Desalination. Part 2.

12 years ago I posted my thoughts on the building of Sydney's Desalination Plant in Kurnell. A few days ago, the NSW Government announced plans to double the size of the output. A doubling of its size was actually planned for when it was designed, so the cost will not be as great.

As a result, the expanded Kurnell Desalination Plant will be able to supply 30% of Sydney's water needs.

Desalination plants are all over Australia. Apart from Sydney, there are plants in Melbourne (33% of supply), SE Queensland (27%), Adelaide (50%) and two in Perth (37%).

But according to the Australian Bureau of Statistics, water consumption by households represents only 12% of water consumption (1,909,075 Megalitres out of a total of 16,558,203 Megalitres in 2016-17). Agriculture represents over 60% of consumption (10,305,491 Megalitres in 2016-17). The rest is used by mining and industry.

In my original article, I pondered the potential of switching over to desalinated water for all of Australia's needs, including agriculture. In the years since, I have learned that the total cost of such a venture would be very, very high. And yet in the face of Australia's worst drought on record and massive bushfires, the cost of not acting may be even higher.

Australia's agricultural heartland is located along the Murray / Darling / Murrumbidgee river areas. These rivers have provided irrigation water for over a century to farmers. Yet it appears as though these rivers will no longer be able to supply the water necessary - even the Murrumbidgee and its reliance upon the water diverted by the Snowy Mountains Scheme is finding it difficult.

The best desalination solution would involve a series of very large desalination plants built on the coast and close to the river systems. These areas would be the mouth of the Murray in South Australia and also the coastal areas of SE Queensland.

As with Kurnell and other Australian plants, these new plants will be built along with renewable energy plants to power them. Solar and Wind farms can be built in appropriate areas and connected to the grid.

Snaking up from these huge desalination plants would be clean piped water, following the river systems through the current agricultural areas. These pipes would snake up the Murray from the Murray mouth, and along the Murray in Western NSW and the Murrumbidgee in the South of NSW. From SE Queensland, the pipes would be built along to the Southern Downs, where it would snake down various tributaries of the Darling such as the Barwon, and would connect up to the pipes from Murray mouth, creating a huge water grid accessible by farmers in SE and SW Queensland, Northern, Western, Southern and South Western NSW, Northern and Western Victoria, and Eastern South Australia.

With a 100% guarantee of water, farmers and farming communities would be assured of their future, along with an assurance of food production in a future where global warming will cause substantial drought all over the world. The presence of water will also allow for the growth of secondary industries and the growth of rural towns. It may be that people will flock to these areas for work, especially if world food prices grow.

Of course there will need to be common sense practices to accompany this. Irrigation water will be delivered through pipes rather than canals - the less evaporation the better. Steps must be taken to ensure that land degradation from salinity and inappropriate crops is minimised. It is also possible that farms in these areas would be covered to reduce transpiration from the crops and minimise insecticide usage.

One concern would be the output of brine from the desalination process. This is something that people have questioned for a while since large scale desalination plants first became operational. Would the brine create a high-salt, low oxygen dead zone around the outfall pipes, killing sealife?

What needs to be kept in mind here are two things. The first is the proportion of water used compared to the amount of water in the world's oceans. The second is the Water Cycle.

The amount of water in the sea is staggering. Compare the amount of water in the world's oceans to the amount of water humans need to survive and the result is, very, very, very large. If humans desalinated all their water needs, the impact it would have on the world's oceans is minimal. The outlet pipes of desalination plants do not release enough brine to poison the ocean - the brine mixes in with normal seawater and moves via currents and wind. The only concern would be if water from an enclosed salty body of water is desalinated - these would include the Dead Sea, the Aral Sea and the Caspian Sea.

The water cycle is also important here. Water, when used, doesn't disappear. Consuming water doesn't destroy it, it just changes form. The water we drink for our bodies to live is matched by the amount of water our bodies produce - sweating, urination, defecation and evaporated water from breathing. In the same way, water used in agriculture is exchanged - transpiration from plants and an increase in groundwater will occur from irrigation. In all these cases, the water we consume eventually makes its way back into the atmosphere and into the ocean.

The cost of creating a network of desalinated agriculture of the sort I have described above will be huge. The cost of building Kurnell was $1.8 Billion. The cost of building my proposal is likely to be over $1 Trillion. But over a build period of, say, 20-30 years, the costs will be manageable and affordable when compared the Australia's annual GDP (which is around $1.4 Trillion today).

In my 2008 article I mentioned the following:

"While spending 5-6 months in drought-stricken country NSW in 2006, I asked a number of farmers about water supply. "Would you", I asked, "be prepared to pay premium prices for water if its supply can be 100% guaranteed?" They all said yes."

I still believe that this is the case today.

Effects of the Kurnell Desalination Plant

Sydney's Kurnell Desalination Plant began operating during the first week of February 2010. At full capacity it produces some 250 megalitres a day of potable water. As I flew from Sydney to Launceston yesterday, I managed to glimpse it through the window as we flew over Kurnell.

It has not been a great time for proponents of desalination plants, at least in Australia. Popular opposition to the plants focuses upon the greenhouse gases produced by the increased energy needed to operate the plant (a problem offset by the co-construction of a wind farm that produces more kW-h over a 12 month period than is consumed by the desalination plant), the added cost it places upon tap water (which is only a problem when water supplies are not low) and the pollution caused by pumping brine back into the sea (a process which causes increased salinity in the affected area but is also a natural part of the water cycle).

Another problem is that the plant has begun operating during a severe La-Nina event which is known to cause high rainfall levels in Australia. The plant was conceived and built during an El-Nino period when Australia was suffering prolonged drought and low rainfall.

Over the past year I have been collating data from the Sydney Catchment Authority which runs a weekly data series on Sydney water storage and supply - specifically the amount of water gained and pumped by Sydney's network of dams. When compared to the previous six years (2004-2009), 2010 stands out as the year the least amount of water was delivered from dams - a direct result of the increased supply of the Kurnell Desalination Plant.

According to the Data I have collated, the average amount of water delivered from the first week of February to the second last week of December is 466,438.91 megalitres. In 2010, the water delivered in this period was 387,674.83 megalitres, which means that the Desalination plant prevented up to 78,764.08 megalitres from being pumped from Sydney's dams.

At the time that this article was published, Sydney Dam levels have risen to 1,863,500 megalitres, mainly as a result of increased rainfall. This represents 72.2% of capacity, the highest since 2002. If we do the math, we prove that, since 78,764.08 megalitres was saved due to the desalination plant, then we can expect the current dam levels to be 3.1% less than what they currently are - 69.1% - if the desalination plant was not operating.

Moreover, simply by crunching the numbers already shown above, we can see that the desalination plant produces around 17% of Sydney's water - at least if we compare 2010's results with the averages of 2004-2009.

The Kurnell plant was built with the understanding that it would be "mothballed" during periods of high dam capacity. It was also decided that the plant would run continuously for two years to iron out any problems before any "mothballing" would occur, so the chances are that the plant will continue to operate throughout 2011 no matter how full the dams get.

The Kurnell plant has been designed to allow for a doubling of capacity if needed - land has been set aside at the site for more buildings and the piping to and from the plant has been designed to allow for a doubling of capacity. If rainfall levels in Australia and Sydney continue to decline (despite the recent wet weather) then increasing the capacity of the plant will be a cost effective solution to any declining dam levels.

Since it would be more efficient to operate the plant for long periods and mothball it for long periods (as opposed to short periods for both), I would suggest some sort of "trigger" mechanism to be put into place:

* 75% Capacity: The plant will be shut down and mothballed once stored water supplies reach 75% capacity.
* 50% Capacity: The plant will begin operating once stored water supplies dip below 50% capacity.
* 25% Capacity: The plant will be doubled in size once stored water supplies dip below 25% capacity, or else another desalination plant built if this has already happened. (This assumes that the plant has been operating continuously since supplies dropped below 50%)

I support Desalinisation plants

But only if they're built right.

Desal plants have been used for many years to turn seawater or brackish water into fresh water. Unfortunately, Nimbys pretending to be Greenies tend to complain too much when these sorts of things get built - at least here in Australia. Desal plants are slated to be built in Sydney, Melbourne and somewhere in South Australia as a result of the long drought we have been experiencing.

Here are my reasons for supporting Desal plants:

• They provide perfectly drinkable water.


• The technology is proven (and it is also improving).
  


• It can "drought proof" both city and country areas.

Here are some common complaints, followed by my reply.

Desal plants use lots of electricity, which means they are bad for the environment.

Yes it is true that they use lots of electricity, but it is only bad for the environment if the electricity is produced by fossil fuels like coal or gas. If the electricity grid is switched over to "Green" power like wind or solar, then Desal plants won't be bad for the environment. It is not the consumption of power that is the issue, but where the power is sourced from.

Desal plants produce a brine slurry that will pollute the sea nearby.

The production of a brine slurry - essentially thickened seawater - is a byproduct of the desalinisation process. When the water is removed from salt water, obviously what is left behind is salt. If this slurry were simply dumped back into the sea in one spot it would have negative environmental effects on coastal areas nearby. If the slurry were pumped further out and dispersed somewhat (or even diluted with seawater before it returns to the sea) then the effects would be minimal. The reason for this is that the sun evaporates plenty of water from the sea every day, leaving salt behind. Adding salt to salt water would be like adding slightly more Nitrogen to the atmosphere (but only if it is dispersed - too much in one spot is a no no I believe).

Alternatively, the slurry could be dried out and the salt turned into table salt. Salt is a product that is purchased and sold in the marketplace, which means that it is not really a waste product at all (Australia is a salt exporter). Salt can even be used to augment cement (see here and here). Moreover, sea salt is sodium chloride, and chlorine can be extracted from the slurry - a chemical that has many industrial uses.

We should recycle used water from our sewerage system instead.

There's a guy from my church who is involved in the design of alternative energy systems, and he talks about this as "the yuck factor" - people don't really want to drink their own waste water. This, however, can be overcome through public education. Moreover, there are places around the world which recycle their waste water effectively and the population are fine about it.

In order to remove the nasty bacteria, chemicals and particulates from the waste water, an industrial process needs to take place which achieves this. It would involve either boiling the waste water at a low air pressure, or some form of membrane process involving reverse osmosis. What sort of "thing" could achieve such an industrial process? Why a desal plant of course! It doesn't have to use seawater all the time. Waste water could easily be diverted to a desal plant and converted into drinkable water.

Desal plants are only good for people on the coast who get good rainfall already. It would be too expensive to pump water inland to be used for irrigation.

Such a process - whereby desal plants pump irrigation quality water to inland parts of Australia where they are used for irrigation - is very expensive, but not prohibitively.

While spending 5-6 months in drought-stricken country NSW in 2006, I asked a number of farmers about water supply. "Would you", I asked, "be prepared to pay premium prices for water if its supply can be 100% guaranteed?" They all said yes.

Building thousands of kilometres of pipelines around inland Australia (mainly in NSW, Victoria and South Australia) to create a "water grid" that can guarantee water supply for farmers is an expensive proposition. Yet I would think that the price that farmers and towns are willing to pay for the water would make up for it, so long as their costs are less than the gains they would make by having a guaranteed crop, year after year. Moreover, if the cost of water is quite expensive, then steps would be taken by farmers to minimise its usage and to maximise crop production. It would also encourage crops that need less water (like wheat) over crops that need lots of water (like rice).

If I were president

Slashdot is running a comments thread, asking contributors what they would do if they were president. It's a common thing for people to do. In fact, author Tom Clancey indulged in this idea when he wrote Executive Orders (I was half-way through the book when I suddenly realised that Clancy was being Jack Ryan and was essentially promulgating his political philosophy through that character).

So, anyway, this is what I would do:

1. Get the secret service to cover up the fact that I am not American.

2. Announce that all troops will leave Iraq within 3 months.

3. Convince the UN to send peacekeeping forces to Iraq.

4. Raise taxes on higher income earners in order to run a fiscal surplus and pay back government debt.

5. Introduce universal health care (and raise taxes to pay for it).

6. Convince the Federal Reserve Bank to have a strict inflation targeting guideline. Obviously I would want zero inflation but, realistically, I would argue that the Fed should aim to keep inflation below 2% continually.

7. Get the Air Force to meet with the Navy Air Wing and the Marine Air Wing and state that they have to use the same planes.

8. Ban the sale of new gasoline-powered automobiles by 2016. This will give the auto industry 8 years to develop and sell zero-emission cars.

9. Ban the operation of all power stations that directly emit CO2 by 2020. This will give the power industry 12 years to set up enough solar and wind generators to replace them.

10. Ban oil, coal and gas production by 2020.

11. Close Guantanamo Bay and give it back to Cuba.

12. Pay all women aged between 18 and 40 $3000 per year to have a reversible Tubal ligation if they want to. This will prevent many women from conceiving and will lower abortion rates drastically. If the woman wants to have children, she can have the process reversed.

13. Give Puerto Rico the choice of either becoming a state of America or becoming a sovereign nation - which is better than what the current situation is.

14. Get all government departments to use Linux and other open-source software rather than proprietary software.

15. Create a "Department of Information" which would then employ thousands of writers full time to work on Wikipedia.

16. Provide the Wikimedia foundation with enough money to keep it running for 50 years.

17. Remove all farm subsidies and tell the farmers that the government isn't going to pay them to grow crops anymore. They will have the freedom to grow whatever they want.

18. Create a national water grid to drought-proof the nation. This would involve the creation of desal plants on the coast pumping irrigation-quality water inland. A market for this water would also be created, ensuring that water is both available and priced accordingly.

19. Allow prescription Heroin and Cocaine for addicts.

20. Pay $1 Billion each to the members of Ride for them to reform.

Irrigators running out of water

From the department of water-water-everywhere-so- let's-all-have-a-drink:

The New South Wales Government says irrigators in the Murray-Darling Basin only have enough water to last them about another six weeks.

The state Water Minister, Phil Koperberg, is visiting the region today to discuss the options available to irrigators.

Mr Koperberg says the price of water in the area is now up to 10 times higher than it was this time last year.

"This is one of the manifestations of the way in which water is traded these days," he said.

"As a consequence, because of the dire shortage, it's once again a case of supply and demand.

"The water price is exceedingly high this morning."

He says irrigators' livelihoods are "rapidly disappearing".

"So once again, for the fourth time, I'm heading down there today because I want to hear from the irrigators themselves to see what their views are to see what they believe governments might avail themselves of to assist," he said.

"It's a question of just working through this crisis at the moment."

The good news at this present moment in time is that the La Nina indicators are very good, which means that there is a chance that the drought will break soon with above-average rainfall. The bad news is that, generally speaking, this is the "dry season" for south-eastern Australia.

I still think there is merit in building a desal plant, preferably near Adelaide, which would pump irrigation-quality water inland to be used in dry area farming (wheat). The cost of building the plant and pumping the water would be charged to the farmers, who would then factor in the price of the water into their grain costs. Having spoken to some farmers in Griffith last year, I can confidently say that farmers would be happy to pay such a cost for water if they can be guaranteed supply and a regular crop.

Moreover, the Desal plant could be powered by wind and/or solar and the farmers would be forced to use water-saving irrigation techniques to prevent salinity problems. Some of the water could also be used to create forests in the desert to help mitigate global warming.

Wheat prices rise to US$9 per bushel

From the department of a- quart- of- wheat- for- a- denarius- and- three- quarts- of- barley- for- a- denarius- and- do- not- harm- the- oil- and- wine:

Sept. 12 (Bloomberg) -- Wheat prices surpassed $9 a bushel for the first time as a drought in Australia cut production, pushing global stockpiles toward a 26-year low.

Australia's wheat crop may be forecast at 18 million metric tons from a previous prediction of 23 million tons in a U.S. report today. In Canada, the world's second-largest wheat exporter, reserves of the grain plunged 29 percent at the end of July from a year earlier, Statistics Canada said yesterday.

Rising prices of food, from wheat to milk and pork, are stoking inflation at a time when traders expect the U.S. Federal Reserve to cut interest rates to bail out the housing market and avoid a recession. Wheat prices more than doubled in the past year, increasing costs at Sara Lee Corp. and Premier Foods Plc.

``The market is in a real frenzy,'' said Tobin Gorey, commodity strategist with Commonwealth Bank of Australia Ltd. in Sydney. ``It's feeding through to the consumer.''

Higher bread prices will result when you go shopping. Global Warming is partly responsible for the current drought in Australia, thus cutting supply, while Peak Oil makes farming more expensive (oil is used to manufacture pesticides and herbicides and is used in the machinery that plants and harvests wheat).

How about a desal plant on the coast pumping irrigation-quality water inland to keep Australian wheat farms properly hydrated?

London Desal plant

BBC:

The UK's first desalination plant providing drinking water for Londoners and people in the south-east has been granted government approval.The plant in Beckton, east London, will start producing water sometime in 2009, in times of drought or low rainfall.The site will provide up to 140m litres of drinking water a day - enough for nearly one million people.

Shire protests against Desal plant

These people aren't greenies, they're Nimbys.

Another local resident, 11-year-old Jeremy Hiskins, said he was concerned about the effects of the plant on Botany Bay.

"The whales will die and we won't be able to fish anymore."