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Some of the world’s most important farming regions rely on freshwater from large underground aquifers that have filled up slowly over thousands of years. Think of the Central Valley aquifer system in California. Or the Indus basin in Pakistan and India. This groundwater is particularly valuable when rain is scarce or during droughts.

But that groundwater may not last forever. Data from NASA’s Grace satellites suggests that 13 of the world’s 37 biggest aquifers are being seriously depleted by irrigation and other uses much faster than they can be recharged by rain or runoff. And, disturbingly, we don’t even know how much water is left in these basins. That’s according to a 2015 paper in Water Resources Research.

The map below gives an overview. There were 21 major groundwater basins — in red, orange, and yellow — that lost water faster than they could be recharged between 2003 and 2013. The 16 major aquifers in blue, by contrast, gained water during that period. Click to enlarge:

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(UC Irvine/NASA)

The researchers found that 13 basins around the world — fully one-third of the total — appeared to be in serious trouble.

Eight aquifer systems could be categorized as “overstressed”: that is, there’s hardly any natural recharge to offset the water being consumed. In the direst state was the Arabian aquifer system beneath Saudi Arabia and Yemen, which provides water for 60 million people and is being depleted by irrigation for agriculture. Also in bad shape were the Indus Basin that straddles India and Pakistan and the Murzuq-Djado Basin in Africa.

Another five aquifer systems were categorized as “extremely” or “highly” stressed — they’re being replenished by some rainwater, but not nearly enough to offset withdrawals. That list includes the aquifers underneath California’s Central Valley. During California’s recent brutal, five-year drought, many farmers compensated for the lack of surface water by pumping groundwater at increasing rates. (There are few regulations around this, though California’s legislature recently passed laws that will gradually regulate groundwater withdrawals.)

The result? The basins beneath the Central Valley are being depleted, and the ground is actually sinking, which in turn means these aquifers will be able to store less water in the future. Farmers are losing a crucial buffer against both this drought, if it persists, and future droughts.

The big question: How soon until these aquifers run dry?

Here’s the other troubling bit: It’s unclear exactly when some of these stressed aquifers might be completely depleted — no one knows for sure how much water they actually contain.

In a companion paper in Water Resources Research, the researchers took stock of how little we know about these basins. In the highly stressed Northwest Sahara Aquifer System, for instance, estimates of when the system will be fully drained run anywhere from 10 years to 21,000 years. In order to get better measurements, researchers would have to drill down through many rock layers to measure how much water is there — a difficult task, but not impossible.

“We don’t actually know how much is stored in each of these aquifers. Estimates of remaining storage might vary from decades to millennia,” said Alexandra Richey, a graduate student at UC Irvine and lead author on both papers, in a press release. “In a water-scarce society, we can no longer tolerate this level of uncertainty, especially since groundwater is disappearing so rapidly.”

The researchers note that we should figure this out if we want to manage these aquifers properly — and make sure they last for many years to come. Hundreds of millions of people now rely on aquifers that are rapidly being depleted. And once they’re gone, they can’t easily be refilled.

Further reading

— Saudi Arabia squandered its groundwater and agriculture collapsed. The rest of the world should take note.

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*** Note to Readers: We at Team GNT™ believe very strongly that “Water Solutions for a thirsty Planet” can be and will be enabled by Nanotechnology. Whether those solutions come in the form of Nano Enabled Membrane Technology, Catalyst-Thermal Technology or (Yet To Be Discovered-Developed Technology) … we expect “Great Things from Small Things”! As such we always appreciate “perspective articles” such has been offered here.

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*** Re-Posted from “One-Green-Planet” ***

All of terrestrial life depends on freshwater. From densely populated cities to rural communities, farmland and forestland, and domestic and wild animals, all are in need of clean water to sustain them. Miraculously, just a small percentage of the water on earth is actually available as freshwater.

According to the U.S. Geological Service, only about 2.5 percent of all the water on planet earth is freshwater. And only 1.2 percent of that is most easily accessible on the earth’s surface in the form of lakes, rivers, swamps, soil moisture, and permafrost. An additional 30.1 percent exists as groundwater while the majority of this freshwater, 68.7 percent to be exact, is locked up as frozen glaciers and ice caps.

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 If you’re reading into the numbers, it would appear that the majority of freshwater is not easily accessible to us for human use. And, unfortunately, many human activities are causing harm to the natural water cycle that’s in place, making freshwater resources even more difficult to access and utilize. Building impervious structures such as buildings and paved roads makes it difficult for precipitation to be absorbed by the land to replenish groundwater resources. We also impact not only the natural flow of water with barriers like dams, but also the composition and safety of water with our pollution. We are often too aggressive in harvesting water from groundwater and surface supplies, depleting underground reserves as well as rivers and lakes.  And our contributions to climate change have impacted precipitation and evaporation rates, making the resource even more unstable and less predictable.

It is in our best interest to treat freshwater supplies with the utmost respect, and yet we’re losing out on this invaluable resource due to our own ignorance and negligence.

So, what can we do to save our water? There are, luckily, a variety of solutions. From education and conservation to emerging technologies, we are hatching up a plethora of solutions to our water woes. One of the strategies that many countries are using is desalination where salt water is essentially converted into freshwater. There’s plenty of salt water on the planet, as we know, so this sounds like a fabulous idea. Or is it?

Getting freshwater From Saltwater – How?

Desalination is a process that converts salt water to freshwater by removing salts and other minerals, leaving behind freshwater, potable water. While there are a variety of methods to accomplish this task, they can be grouped mainly into two types.

The first method, thermal desalination, involves the heating of saline water. Salts are left behind while freshwater is converted to steam and is collected, ultimately to condense back into water that is now saline-free and ready for use in an instance where freshwater is desired.

The second type of desalination involves the use of membranes to separate salt and other minerals from water. Pressure or electric currents may be used to drive saline water through a membrane which acts as a filter. Freshwater ends up on one side of the membrane while saline water stays on the other side as a form of waste.

Of course, these are very, very basic descriptions of some pretty complex and evolving technologies. But they do offer a quick insight into what the process of desalination looks like in most settings around the world. For some individuals, this is the technology used to provide them with clean drinking water.

Where Are Desalination Plants Working Now?

Desalination is a technology that has been around for quite some time and is seeing improved growth around the world in the face of increasing water demands. Since 2003, Saudi Arabia, the United Arab Emirates and Spain have led the world in desalination capacities. As of 2013, there were over 17,000 desalination plants worldwide in roughly 150 countries, providing more than 300 million people with at least some of their daily freshwater needs.

Israel is one successful case-study when it comes to the value of desalination. The nation currently has a quarter of its freshwater needs met through four desalination plants that treat mainly brackish well water (water that is part salt/part fresh). Israel’s desalination plants currently produce 130 million gallons of potable water a year and they are aiming to increase that number to 200 million gallons a year by 2020. While aggressive conservation efforts also helped ease the impact of severe drought, desalination has certainly been an important piece of solving a water crises.

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Singapore is another interesting story when it comes to desalination. The country is currently pushing to improve its desalination capacity in order to gain independence in its freshwater resources. Right now it depends heavily on neighboring Malaysia to import clean water. For Singapore, desalination offers the country the chance to provide citizens freshwater even where saline water sources are much more available, ultimately becoming more independent and self-reliable.

As countries all over the world increase their capacity for desalination plants, drought-stricken areas like the United States southwest are taking note and investing in this technology. In fact, construction on the Western hemisphere’s largest desalination plant is nearly complete in San Diego, California and is expected to open for operation later this year. In the face of severe drought, desalination is becoming a much more appetizing option for this region to put its plentiful access to seawater to good use and to alleviate some of the pressures that developed and agricultural areas are placing on freshwater sources.

Is This The Answer to Water Shortages Worldwide?

Whether or not desalination is the savior for water woes is a complex debate and answers will probably vary depending on who you are asking. You’ll find there are activists, scientists, public agencies, governments, and citizens on both sides of the debate.

Ecological Impact

The first input that comes to mind when you think of desalination is probably the saline water that’s being treated, right? Depending on the source of this saline water, there may be a variety of detrimental impacts to the local ecology to consider when it comes to desalination operations.

Some desalination plants use direct intake methods to gather saline water, meaning they extract water directly from the water column, either from the surface or at greater depths in the ocean. The problem with this extraction method is that, in addition to taking in saltwater that can become a viable freshwater source, a host of marine life is also sucked up in the process. Algae, plankton, jellyfish, fish, and larva of many species can all easily be killed with this direct intake method for harvesting sea water.

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The impact of ocean water extraction on local marine life is not well understood, however, experts will note there are a variety of ways to skate around issues like this. One such method is indirect intake where pipes are buried in the substrate and intake water that is actually filtered down through the sand first. Marine life damage is largely eliminated using this method. Physical barriers to intake pipes may also be utilized where screens or meshes are able to keep smaller marine creatures out of the intake pipes. And behavioral deterrents, like bubble screens and strobe lights, are another option to discourage marine animals from swimming too close to intake systems where they become trapped.

Saline water that is being harvested for desalination projects are not the only issue creating ecological impacts for this water treatment system. The output of wastewater is another issue that critics point out when it comes to desalination. Water discharged from desalination plants has a higher level of saline than the body of water it is entering. While some creatures can tolerate change in salinity, others cannot and may be killed on contact. Discharging water that has been heated in the desalination process can also cause temperature spikes and stress to any aquatic life in a close radius. And, the water discharged from desalination operations may also have an altered chemical composition given the added antifouling agents, heavy metals, chlorine, antiscaling chemicals, and cleaning solutions used in the process. All have a potential to detrimentally impact the local ecology surrounding a desalination operation.

Some solutions for wastewater from desalination operations already exist. Because saline water is more likely to sink and move along the ocean bottom, discharging it upward can help promote mixing of wastewater more quickly to disperse salinity and weaken the impacts that concentrated salt levels can cause. Additionally, plants can invest in technology to lessen the amount of chemicals they use in the treatment process, and even attempt to let wastewater evaporate, leaving behind only solid waste for plant operators to dispose of. These may not be perfect solutions, but they are attempts to make desalination operations more friendly to the local ecology.

Energy Requirements

One major difficulty with fully embracing desalination has to do with the major energy inputs the technology requires. Costs attributed to desalination depend largely on energy costs which can and do fluctuate from year to year. Roughly 60 percent of the cost of operating a thermal desalination plant comes from the energy costs to operate the plant, while 36 percent of the cost to run a reverse osmosis plant comes from the energy it uses.

Greenhouse gas emissions associated with desalination plants depend heavily on the type of energy utilized. In an area where fossil fuels are burned to make electricity, emissions associated with desalination will be higher. Additionally, if a desalination plant relies heavily on hydroelectric power, a drought in the area may increase the cost of energy from the electric plant and thus the cost to run the desalination plant.

Money

As with any new and growing technology, there can be an expected higher cost than the conventional way of doing things. Desalination is no exception. Using San Diego County as an example, we can see just how much more expensive desalination is than other methods of providing freshwater. The cost to save an acre-foot of water through conservation and user education around efficiency may fall anywhere between $150 and $,1000. Importing an acre-foot of water may cost somewhere between $875 and $975. Recycling an acre-foot of potable water has a range in cost between $1,200 and $1,800. And providing an acre-foot of freshwater through seawater desalination would cost between $1,800 and $2,800. As local agencies and governments come up against budget cuts and financing difficulties, it may be impossible to justify this technology in the face of cheaper options that provide the same results.

Citizens will see an increase in their water bill as more of their freshwater is sourced from expensive desalination processes. This rise in basic living costs in the face of economic hardship may be difficult to justify, especially for a resource as important as freshwater. Desalination is certainly not a cost-saving choice.

Is It A Go?

It is certainly important to note the improvements that technology like desalination can provide to society. Especially as we are faced with increased challenges to meet the needs of a growing population, it is important to have a variety of options available to us.

While desalination is certainly an amazing option to convert water that was once too salty for human-use into something that can quench thirsts, maintain sanitation, and irrigate agriculture, one may be left wondering if the cost is really worth it. There are still many improvements left to be made to make this a more environmentally friendly option. As it stands, it is not without some major drawbacks when it comes to local ecology destruction, energy use, and greenhouse gas emissions. And it is certainly a very expensive option when you consider how little money it would take to simply educate the masses on how to conserve water.

Desalination is a wonderful testament to the human mind and inventive capacity, but it may simply be a very advanced and expensive method for maintaining our ignorance to the natural world with exist within. We may be able to provide freshwater in places where it didn’t previously exist, but what’s the point if people continue to remain ignorant to how to better use the water we already have? In the face of a crisis this may certainly be a valuable technology, but we have not even yet begun to address some of the issues that are causing our water shortages in the first place. And that’s an issue we need to work out through education and conversation around sustainability rather than throwing money into more expensive technology.

Lead Image Source: JohnKay/Flickr

Penn St Water M id40923 A synthetic membrane that self assembles and is easily produced may lead to better gas separation, water purification, drug delivery and DNA recognition, according to an international team of researchers. This biomimetic membrane is composed of lipids — fat molecules — and protein-appended molecules that form water channels that transfer water at the rate of natural membranes, and self-assembles into 2-dimensional structures with parallel channels.

“Nature does things very efficiently and transport proteins are amazing machines present in biological membranes,” said Manish Kumar, assistant professor of chemical engineering, Penn State. “They have functions that are hard to replicate in synthetic systems.”
The researchers developed a second-generation synthetic water channel that improves on earlier attempts to mimic aquaporins – natural water channel proteins — by being more stable and easier to manufacture. The peptide-appended pillar[5]arenes (PAP) are also more easily produced and aligned than carbon nanotubes, another material under investigation for membrane separation. Kumar and co-authors report their development in a recent issue of the Proceedings of the National Academy of Science (“Highly permeable artificial water channels that can self-assemble into two-dimensional arrays”).

 

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An artificial analogue of the water channel protein, aquaporin, was shown to have permeabilities approaching that of aquaporins and carbon nanotubes. They also arrange in tight two dimensional arrays. (Image: Karl Decker / University of Illinois at Urbana-Champaign, and Yuexiao Shen / Penn State)

“We were surprised to see transport rates approaching the ‘holy grail’ number of a billion water molecules per channel per second,” said Kumar. “We also found that these artificial channels like to associate with each other in a membrane to make 2-dimentional arrays with a very high pore density.”
The researchers consider that the PAP membranes are an order of magnitude better than the first-generation artificial water channels reported to date. The propensity for these channels to automatically form densely packed arrays leads to a variety of engineering applications.
“The most obvious use of these channels is perhaps to make highly efficient water purification membranes,” said Kumar.
Source: Penn State

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Engineered carbon nanotube membranes may help solve our growing demand for desalination.

Of course, you can’t just drink a glass of water straight from the sea. But it is possible to use water from the ocean once the salts are removed. In fact, desalination plants already provide much of the water used by people in many parts of the world, especially in Israel, Saudi Arabia, and Australia.

Climate change is only increasing the demand for desalinated water as greater evaporation and rising seas further limit freshwater supplies for a growing world population. But desalinating water today comes at a very high cost in terms of energy, which means more greenhouse gases and more global warming.

Researchers from the University of Malaya’s Nanotechnology and Catalysis Research Center in Kuala Lumpur in Malaysia say in the journal Desalination that carbon nanotube (CNT) membranes have a bright future in helping the world’s population meet the need for purified water from the sea.

“Currently, about 400 million people are using desalinated water and it has been projected that by 2025, 14 percent of the global population will be forced to use sea water,” said Md. Eaqub Ali, corresponding author of the paper presenting the current problems and future challenges in water treatments.

Existing desalination plants rely on reverse osmosis, vacuum distillation, or a combination of the two, he explained. But those methods are energy intensive, and that’s where the potential for carbon nanotube membranes comes in.

Carbon nanotubes are teeny tiny hexagonal tubes, made by rolling sheets of graphene, said Rasel Das, first author of the paper. They require little energy and can be designed to specifically reject or remove not only salt, but also common pollutants.

“The hollow pores of the CNTs are extremely, extremely tiny,” Ali said. “However, because of their amazing chemical and physical properties, they allow frictionless passes of water through the pores, but reject most salts, ions, and pollutants, giving us purified water, probably in its best form.” An array of carbon nanotubes (red) forming a membrane that is highly permeable to water (blue surface), but not sodium (yellow) and chloride (green) ions.Carbon Nanotube 072515 II Figure_1

That frictionless property is what gives CNTs the potential to purify water with so little energy. And carbon nanotube membranes come with other perks, Das added, including self-cleaning properties.

“What makes CNTs special is that they have cytotoxic properties,” he said. That means that the membranes naturally kill microbes that might otherwise foul up their surfaces. As a result, carbon nanotube membranes have the potential to last longer much longer than those in use today.

There are hurdles yet to overcome, co-author of the paper Sharifah Bee Abd Hamid said. The CNT membranes themselves are now costly to produce, especially for large-scale uses. Research is also needed to produce the membranes with pores of a more uniform distribution and size.

“Most progress in desalination research is focused on demonstrating the capability of CNT membranes at a small scale,” she said.

For larger scale operations, work is needed to produce CNT membranes on thin films or fiber cloth composites. Getting CNT membranes ready for use will require effort on material design, operational requirements, and more.

If someday, these membranes can be put to use in water-filtering pitchers or bottles, “to directly treat salty water at point of use,” Hamid says, “it is a dream come true for many.”

Did you know?

Only 2 percent of the water on Earth comes in the form of freshwater. Of that 2 percent, 70 percent is snow and ice, 30 percent is hidden underground, and less than 0.5 percent is found in surface waters including lakes, ponds and rivers.

Graphene Water 071115 RTRDE3R1-628x330 This post is part of a series examining the connections between nanotechnology and the top 10 trends facing the world, as described in the Outlook on the Global Agenda 2015. All authors are members of the Global Agenda Council on Nanotechnology.

In the 2015 World Economic Forum’s Global Risks Report survey participants ranked Water Crises as the biggest of all risks, higher than Weapons of Mass Destruction, Interstate Conflict and the Spread of Infectious Diseases (pandemics). Our dependence on the availability of fresh water is well documented, and the United Nations World Water Development Report 2015 highlights a 40% global shortfall between forecast water demand and available supply within the next fifteen years. Agriculture accounts for much of the demand, up to 90% in most of the world’s least-developed countries, and there is a clear relationship between water availability, health, food production and the potential for civil unrest or interstate conflict.

The looming crisis is not limited to water for drinking or agriculture. Heavy metals from urban pollution are finding their way into the aquatic ecosystem, as are drug residues and nitrates from fertilizer use that can result in massive algal blooms. To date, there has been little to stop this accretion of pollutants and in closed systems such as lakes these pollutants are being concentrated with unknown long term effects.

While current solutions such as reverse osmosis exist, and are widely used in the water desalination of seawater, the water they produce is expensive. This is because high pressures are required to force the waster through a membrane and maintaining this pressure requires around 2kWh for every cubic meter of water. While this is less of an issue for countries with cheap energy, it puts the technology beyond the reach of most of the world’s population.

Any new solution for water issues needs to be able to demonstrate precise control over pore sizes, be highly resistant to fouling and significantly reduce energy use, a mere 10% won’t make a difference. Nanotechnology has long been seen as a potential solution. Our ability to manipulate matter on the scale of a few atoms allows scientists to work at the same scale as mot of the materials that need to be removed from water — salts, metal ions, emulsified oil droplets or nitrates. In theory then it should be a simple matter of creating a structure with the correct size nanoscale pores and building a better filter.

Ten years ago, following discussions with former Israeli Prime Minister Shimon Peres, I organised a conference in Amsterdam called Nanowater to look at how nanotechnology could address global water issues. While the meeting raised many interesting points, and many companies proposed potential solutions, there was little subsequent progress.

Rather than a simple mix of one or two contaminants, most real world water can contain hundreds of different materials, and pollutants like heavy metals may be in the form of metal ions that can be removed, but are equally likely to be bound to other larger pieces of organic matter which cannot be simply filtered through nanopores.  In fact the biggest obstacle to using nanotechnology in water treatment is the simple fact that small holes are easily blocked, and susceptibility to fouling means that

Fortunately some recent developments in the ‘wonder material’ graphene may change the economics of water. One of the major challenges in the commercialisation of graphene is the ability to create large areas of defect-free material that would be suitable for displays or electronics, and this is a major research topic in Europe where the European Commission is funding graphene research to the tune of a billion euros. Simultaneously there are vast efforts inside organisations such as Samsung and IBM. While defects are not wanted for electronic applications, recent research by Nobel Prize winner Andrei Geim and Rahul Nair has indicated that in graphene oxide they result in a barrier that is highly impermeable to everything except water vapour. However, precisely controlling the pore size can be difficult.

Another approach taken by researchers at MIT involves bombarding graphene sheets with beams of gallium ions to create weak spots and then etching them to create more precisely controlled pore sizes. A similar approach to water transport through defects has been taken by researchers at Penn State University.

While all of the above show that graphene has prospects for use as a filter medium, what about the usual limiting issue, membrane fouling? Fortunately another property of graphene is that it can be hydrophilic, it repels water, and protein absorption has been reported to have been reduced by over 70% in bioreactor tests. Many other groups are working on the use of graphene oxide and graphene nanoplatelets as an anti-fouling coating.

While the graphene applications discussed so far address one or two of the issues, it seems that thin films of graphene oxide may be able to provide the whole solution. Miao Yu and his team at the University of South Carolina have fabricated membranes that deliver very high flux and do not foul. Fabrication is handled by adding a thin layer of graphene to an existing membrane, as distinct from creating a membrane out of graphene, something which is far harder to do and almost impossible to scale up.

Getting a high flux is crucial to desalination applications where up to 50% of water costs are caused by pressurising water for transmission through a membrane.  Performance tests reveal around 100% membrane recovery simply by surface water flushing and pure water flux rates (the amount of water that the membrane transmits) are two orders of magnitude higher than conventional membranes. This is the result of the spacing between the graphene plates that allows the passage of water molecules via nanoscale capillary action but not contaminants.Graphene Desalinate 0422 water

Non-fouling is crucial for all applications, and especially in oil/water separation as most of what is pumped out of oil wells is water mixed with a little oil.

According to G2O Water, the UK company commercialising Yu’s technology, the increased flux rates are expected to translate directly into energy savings of up to 90% for seawater desalination. Energy savings on that scale have the potential to change the economics of desalination with smaller plants powered by renewable energy and addressing community needs replacing the power hungry desalination behemoths currently under construction such as the Carlsbad Project. This opens the possibility of low-cost water in areas of the world where desalination is currently too expensive or there is insufficient demand to justify large scale infrastructure.

While more work is required to build a robust and cost-effective filtration system, the new ability to align sheets of graphene so that water but nothing else is transmitted may be the simple game-changer that allows the world to finally address the growing water crisis.

Author: Tim Harper is Chief Executive Officer of G2O Water.

Image: The colors of Fall can be seen reflected in a waterfall along the Blackberry River in Canaan, Connecticut REUTERS/Jessica Rinaldi

UN World Water Crisis 070615 1386965848_png_CROP_promovar-mediumlarge Nearly 800 million people worldwide don’t have access to safe drinking water, and some 2.5 billion people live in precariously unsanitary conditions, according to the Centers for Disease Control and Prevention.

Together, unsafe drinking water and the inadequate supply of water for hygiene purposes contribute to almost 90% of all deaths from diarrheal diseases — and effective water sanitation interventions are still challenging scientists and engineers.

A new study published in Nature Nanotechnology proposes a novel nanotechnology-based strategy to improve water filtration. The research project involves the minute vibrations of carbon nanotubes called “phonons,” which greatly enhance the diffusion of water through sanitation filters. The project was the joint effort of a Tsinghua University-Tel Aviv University research team and was led by Prof. Quanshui Zheng of the Tsinghua Center for Nano and Micro Mechanics and Prof. Michael Urbakh of the TAU School of Chemistry, both of the TAU-Tsinghua XIN Center, in collaboration with Prof. Francois Grey of the University of Geneva.

Shake, rattle, and roll

“We’ve discovered that very small vibrations help materials, whether wet or dry, slide more smoothly past each other,” said Prof. Urbakh. “Through phonon oscillations — vibrations of water-carrying nanotubes — water transport can be enhanced, and sanitation and desalination improved. Water filtration systems require a lot of energy due to friction at the nano-level. With these oscillations, however, we witnessed three times the efficiency of water transport, and, of course, a great deal of energy saved.”

The research team managed to demonstrate how, under the right conditions, such vibrations produce a 300% improvement in the rate of water diffusion by using computers to simulate the flow of water molecules flowing through nanotubes. The results have important implications for desalination processes and energy conservation, e.g. improving the energy efficiency for desalination using reverse osmosis membranes with pores at the nanoscale level, or energy conservation, e.g. membranes with boron nitride nanotubes.

Crowdsourcing the solution

The project, initiated by IBM’s World Community Grid, was an experiment in crowdsourced computing — carried out by over 150,000 volunteers who contributed their own computing power to the research.

“Our project won the privilege of using IBM’s world community grid, an open platform of users from all around the world, to run our program and obtain precise results,” said Prof. Urbakh. “This was the first project of this kind in Israel, and we could never have managed with just four students in the lab. We would have required the equivalent of nearly 40,000 years of processing power on a single computer. Instead we had the benefit of some 150,000 computing volunteers from all around the world, who downloaded and ran the project on their laptops and desktop computers.

“Crowdsourced computing is playing an increasingly major role in scientific breakthroughs,” Prof. Urbakh continued. “As our research shows, the range of questions that can benefit from public participation is growing all the time.”

The computer simulations were designed by Ming Ma, who graduated from Tsinghua University and is doing his postdoctoral research in Prof. Urbakh’s group at TAU. Ming catalyzed the international collaboration. “The students from Tsinghua are remarkable. The project represents the very positive cooperation between the two universities, which is taking place at XIN and because of XIN,” said Prof. Urbakh.

Other partners in this international project include researchers at the London Centre for Nanotechnology of University College London; the University of Geneva; the University of Sydney and Monash University in Australia; and the Xi’an Jiaotong University in China. The researchers are currently in discussions with companies interested in harnessing the oscillation know-how for various commercial projects.


Story Source:

The above post is reprinted from materials provided by American Friends of Tel Aviv University. Note: Materials may be edited for content and length.

GNT Thumbnail Alt 3 2015-page-001“Imagine getting fire-hose volumes and velocities out of your garden hose. Nanotechnology could fundamentally change the economics of desalination.”

Nearly three-quarters of the Earth’s surface is covered by water, but according to the United Nations, more than 97 percent of it is saltwater unsuited for human consumption or agriculture.

The United Nations Population Fund reports that by 2025 two-thirds of the world’s projected population of 7.9 billion may live in areas where access to safe water is limited. “Every time we add a person, it’s not just the water that person consumes but also the additional water for agriculture and industry that you have to use,” says Earl Jones, director of water-scarcity solutions in General Electric Co.’s (GE) Water & Process Technologies unit.

UN World Water Crisis 070615 1386965848_png_CROP_promovar-mediumlarge

The removal of salt from seawater is an increasingly cost effective answer to the earth’s growing clean-water needs. By 2025, two-thirds of the world’s population may live in areas where access to safe water is limited, reports the U.N.

The removal of salt from water is emerging as one of the best solutions to the world’s water problem, analysts say. According to GOLDMAN SACH S Group Inc. (GS), desalination is a $5 billion global market, with growth of 10 percent to 15 percent a year. Water Desalination Report, a trade journal, reports that more than 12,000 desalination plants are operating World-wide, with 53 percent of the world’s desalination capacity in the Middle East.

“Today, the global capacity is about 40 million cubic meters of desalinated water per day,” says Antoine Frérot, CEO of Veolia Water, the water division of Veolia Environnement (VE). “By 2015, it will be around 70 million cubic meters per day.” Improvements in two technologies are making desalination more cost-efficient, say the experts:

The thermal process, which couples a thermal desalination plant with a power plant to provide the energy, involves evaporating water to remove salt.

Reverse osmosis, the other process, uses semipermeable membranes. About 84 percent of the world’s thermal desalination capacity, which requires more energy than reverse-osmosis facilities, is located in the Middle East, according to Water Desalination Report.  

Ashkelon Desal onearth_creattica_desalination-process 2

“We have one huge advantage in the Gulf,” says Phil Cox, CEO of International Power PLC (IPR), which builds, owns and operates thermal desalination plants in that region. “The price of natural gas is extremely low here compared with the rest of the world,” he adds. Outside the Middle East, reverse osmosis is the less expensive alternative, says Jean-Louis Chaussade, CEO of Suez Environment, a unit of Suez SA (SZE). “At our biggest reverse osmosis plants, we operate at roughly 60 cents per cubic meter of use,” says Chaussade.

Aside from GE, International Power, Suez and Veolia, other companies that construct, own and/or operate desalination systems worldwide include The AE S Corp. (AES), Crane Co.’s (CR) Crane Environmental, Siemens AG’s (SI) Power Generation unit and ITT Corp. (ITT). ABB Ltd . (ABB) provides electrical systems for desalination plants, and Met-Pro Corp.’s (MPR) Fybroc division manufactures pumps used in reverse-osmosis plants.

The motivation is there to solve the world’s water needs, the companies say. “According to the U.N., the No. 1 cause of death and illness in developing nations is waterborne diseases,” says GE’s Jones. “We have the technology to fix these problems. It’s very easy to get motivated because of the great opportunity to do good.”  

The Scale Effect  

The world’s largest reverse-osmosis plant in terms of production is Veolia Water’s Ashkelon Seawater Desalination Plant (see illustration) south of Tel Aviv, which has a daily capacity of 320,000 cubic meters per day, according to the company. The plant produces enough water to meet the needs of 15 percent of Israeli households, Veolia reports. “There is a scale effect,” says Veolia Water CEO Antoine Frérot. “At a small desalination plant, the price of water is around $2 per cubic meter. In Ashkelon, the price is 55 cents per cubic meter.”

Other big projects are in the works: General Electric Co.’s (GE) Infrastructure, Water & Process Technologies reports that it plans to open Africa’s largest seawater desalination project in Algiers, Algeria. An international consortium led by Siemens’ Power Generation unit says it plans to build the world’s largest independent water and power project in Riyadh, Saudi Arabia. Uwe Rokossa, Siemens projects sales director for new plants and services in the Middle East predicts: “We will see a continuation of big power and desalination projects.”

Steam Power and Hybrids

Thermal desalination requires steam to boil seawater, GE explains. According to GE’s Earl Jones, the most widely used thermal process is called multistage flash, which heats seawater in a brine tank, immediately converting it to steam. The resulting salt-free steam is captured, cooled and condensed, creating desalinated water, Jones reports. Since only some of the seawater is converted to steam, the process is repeated multiple times in different receptacles, each time using lower atmospheric pressures. The hybrid approach, which combines thermal and reverse-osmosis processes, is an emerging technology, according to Suez Environment, which provides the reverse-osmosis part of the first-ever hybrid facility in the United Arab Emirates. Having both techniques in one plant allows for flexibility, the company says. Suez Environment reports that when demand for electricity from the thermal side’s power plant is low, priority can be given to the less-energy-intensive reverse-osmosis process.

Another form of the hybrid approach involves having a mixture of different membranes inside a reverse-osmosis pressure vessel, says Lance Johnson, senior sales and marketing manager for Dow Water Solutions. “As the water moves down the vessel, the salt concentration increases. At the tail end, where the salinity is highest, you’d have a lower-pressure membrane than at the front end to boost productivity.

Emerging “Nano-Materials” and Membranes

Mixing high and low pressure membranes in a pressure vessel can lower cost.” Applying nanotechnology to membrane science is another promising avenue, according to GE’s Jones, who notes that membranes made out of nanotubes can process water faster than older methods. “Imagine getting fire-hose volumes and velocities out of your garden hose. Nanotechnology could fundamentally change the economics of desalination.”        

Graphene Nano Membrane 071615

Read More:

Oak Ridge 1 070615 graphene-desalinate-0422-waterOakridge National Laboratory: Using New Graphene Technology to Desalinate Water

 

 

Graphene Nano Membrane 071615 Nanoscale Desalination of Seawater Through Nanoporous Graphene

 

cARBON nANOTUBE wrappingcarbCan Engineered Carbon Nanotubes Help to Avert Our Water Crisis?

*** Team GNT™ – Noteworthy as preface to this “informing article” by Mr. Frolich is that immediate solutions are going to be patchwork at best. It could be suggested that Public Policy of the last 3-plus decades , has failed horribly the citizens of California with the direction and outcomes of ‘Water Resource Policy’. We have Zero interest in debating that point.

‘And the Good News Is’ … ???? With focus being brought to bear … there are solutions for the mid and long term and we believe (Team GNT™) that “Nanotechnologies” will be at the forefront along with a directional shift in ‘Water Resource Public Policy’, in solving the looming crisis.  ***

 

water 061715 california-getty The nine cities with the worst drought conditions in the country are all located in California, which is now entering its fourth consecutive year of drought as demand for water is at an all-time high.

 

 

 

The long-term drought has already had dire consequences for the state’s agriculture sector, municipal water systems, the environment, and all other water consumers.

Based on data provided by the U.S. Drought Monitor, a collaboration between academic and government organizations, 24/7 Wall St. identified nine large U.S. urban areas that have been under persistent, serious drought conditions over the first six months of this year.

The Drought Monitor classifies drought by five levels of intensity: from D0, described as abnormally dry, to D4, described as exceptional drought. Last year, 100% of California was under at least severe drought conditions, or D2, for the first time since Drought Monitor began collecting data. It was also the first time that exceptional drought — the highest level — had been recorded in the state. This year, 100% of three urban areas in the state are in a state of exceptional drought. And 100% of all nine areas reviewed are in at least extreme drought, or D3.

According to Brad Rippey, a meteorologist with the United States Department of Agriculture (USDA), California has a Mediterranean climate in which the vast majority of precipitation falls during the six month period from October through March. In fact, more than 80% of California’s rainfall is during the cold months. As a result, “it’s very difficult to get significant changes in the drought picture during the warm season,” Rippey said. He added that even when it rains during the summer, evaporation due to high temperatures largely offsets any accumulation.

A considerable portion of California’s environmental, agricultural, and municipal water needs depends on 161 reservoirs, which are typically replenished during the winter months. As of May 31, the state’s reservoirs added less than 6.5 million acre-feet of water over the winter, 78% of the typical recharge of about 8.2 million acre-feet. A single acre-foot contains more than 325,000 gallons of water. This was the fourth consecutive year that reservoir recharge failed to breach the historical average.

1-World Water Scarcityfig1

The U.S. Drought Monitor is produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the USDA and the National Oceanic and Atmospheric Administration (NOAA). 24/7 Wall St. identified the nine urban areas with populations of 75,000 or more where the highest percentages of the land area was in a state of exceptional drought in the first six months of 2015. All data are as of the week ending June 2.

These are the nine cities running out of water.

  1. Bakersfield, CA

Exceptional drought coverage (first half of 2015):72.8%

Extreme drought coverage (first half of 2015): 100%

Population: 523,994
Over the first half of this year, nearly 73% of Bakersfield was in a state of exceptional drought, the ninth largest percentage compared with all large U.S. urban areas. The possible impacts of exceptional drought include widespread crop failures and reservoir and stream depletions, which can result in water emergencies. The drought in Bakersfield has improved somewhat from the same period last year, when nearly 90% of the area was in a state of exceptional drought — the highest in the nation at that time. Like many other areas in California, however, Bakersfield has suffered through more than four years of drought, and any improvement is likely negligible. The Isabella Reservoir on the Kern River is one of the larger reservoirs in the state with a capacity of 568,000 acre-feet. The reservoir has supplied water to Bakersfield since 1953. Today, Isabella’s water level is at less than 8% of its full capacity after falling dramatically each summer since 2011.

  1. Sacramento, CA

Exceptional drought coverage (first half of 2015): 78.3%

Extreme drought coverage (first half of 2015): 100%

Population: 1,723,634

Sacramento is the most populous city running out of water, with 1.72 million residents. The city is located just north of the Sacramento-San Joaquin River Delta, a major source of water not just for Sacramento residents but for a great deal of California. The delta also helps provide water to millions of acres of California farmland. The Sacramento and San Joaquin rivers supply nearly 80 California reservoirs. With the ongoing drought, current storage levels are well below historical averages. On average over the first half of this year, exceptional drought covered more than 78% of Sacramento. The remaining area is far from drought-free, as 100% of Sacramento was in a state of extreme drought over that period — like every other city on this list.

  1. Chico, CA

Exceptional drought coverage (first half of 2015): 85.3%

Extreme drought coverage (first half of 2015): 100%

Population: 98,176

Starting in June this year, new state legislation requires Chico residents to consume 32% less water than they did in 2013. Water bills now include water budgeting information and penalizes residents with higher fees based on how much consumption exceeds the recommended amount. The new rule may be a challenge for some residents, as Chico had among the highest per capita daily water consumption in the state in 2013, according to the ChicoER, a local news outlet. According to The Weather Channel, in April of this year a jet stream shift brought rain and snow to parts of Northern California where Chico is located, a welcome relief to the area’s long-running dry spell. Despite the short-term relief, Chico still suffers from drought — an average of more than 85% of the city was in a state of exceptional drought over the first half of this year.

  1. Lancaster-Palmdale, CA

Exceptional drought coverage (first half of 2015): 87.9%

Extreme drought coverage (first half of 2015): 100%

Population: 341,219

Compared to the first half of last year, drought conditions in Lancaster-Palmdale are worse this year. Last year, nearly 80% of the city was in extreme drought and just 10% in exceptional drought. This year, 100% of the city was classified as being in a state of extreme drought and nearly 88% in exceptional drought. Many Lancaster-Palmdale residents, particularly those in the Palmdale Water District, receive their water from the district’s water wells, the Littlerock Dam, or — like many Californians — the California Aqueduct.

The Colorado River Basin is also a major water source for the region, including Las Vegas to the northeast of Lancaster-Palmdale and Los Angeles to the southwest. Rippey explained that with only three or four wet years in over a decade, the Colorado River Basin region has endured a staggering near 15-year drought. The river, which used to flow into the ocean, now ends in Mexico. Like every other city suffering the most from drought, Lancaster-Palmdale residents are subject to various water restrictions.

  1. Yuba City, CA

Exceptional drought coverage (first half of 2015): 95.4%

Extreme drought coverage (first half of 2015): 100%

Population: 116,719

Yuba City is located on the Feather River, which runs south through Sacramento. The river begins at Lake Oroville, the site of the Oroville Dam and the source of the California Aqueduct — also known as the State Water Project (SWP). The dam’s water levels reached a record low in November 2014. While water levels have increased considerably since then, they remain at a fraction of the reservoir’s capacity. More than 95% of Yuba City was in a state of exceptional drought over the first six months of the year, making it one of only five urban areas to have exceptional drought covering more than 90% of their land area. Like other areas suffering the most from drought, the proportion of Yuba’s workforce employed in agricultural jobs is several times greater than the national proportion. The drought has had considerable economic consequences in the region. Agricultural employment dropped 30.3% from 2012 through 2013, versus the nearly 2% nationwide growth.

 

  1. Fresno, CA

Exceptional drought coverage (first half of 2015): 100%

Extreme drought coverage (first half of 2015): 100%

Population: 654,628

All of Fresno has endured at least moderate drought conditions during the first half of each year since 2012. For the first time this year, 100% of the city was in a state of exceptional drought, up from 75% in the same period in 2014, and one of only four urban areas experiencing maximum drought conditions in their entire area. Like in many parts of California and several other cities suffering the most from drought, Fresno’s economy relies heavily on agriculture. A major source of water in Fresno is groundwater pumped from aquifers, or natural underground basins. In addition, water is delivered directly from the Sierra Nevada mountains to replenish dwindling surface water levels. Precipitation over the winter was yet again disappointing, and snowpack in the Sierra Nevada mountains was measured at a record low this past April.

 

  1. Modesto, CA

Exceptional drought coverage (first half of 2015): 100%

Extreme drought coverage (first half of 2015): 100%

Population: 358,172

Like several other drought-stricken cities, Modesto is located in California’s Central Valley between the Sierra Nevada mountains and the San Joaquin River, which are both essential sources of water for the region. Lack of precipitation during the area’s multi-year drought and particularly over this past winter has resulted in record-low snowmelt levels in the mountains. In addition, the San Joaquin River supplies 34 reservoirs, which together are at 39% of their capacity as of the end of May. One of the city’s major sources of water is the Modesto Reservoir, which draws water from the Tuolumne River. The reservoir is smaller than most in California. Over the past four years, the reservoir’s water levels reached their lowest point in September 2012 and are currently just below the historical average.

  1. Merced, CA

Exceptional drought coverage (first half of 2015): 100%

Extreme drought coverage (first half of 2015): 100%

Population: 136,969

Merced is in the Central Valley, an agricultural hub, which not only accounts for a considerable portion of California’s economic output, but also supports the majority of the nation’s agricultural production. The agricultural sector in the Merced metro area accounted for 13.1% of area employment, far higher than the comparable nationwide proportion of 2%.

Agricultural businesses suffer more than perhaps any other industry during severe drought conditions. Agricultural employment shrank by 12.5% in Merced from 2012 through 2013, and the drought has only worsened since then. Over the first half of 2014, exceptional drought covered 78% of Merced, one of the highest percentages in the nation at that time. Over the same period this year, 100% of the city was at the maximum drought level.

 

  1. Hanford, CA

Exceptional drought coverage (first half of 2015): 100%

Extreme drought coverage (first half of 2015): 100%

Population: 87,941

With 100% of Hanford covered by exceptional drought conditions, the city is tied with Merced, Modesto, and Fresno for the worst drought conditions in the nation. Like the other three cities, Hanford, too, is located in the Central Valley. In addition to statewide restrictions as well as city emergency regulations already in place, city officials adopted additional water restrictions this June, such as barring serving of water at restaurants other than by request as well as vehicle and driveway washing bans. In addition to water restrictions and crop and environmental damage, the drought has impacted the region’s air quality. According to a recent report from the American Lung Association, Hanford had nearly the worst air pollution of any U.S. city. The report identified the dry, hot summers and stagnant air as key contributing factors to high concentrations of particulate matter and smog.

By Thomas C. Frohlich

 

 

water 061715 california-getty The world’s largest underground aquifers – a source of fresh water for hundreds of millions of people — are being depleted at alarming rates, according to new NASA satellite data that provides the most detailed picture yet of vital water reserves hidden under the Earth’s surface.

 

Twenty-one of the world’s 37 largest aquifers — in locations from India and China to the United States and France — have passed their sustainability tipping points, meaning more water was removed than replaced during the decade-long study period, researchers announced Tuesday. Thirteen aquifers declined at rates that put them into the most troubled category. The researchers said this indicated a long-term problem that’s likely to worsen as reliance on aquifers grows.

Scientists had long suspected that humans were taxing the world’s underground water supply, but the NASA data was the first detailed assessment to demonstrate that major aquifers were indeed struggling to keep pace with demands from agriculture, growing populations, and industries such as mining.

Satellite system flags stressed aquifers

More than half of Earth’s 37 largest aquifers are being depleted, according to gravitational data from the GRACE satellite system.

“The situation is quite critical,” said Jay Famiglietti, senior water scientist at NASA’s Jet Propulsion Laboratory in California and principal investigator of the University of California Irvine-led studies.

Underground aquifers supply 35 percent of the water used by humans worldwide. Demand is even greater in times of drought. Rain-starved California is currently tapping aquifers for 60 percent of its water use as its rivers and above-ground reservoirs dry up, a steep increase from the usual 40 percent. Some expect water from aquifers will account for virtually every drop of the state’s fresh water supply by year end.

Read more: The countries facing the worst water shortages
Lake Mead’s water level has never been lower

The aquifers under the most stress are in poor, densely populated regions, such as northwest India, Pakistan and North Africa, where alternatives are limited and water shortages could quickly lead to instability.

The researchers used NASA’s GRACE satellites to take precise measurements of the world’s groundwater aquifers. The satellites detected subtle changes in the Earth’s gravitational pull, noting where the heavier weight of water exerted a greater pull on the orbiting spacecraft. Slight changes in aquifer water levels were charted over a decade, from 2003 to 2013.

“This has really been our first chance to see how these large reservoirs change over time,” said Gordon Grant, a research hydrologist at Oregon State University, who was not involved in the studies.

But the NASA satellites could not measure the total capacity of the aquifers. The size of these tucked-away water supplies remains something of a mystery. Still, the satellite data indicated that some aquifers may be much smaller than previously believed, and most estimates of aquifer reserves have “uncertainty ranges across orders of magnitude,” according to the research.

Aquifers can take thousands of years to fill up and only slowly recharge with water from snowmelt and rains. Now, as drilling for water has taken off across the globe, the hidden water reservoirs are being stressed.

“The water table is dropping all over the world,” Famiglietti said. “There’s not an infinite supply of water.”

The health of the world’s aquifers varied widely, mostly dependent on how they were used. In Australia, for example, the Canning Basin in the country’s western end had the third-highest rate of depletion in the world. But the Great Artesian Basin to the east was among the healthiest.

Before and after pictures show the extent of California's drought (Getty)Before and after pictures show the extent of California’s drought (Getty)
The difference, the studies found, is likely attributable to heavy gold and iron ore mining and oil and gas exploration near the Canning Basin. Those are water-intensive activities.

The world’s most stressed aquifer — defined as suffering rapid depletion with little or no sign of recharging — was the Arabian Aquifer, a water source used by more than 60 million people. That was followed by the Indus Basin in India and Pakistan, then the Murzuk-Djado Basin in Libya and Niger.

California’s Central Valley Aquifer was the most troubled in the United States. It is being drained to irrigate farm fields, where drought has led to an explosion in the number of water wells being drilled. California only last year passed its first extensive groundwater regulations. But the new law could take two decades to take full effect.

©The Washington Post

 

California Water 0426 AAbtvCj      The Plan To Fix Our Aging Water Distribution System

The Problem

California homes, farms and businesses depend on water that flows from the Sierra Nevada Mountains through the state’s main water distribution system to regions across the state, including the Bay Area, Central Valley, Central Coast and Southern California. But key portions of the system are outdated and crumbling, putting the security and reliability of our local water supplies at risk. Experts warn that the system could collapse in an earthquake, and is susceptible to salt water intrusion during major droughts or natural disasters.

The Solution

The plan to fix California’s water system, known as the California Water Fix, will address the severe vulnerability in our water infrastructure and secure local water supplies. Outdated, dirt levees would be replaced with a modern water pipeline built to withstand Earthquakes and other natural disasters. Natural water flows would be restored to support the surrounding environs. The plan is critical for many California communities and our state’s economy. Learn more by scrolling down, and join our broad coalition.

Read About the Plan Here:

Californians for Water Security

1-california-drought-farms


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