point that the river becomes tidal. In fact, when I took this photograph, the surface of the river was flowing southward (ie. back towards Penrith). I thought this was a particularly interesting observation since a number of significant sewage treatment plants (eg St Marys STP and Quakers Hill STP) discharge treated effluent into waterways that join the Hawkesbury River further downstream. In fact, the North Richmond STP discharges into the Hawkesbury little more than a kilometre downstream of the bridge. It seems inevitable that some of this water may then be pushed back to Richmond by rising tides, before subsequently being released north again by falling tides.

Roughly a kilometre upstream of the Richmond Bridge is an intake for the North Richmond Water Filtration Plant, which is owned by Sydney Water. The plant treats up to 50 ML/day by filtration through granular activated carbon and chlorine disinfection.

After treatment, the water is stored in this reservoir in preparation for reticulation. It is supplied as high-quality drinking water to 16,000 lots in the Hawkesbury region, including North Richmond, Richmond, Toorah, South Windsor, Pitt Town, Wilberforce, Kurrajong and Glossodia.

Of course, the Hawkesbury-Nepean doesn’t stop at the North Richmond Water Filtration Plant, and supplying drinking water is not its only important function. Many stretches of the river are astoundingly beautiful and, in my opinion, widely underappreciated by Sydneysiders. We have a responsibility to maintain a high water quality in the river and –very importantly- a healthy flow of water. The significant water flow is essential to keep it moving, keep it oxygenated, prevent the build-up of silt, prevent stagnation and provide an attractive habitat for native fish.

I hope you enjoyed the journey. Perhaps we’ll do the Murray River next time!

PS. I received a question from a commenter with the pseudonym ‘Interested’, who wanted to know about the ‘innovative fish ladder’, as I referred to it. Well, it looked fairly innovative to me, but a quick Google search suggests that the consensus is that it is relatively ineffectual. It is reportedly designed for trout (so that they may swim upstream). But apparently fish passage “is hindered through its design and detached aquatic vegetation and debris blocking the upstream entrance”. It certainly didn’t look blocked the day I visited, but perhaps it had recently been maintained (and of course, I couldn’t see what was below the water surface!) Here’s what it looks like:

Monday, February 19, 2007

Liverpool-Ashfield pipeline now Recycled Water pipeline

Premier Morris Iemma launched his government’s re-election campaign in Sydney yesterday. Water recycling initiatives were announced as an important component of the ALP’s strategy. Most of the initiatives -noble as they may be- were merely re-announcements of schemes previously promoted in the Government’s Metropolitan Water Plan, which was released more than a year ago.

However, the most revitalised proposal is a commitment to develop the Liverpool-to-Ashfield pipeline as a recycled water pipeline consistent with what I have previously called for on this blog. I’m hopeful that this will prove to be more than simply a re-christening, and that with careful planning it will become a highly practical piece of Sydney’s water infrastructure.

The picture below was published by The solid yellow line shows the pipeline currently under construction from Liverpool sewage treatment plant (STP) to the Ashfield sewer. The thinner orange line is the planned ‘grid link’ which is the new part of yesterday’s announcement. The dotted yellow lines are ‘potential links’, -apparently including the existing northside storage tunnel. Since the North Head STP didn’t quite fit on the map, someone seems to have made an executive decision to shift it to Mosman (who says its not a practical plan?), -or perhaps that red dot is the Taronga Zoo water recycling plant!?

I know that it would be rather naff of me to try to take any credit for Iemma’s idea, but I may just be vain enough to point out that I did energetically push the concept of facilitating recycling from the Liverpool-Ashfield pipeline a year ago, when I appeared as a witness to the NSW Parliamentary Inquiry into A Sustainable Water Supply for Sydney. While I think the opportunity is so obvious that Blind Freddy could not have missed it, the lack of enthusiasm for it (until now) has been both bewildering and frustrating. As the inquiry report stated:

4.27 Recycling treated water for agricultural purposes is considered later in this chapter. Dr Khan also notes that the infrastructure requirements of ‘large scale water reuse in Sydney’ are a key consideration of these measures [160]. Instead, Dr Khan suggests that a number of smaller treatment stations, established at intervals along the water treatment and supply route may be a more effective method of treating and supplying water for water reuse. He advised the Committee that sewage treatment plants along the Georges River, at Glenfield and at Liverpool, produce a minimum of 37 megalitres per day of secondary treated sewerage [161]. He suggests that instead of this water being reintroduced into sewers and sent to Malabar, where it is discharged into the ocean, that it could be treated to a slightly higher level and recycled:

“At the moment Sydney Water has a scheme that they are about to start implementing this year called the Southwest Sydney Sewerage Scheme and that involves building a 24-kilometre pipeline from Liverpool to Ashfield. That is going to take the sewage that is secondary treated, or greater, to Ashfield so that that will free up some of the flow in the north Georges River sub main to allow development in that area and increased capacity of that sub main. When Sydney Water talked about this they said that that pipe has the potential for maybe a sewage reuse scheme sometime in the future, or whatever, but I think that before the pipe starts being built we really need to look at who can use that sewage and we need to make sure that that pipe is planned and built with whatever requirements, in terms of pressure or flow or in terms of access to that pipe; that it is built optimally for industries between Liverpool and Ashfield to tap into it and be able to use it. Our aim should be for nothing more than a trickle of that secondary treated water to actually make it to Ashfield” [162].

4.28 Acknowledging these kinds of suggestions, Mr Nemtzow, Director General of the Department of Energy, Utilities and Sustainability told the Committee that whilst he believed that Sydney’s water management bodies were performing effectively, he also believed there was scope for improvement:

“Can we do better? Yes. Would we like to recycle it and to use the stormwater more? Yes. But for reasons we have talked about today and I know your Committee has looked at, there are limitations to that – engineering limitations, pumping water uphill, social and financial limitations. I guess I would just describe it as progress and I think it is in the right direction. I think the pace is pretty good, but there is more to go, a lot more left” [163]

[160] Submission 22, Dr Khan, p14
[161] Dr Khan, Evidence, 20 March 2006, p14
[162] Dr Khan, Evidence, 20 March 2006, p14
[163] Mr Nemtzow, Evidence, 23 March 2006, p22

According to a report in the Sunday Telegraph, the Government’s plan involves recommissioning disused natural gas pipes to help distribute the recycled water. This aspect of the plan was originally developed by Veolia Water and AGL during 2005. As the Sydney Morning Herald reported more than a year ago:

The AGL proposal involves re-using old gas mains, by lining them with plastic and, in some areas, laying new water pipes in the same trenches as new gas pipes.

Several potential customers have already been identified, including Shell, Visy Industries, Sithe Energies, Orica, Caltex and Amcor. Other customers could include golf courses, local councils and even residential customers in new housing.

All good stuff. So who’s proposal do I think is better, Debnam’s or Iemma’s?

On balance, I think they’re very similar. They both propose to use the same water from the same western Sydney treatment plants for very similar applications. Both would (of course!) press on with Sydney Water’s existing projects to further expand the dual-reticulation schemes in Rouse Hill and other new housing development areas, as well as the existing project to increase flows in the Hawkesbury-Nepean River.

Debnam has placed a higher emphasis on treatment quality in some areas so that he can “flick the switch”, as he says, to redirect some of the water to Sydney’s drinking water supplies if needed. Iemma’s emphasis is on distribution networks to deliver a lower-quality water to industry. Neither have proposed to recycle any significant volume from the three largest plants at Bondi, Malabar or North Head (however, both intend to use water from the south western plants which would otherwise end up at Malabar). Debnam has promised $25 million to “investigate further recycling initiatives” for the three large plants (which is such a miniscule and poorly defined component of his $955.7 million announcement that it barely warrants mentioning).

A greater point of difference remains on seawater desalination. Iemma is desperate to build a plant as quickly as possible, while Debnam appears to accept –at least in principle- that a dedicated approach to water recycling may be a viable current alternative for Sydney.

While engineering costs are currently experiencing a high rate of inflation, desalination technology has been significantly reducing in costs over the last few decades. This has been the result of technological improvements, as well as more players entering the market. I believe that if we can postpone the need to desalinate the ocean for as little as a decade, further technological improvements will deliver us a significantly cheaper, more energy-efficient plant, as well as much more environmentally sustainable solutions for managing the brine. A commitment to water conservation and doing more with what we have offers us our best opportunity to avoid purchasing a polluting energy-guzzler in favour of an improved later model. To achieve that, we need to take a serious look at the billion litres of water that we currently discharge into the ocean every day from North Head, Bondi and Malabar.

That’s what I reckon.

Friday, February 16, 2007

Debnam to recycle recycled water

NSW Liberal opposition leader Peter Debnam has today placed planned potable water recycling on the table for debate in Sydney. He offered an election policy involving recharging Prospect Reservoir with recycled water from treated effluent.

The choice of Prospect Reservoir seems more sensible than the alternative of Warragamba Dam, as alluded to here previously. But while he may have picked the right reservoir, Debnam seems to have picked the wrong sewage treatment plants.

Sydney Water is already making excellent progress on planning for water recycling from the inland plants such as Penrith, St Marys, Quakers Hill with the Western Sydney Recycled Water initiative. Much of the effluent from Rouse Hill is now required for the expanding dual-reticulation scheme in that area. There are still excellent and relatively simple opportunities for effluent from Liverpool, Glenfield and Fairfield to be recycled for industrial and irrigation use via the Liverpool-Ashfield pipeline.

The elephant in the room remains the three enormous ‘sewage transfer stations’ at North Head, Bondi and Malabar. This is where Mr Debnam will find well over 500 megalitres per day of available water, ripe for the picking.

Well, at least we’re having a debate about alternative water supplies for Sydney. Here’s the article from today’s Sydney Morning Herald...

Coalition water plan: treated sewage for Sydney
Anne Davies
February 16, 2007

The NSW election will officially become a war over water today when the Opposition unveils plans to divert treated effluent from inland sewage treatment plants to back up Sydney's supply in times of acute drought.

Under the Opposition's proposed $955.7 million water policy, the output from several western Sydney sewage treatment plants would be diverted to Prospect Reservoir to boost the city's water supply if dam levels fall to 20 per cent.

"If we need to boost the water supply we will use the water from the recycled sewage. It will go through two filtration plants: it will go through one and then head to Prospect to the existing water filtration plant," the Opposition Leader, Peter Debnam, told the Herald yesterday.

The scheme, which the Opposition says would cost $450 million, would add an additional 66 billion litres to Sydney water supply - about 10 per cent of the city's total supply.

When not needed, the water would be used to increase flows in the Hawkesbury/Nepean.

But Mr Debnam said it could be accessed at the "flick of a switch".

Water from the West Camden, Liverpool, Glenfield and Fairfield sewage treatment plants would be filtered through a sophisticated reverse osmosis plant. It would then be sent through a new pipeline, to be built in an old canal path either south to the river or north to Prospect, depending on the dam levels.

At times of shortage, the treated water would be shandied into fresh water at Prospect Reservoir at a ratio of about 10 per cent, Mr Debnam said. He said it would use significantly less electricity than a desalination plant.

Mr Debnam's "New Water Network" would replace the Iemma Government's planned $1.9 billion desalination plant as the immediate line of defence for the water supply, although Mr Debnam still did not rule out a desalination plant as "a last resort".

"I believe the people of NSW should be given the opportunity to have their say on how we tackle our water crisis, before the election. They should be given a clear choice and we will give it to them."

Mr Debnam said he had complete confidence in the technology, which he said could deliver safe drinking water.

"I don't have a problem with it. We are saying let's have a debate. They are trying to deflect attention that they haven't done the work on recycling. This technology has been available for a decade."

He said a Coalition government would establish a Water Excellence Panel and appoint an independent water commissioner.

A second part of Mr Debnam's new water network is a $470 million scheme to link inland treatment plants in north western Sydney to deliver an additional 20 billion litres of water as environmental flows into the Hawkesbury.

But last night there were doubts about whether the Opposition was double counting water that is already being recycled. The water from the Liverpool treatment plant is due to be piped to Ashfield for industrial uses. Some is also allocated for its industrial recycling initiative at Camellia.

The output from the Penrith, Rouse Hill, St Marys and Quakers Hill plants is already being used for recycling under the Government's western Sydney recycling initiative. But the Opposition says there is a further 20 billion litres that is not being recycled.

The Opposition will also spend $25 million on investigating further recycling initiatives for ocean outfalls.

The Minister for Water Utilities, David Campbell, said last night the Government's insurance policy was desalination. "We will build the 125 megalitre plant, and if dam levels dropped further, we would be able to upscale the plant quickly to 500 megalitres per day - which is about one-third of Sydney's daily water needs."

Here's the front page of today's Daily Telegraph... Just like Warnie a couple of weeks back, Brett Lee doesn't look happy with the news. What is it with these cricketers?

Sunday, February 11, 2007

Iemmanomics of IPR 'vs' Desal for Sydney

Let’s talk about money for a bit. Let’s put on a purely economic rationalist hat (or perhaps suit and tie) and think solely about cold hard cash for a few minutes.

If I had a dollar for every time I’ve been told on this blog that ‘money doesn’t matter’, -well I might be able to afford a two litre bottle of Evian mountain spring water by now. However, the uncomfortable fact is that money does matter. Money that we spend to produce and deliver drinking water where we could have produced and delivered the same volume and quality at lower cost by other means, is money that is not available for other things (think schools and hospitals). The economists amongst us (G’day Snow) call it ‘opportunity cost’ and the social implications are worth considering carefully.

So putting aside factors such as environmental impacts of desalination brine, it behoves us to ask “which costs more, -desal or recycling?”. As I will try to explain, the answer is frustratingly complex, highly scheme-specific, city specific and depends on who’s doing the sums! However, I expect that taking a closer look at the question might help us to identify some of the snags along the way.

A story in the Daily Telegraph this week reported that “NSW Premier Morris Iemma says adding treated sewage to Sydney's drinking water supply would cost at least twice as much as his planned $1.9 billion desalination plant.” Iemma apparently stated that adding “treated sewage” to Sydney’s drinking water supplies would come at a capital cost of $4 billion to $5 billion (what's an extra billion between friends?).

Even our friends at 4350 Water suggested that Iemma might perhaps be out on a bit of a limb here. Indeed, Sydney Water published a cost-comparison just under a year ago (March 2006). This comparison estimated overall capital costs for a 500 megalitre-per-day desalination scheme at $2.5 billion and a 500 ML/day indirect potable recycling (IPR) scheme at $3.8 billion.

Iemma’s desalination discount (from $2.5 billion to $1.9 billion) is possibly explained by the fact that the scheme will now initially be built with a capacity of only 125 ML/day (expandable to 500 ML/day at a later date). How IPR went from $3.8 billion to $4-5 billion has not been explained, but presumably accounts for the massive rate of inflation currently applied to major engineering projects.

We have previously discussed why reverse osmosis treatment of seawater is always going to be more energy-intensive, and thus more expensive, than reverse osmosis treatment of municipal sewage effluent. I think that point is inarguable in the absence of some significant technological advances. However, reverse-osmosis treatment alone constitutes neither a seawater desalination scheme nor an IPR scheme, -both have many other components and are much more complex than just a shed full of membranes.

A 500 ML/day IPR scheme would indeed be a relatively expensive development in Sydney. The greatest difficulty lies with the fact that our major sewage treatment plants are at sea-level on the coastline (North Head, Bondi and Malabar), while our drinking-water reservoirs are inland and elevated. The concept of IPR requires some form of environmental detention, usually in a river, reservoir or aquifer. To transport water from the treatment plants to a drinking-water reservoir in Sydney would require pumping large volumes westwards to higher altitudes.

A second complication is that the term ‘treatment plant’ is somewhat of a misnomer for the plants at North Head, Bondi and Malabar. I think ‘sewage transfer station’ would be a more appropriate term since their function is primarily to transfer water from the sewage system to the ocean. The only treatment that takes place is rapid ‘primary treatment’. This involves collecting a few of the heavier solids by scraping them off the bottom of a tank that the water flows through on its way to the ocean outfall. Most cities would calculate the cost of a water recycling scheme starting with the assumption that the available sewage effluent would be at least secondary-treated. However the cost of treating the water from these three Sydney plants for recycling needs to factor-in the additional cost of preparing the water by secondary sewage treatment.

Sydney Water’s comparative cost analysis suggested that the overall capital costs of building a 500 ML/day seawater desalination scheme or an IPR scheme of the same size were differentiated predominantly by costs associated with transporting and connecting the water to the potable supply system. This assumed that desalinated seawater could be transferred from Kurnell to Waterloo (practically on the coast), while recycled water would need to be transferred from Malabar all the way up to Nattai (in the lower Blue Mountains, elevation 160 m) above Warragamba Dam. It seems obvious to me that Prospect Reservoir would be a closer, lower altitude and more practical location to transport the water to and I have no idea why this was not considered.

In Sydney Water’s analysis, the infrastructure costs for water treatment were also estimated to be slightly higher for IPR than for desalination. This arises largely because of the need to build a secondary sewage treatment plant (on prime real estate) at Malabar.

Furthermore, Sydney Water’s costings include the assumed need to pump water from both Bondi and North Head, all the way across the Sydney coastline to Malabar for treatment. The reason why this would be required (to produce 500 ML/day) is not clear since Malabar produces a dry weather flow of 456 ML/day and Bondi 130 ML/day. So assuming 80 % efficiency and a bit of wet weather, water from across the harbour at North Head should not be required.

Even once the plants are constructed, Sydney Water’s calculations assume a slightly higher annual operating cost for the IPR scheme ($175 million/year) compared to seawater desalination ($165 million/year). However, again these costs for IPR arise largely from the cost of secondary sewage treatment (which any other developed city would take for granted) and pumping water all the way to up to Nattai, above Warragamba Dam.

The Sydney Water cost comparison does not canvas alternative IPR options or variations. However, it does include the following paragraph towards the end:

“Finally, it is noted that the costs of desalination and IPR at a scale of 100ML/day are likely to be far more comparable. This is because at this scale there would be two sources of cost savings for an IPR project. First, at this smaller scale wastewater for an IPR project could be sourced from treatment plants in Western Sydney. These treatment plants produce a higher quality wastewater that would require less treatment for IPR. Second, due to the shorter distance from Western Sydney to the Warragamba Dam, the transfer cost would be lower than they would be for the 500 ML/day coastal plant”.

Sydney Water’s cost estimations have been revisited by the private company, Services Sydney. Even including the cost of secondary sewage treatment and pumping to Warragamba Dam, Services Sydney calculated reduced capital and annual operating costs for an IPR scheme compared to Sydney Water. While the IPR capital costs still exceeded the desal capital costs, annual operating costs were lower for IPR. So, by considering capital and operating costs over a 50 year period (with a 4% depreciation rate), Services Sydney came up with an IPR cost close to $6.1 billion and a desalination cost of $7.4 billion.

Certainly, the fact that Services Sydney have a clearly stated financial interest in water recycling should not be overlooked. However, I think this demonstrates that the figures ultimately calculated depend largely on who’s doing the sums. They also depend significantly on the assumptions made, as well as specific characteristics of the scheme and city being considered.

What figure does your calculator give?

Thursday, February 08, 2007

Fish Beware

The Honourable members met for question time in the Queensland State Parliament yesterday. If you appreciate -as I do- good theatre, then the script from the Hansard record is worth a read.

I don’t think this requires any further commentary from me. So grab yourself a king-size tub of popcorn, put your feet up on the seat in front, and enjoy…

Purified Recycled Water

Mr LEE: My question is to the Premier. Could the Premier inform the House about the former leader of the National Party’s attempts to undermine the future of Queensland’s food producers as part of a scare campaign against purified recycled water?

Mr BEATTIE: The answer is yes. I was not surprised but I guess disappointed that the former leader of the opposition was out scaremongering about recycled water—scaremongering is what he did. He raised issues about food. Let us talk to the experts; let us not talk to those people who have trouble accessing and understanding the Net.

An opposition member interjected.

Mr BEATTIE: Please, for once, just don’t be rude. Mark Panitz from the peak horticultural group Growcom—those opposite know Growcom—has dismissed the argument and says that the claims are not helpful. He states— Food safety systems are in place so that we can guarantee our consumers and buyers, wherever they are around the world, that our product is really pure and very safe. What do the farmers say? The farmers agree with us; that is the first thing. The second thing is that the former leader of the opposition—

Opposition members interjected.

Mr BEATTIE: They are being rude again. Can those opposite actually ever not be rude? Is there anyone decent with any manners over there at all?

Mr SPEAKER: Order! The Premier is on his feet.

Mr BEATTIE: Let me come to the second point. The former leader of the opposition then went on and said that he had got on the Net and checked out Thames Water. He says that they basically do not have recycled water. I do not know where he checked that out but the fact is that they do. The former leader of the opposition, who wants to be a recycled leader, says that he got on the Net and checked it out. What is the story? Here is a report from Thames Water, which states—
The river Thames is used as a disposal route for effluent from 350 waste water treatment plants including some of the largest in Europe. Indirect re-use of treated effluent further downstream contributes about—

Mr Springborg interjected.

Mr BEATTIE: You don’t need to be rude either.

Mr STEVENS: I rise to a point of order. The Premier is misleading the House. I have checked this matter out—

Mr SPEAKER: Take your seat. There is no point of order.

Mr BEATTIE: Just as well that we do not have an IQ test. What those opposite do not want is the truth because what it says is this—

Opposition members interjected.

Mr SPEAKER: I indicate that the Premier has time to answer this question and I would like to hear him answer it for you.

Mr BEATTIE: Those opposite want to turn this place into a circus. Let me be frank about something—

Mr Seeney: Yeah, we’ve already got a clown.

Mr BEATTIE: We know where you fit into the circus. The former leader of the opposition has raised a serious issue about recycled water in London. I am trying to explain exactly what the government’s position is—

Mr Hobbs: Not true. Tell the truth about it. Tell the truth.

Mr SPRINGBORG: I rise to a point of order. We had a briefing from the Water Commission’s expert panel professor yesterday, Mr Greenfield, who said that they do not recycle one zack of their own water back into their own supply, not one zack.

Mr SPEAKER: Member for Southern Downs, if you continue to wilfully disregard my authority as Speaker you will be outside. I ask all members to respect and not disregard my authority as Speaker of this House. I will say to all of you, whichever side it is, if you continue to do it you will be outside in a hurry.

Extension of Time

Hon. RE SCHWARTEN (Rockhampton—ALP) (Leader of the House) (10.49 am): I move—
That the Premier be further heard.

Mr SPEAKER: It has been moved that the Premier be further heard.
Leave granted.


Mr BEATTIE: I make this point: it is very sad that on an issue of recycled water we cannot have a position where you can come in here and put your case and I can put my response. If you want to wreck this parliament, which is what you are doing—

Mr Springborg: Just give us a chance.

Mr BEATTIE: If the opposition parties want to wreck this parliament, you will destroy its credibility in the eyes of the community. It is about time you actually started to behave appropriately.

Mr SPRINGBORG: Mr Speaker, I rise on a point of order. The Premier is deliberately distorting the privileges of this place. He knows we do not have the same opportunity that he does.

Mr SPEAKER: There is no point of order. The member for Southern Downs will take his seat.

Mr BEATTIE: There is a 5.30 pm debate. You could have moved this as a motion for tonight. If you were still the Leader of the Opposition, you could have put this on tonight or you could have spoken to your successor.

Ms Bligh: He spoke yesterday in the Address-in-Reply!

Mr BEATTIE: Not only that, you spoke in the address-in-reply debate yesterday. You were in the parliament yesterday. I am simply trying to clarify the record so that your scaremongering goes nowhere, but you want to wreck the parliament. There used to be a time when the National and Liberal parties actually stood for the institution of parliament. People like Sir James Killen actually stood for something. All you do is stand for wrecking.

Honourable members interjected.

Mr SEENEY: I have a point of order, Mr Speaker.

Mr BEATTIE: Here it is again, Mr Speaker.

Mr Lucas interjected.

Mr SPEAKER: I would ask the Minister for Transport and Main Roads to desist. Is this a point of order?

Mr SEENEY: Absolutely.

Mr SPEAKER: I call the Leader of the Opposition.

Mr SEENEY: I think the Premier should look up the dictionary and find out what ‘plagiarism’ means. He is copying my speech from yesterday.

Mr SPEAKER: Can I say—

Mr SEENEY: I find his assertions—
Procedure—Speaker’s Ruling—Withdrawal of Disorderly Member

Mr SPEAKER: Order! Sit down, please. I say to the Leader of the Opposition that I have already warned you. Under the provisions of standing order 253, having previously been warned, I now ask the member for Callide to withdraw from the chamber.

Mr LINGARD: On a point of order—

Mr SPEAKER: Excuse me! I am on my feet. I asked the member for Callide to withdraw from the chamber under the provisions of standing order 253.

Mr Seeney: Mr Speaker, with the greatest of respect—

Mr SPEAKER: I am on my feet and you will sit down. The wilful disregard for my authority as chair is about to finish. I have asked you to remove yourself from the chamber. If you do not remove yourself from the chamber, you will find yourself under standing order 254.
Whereupon the honourable member for Callide withdrew from the chamber.

Mr LINGARD: Mr Speaker, on a point of order: I remind you that on the first occasion you warned the member for Callide for interjecting. The second time you warned him for taking a point of order. That is completely wrong. You might warn him twice for interjecting—

Mr SPEAKER: There is no point of order.

Mr LINGARD:—but the first time was for interjecting and the second time was for a point of order.

Mr SPEAKER: There is no point of order. Take your seat, please.

Mr BEATTIE: Mr Speaker, all I have tried to do this morning is explain what happens in London.

Mr Hobbs: Tell the truth!

Mr BEATTIE: Hang on. Wait a minute. I have the right to put a point of view and you have the right to disagree, but surely you should not wreck this place—

Mr LINGARD: On a point of order, Mr Speaker, when are you going to make the Premier speak to you directly rather than address all of us as ‘you’, ‘you’, ‘you’?

Mr BEATTIE: Mr Speaker, I always speak through you and, if I have not, I offer my apologies to the chair.

Mr SPEAKER: I ask the Premier to ensure he constantly talks through the chair.

Mr BEATTIE: I will. Mr Speaker, let me try to explain what happens in London without the
scaremongering we have been having. Let me come—
Opposition members interjected.

Mr SPEAKER: Order! We are continuing to have these constant interjections in the House. You are all parliamentarians from different parties, and I am asking for order. I do not want to go down the same track that I have with one member this morning, but if you continue to absolutely disrupt the business of this House that is what will happen. It is my absolute last resort. I have actually given a ruling today in that regard before. I call the Premier.

Mr BEATTIE: As I was saying, the Thames water report states that the River Thames is used as a disposable route for effluent from 350 waste water treatment plants, including some of the—

Opposition member interjected.

Mr SPEAKER: I think you should just keep going, Premier. I will warn the person who is interjecting. I do not know who it is at the moment.

Mr BEATTIE: That includes some of the largest in Europe. This is the important point: indirect reuse of treated effluent further downstream contributes about 12 per cent of the available resources for public water supply in an average year. This is what it does to London water. In other words, if you are in London and you are drinking water, in an average year you will drink 12 per cent. That is what happens in London. It goes into the river and it flows down the river and then different places extract the water and you drink it. That is how it works. However, in parts of the lower basin, that figure can rise to nearly 70 per cent during a dry summer. That is what happens in London. What we will be doing here is better than that because our reverse osmosis process will make it cleaner. It will make it better than that. When I ask, ‘Have you been to London and drunk the water?’ the answer is that, yes, you then you have drunk recycled water. If you go to Singapore, you will find that ours will be treated better than that in London. If you go to Washington, Berlin or the Orange County, you will find that ours will be treated better than their water. I just say to the former Leader of the Opposition that it is about time you told the truth about this. The reality is very clear. That is what the report says; it is black and white. As for the reverse osmosis process that will operate under our system, what happens in Singapore—and forget about London, because Singapore and our water will be better—

Mr Springborg: One per cent.

Mr BEATTIE: The former Leader of the Opposition says one per cent. Do members know what he is talking about? He is talking about what happens in Singapore, which is about to be increased, by the way.

Mr Springborg: To 2½.

Mr BEATTIE: Yes, that is right, to 2½ per cent, and thank you for making the point. The reality is this: where there is a reverse osmosis process and the water is treated, it does not matter whether it is one per cent, two per cent, three per cent or four per cent; it does not matter whether it is 95 per cent. If one per cent is good, it is all good. That is the point about reverse osmosis. The member’s point about one per cent does not matter. The member’s point about 2½ per cent does not matter. At the end of it all, you can say what you like about this because it is a democracy. But the truth is, Mr Speaker—and I want to be clear about this—people around the world drink it. Our water quality will be better than London’s. The only relevant point out of what was said by the former Leader of the Opposition—who wants to be a recycled Leader of the Opposition by the way he is going—is that in fact what happens in London will not be as good as what will happen here. Our water will be cleaner. I just say to Mr Springborg, the member for Southern Downs, and to all the other members who want to disrupt this: at the end of this, this is in the state’s interests. The water is safe, it is good quality and it will be better than what you are drinking now.

Mr DICKSON: On a point of order, Mr Speaker: the Premier is telling this parliament he is misleading parliament saying it is 100 per cent safe.

Mr SPEAKER: There is no point of order. Can I just remind some of the new members from both sides who are here that a point of order does not allow you to debate the issue. It is open for debate if a motion is before the parliament. You are trying to debate the issue. There is no point of order. I call the Premier.

Mr BEATTIE: The final point I want to make is this.
Opposition members interjected.

Mr McARDLE: On a point of order, Mr Speaker—

Mr SPEAKER: Come on! Let’s just get on with the business.

Mr BEATTIE: I have two final points. If the opposition had not been disruptive, this would have been finished a long time ago. This is your question time. You are wrecking it. If you had let me finish, this would have been done. I just say two things in conclusion. Fish need not worry because their sex will not be changed by recycled water. I want to make that really clear. We do not need to put up a label saying, ‘Beware fish. Your gender will be changed.’ I want the former Leader of the Opposition to know that. We do not have to put up signs saying ‘Fish beware’, because their gender will not change. As for the new member representing the Sunshine Coast, your nonsense about AIDS and all the other things is irrelevant; it is just rubbish. Do not go out and scaremonger. It is not in the state’s interests.

Western Corridor Recycled Water Project

Mrs MILLER: My question is to the Deputy Premier, Treasurer and Minister for Infrastructure. I ask: can the minister update the House on progress with the western corridor recycled water project?

Ms BLIGH: I thank the honourable member for Bundamba for her interest in this issue generally and her interest specifically in the considerable amount of work that is now occurring in her electorate to make this pipeline a reality. The western corridor recycling pipeline project takes bulk water recycled from Luggage Point on Brisbane’s east to Caboonbah in the north-west. It involves the construction of three advanced water treatment plants—one at Bundamba, one at Luggage Point and one at Gibson Island. These will be state-of-the-art, world-class facilities in terms of the technology that they will be using. The overall length of the pipes is approximately 200 kilometres with a combined capacity to supply the water savings target of some 210 megalitres a day. Completion for the overall project remains on target for December 2008. This is a huge project. Just to give members a sense of the size of the effort, today there are 809 people employed on this pipeline project alone. By July that will peak at 2,650 workers on the project. There will be more than 1,000 workers in the electorate of the member who asked the question—at Bundamba alone—by July this year. The project reports that targets for recruitment are being met despite what everybody knows is a very tight labour market. We are well on track to making recycled water for industry, for drinking purposes and hopefully for agriculture as soon as possible. It is clear from the debate in the public arena and the debate here this morning that the success of this project is not going to be assisted by any intelligent contribution from those on the other side. I want to take the opportunity this morning to thank the member for Moggill for the leadership that he has shown on this issue. I know only too well that this is a tough issue on which the community has very mixed views and it requires a bit of backbone to stand up and talk about how necessary it is. That is what the member for Moggill has done. I know there has been a lot of criticism of his leadership from time to time. However, we have seen him stand up from day one and provide support and some real comfort from a scientific point of view to the community. That, however, does not represent the one team, one plan, one destiny approach that we have heard so much about. Honourable members have seen here this morning the member for Southern Downs—and they will have heard him yesterday— running around scaremongering. I am very sorry that the member for Moggill does not seem to be able to control his own backbench with the member for Kawana also jumping on the bandwagon. I do think it is important that people understand that there will be scaremongering on this. I draw to the attention of honourable members this document that says, ‘Think before you agree to drink’. This is the document that has been prepared by Councillor ‘Snow’ Manners from Toowoomba. I understand that he is hoping to distribute it across south-east Queensland. This is the document on which the member for Southern Downs presumably bases his wild claims about the sex changes of fish and further claims about endocrine disruption compounds. It is probably the most intellectually dishonest document I have seen.

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.


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!