{"id":5985,"date":"2017-12-26T12:29:14","date_gmt":"2017-12-26T07:29:14","guid":{"rendered":"http:\/\/www.cawater-info.net\/all_about_water\/en\/?p=5985"},"modified":"2017-12-26T14:34:33","modified_gmt":"2017-12-26T09:34:33","slug":"is-the-world-running-out-of-fresh-water","status":"publish","type":"post","link":"http:\/\/www.cawater-info.net\/all_about_water\/en\/?p=5985","title":{"rendered":"Is the world running out of fresh water?"},"content":{"rendered":"

26The next time you open a can of soft drink, consider where the water inside it came from. The H20 in an Indian can of Coca-Cola includes treated rainwater, while the contents in the Maldives may once have been seawater. The water needs to come from such different sources for a reason \u2013 it\u2019s because there is a global freshwater crisis.<\/em><\/p>\n

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Earth’s glaciers and ice caps lock away over 68% of its freshwater supply, but scientists believe climate change accounts for their recent, rapid melting<\/p><\/div>\n

Given that 70% of the Earth\u2019s surface is water, and that volume remains constant (at 1,386,000,000 cubic kilometres), how is a water shortage even possible? Well, 97.5% is seawater unfit for human consumption. And both populations and temperatures are ever-rising, meaning that the freshwater we do have is under severe pressure.<\/p>\n

Water demand globally is projected to increase\u00a0by 55% between 2000 and 2050. Much of the demand is driven by agriculture, which accounts for\u00a070% of global freshwater\u00a0use, and food production will need to grow\u00a0by 69% by 2035\u00a0to feed the growing population. Water withdrawal for energy, used for cooling power stations, is also expected to increase by over 20%. In other words, the near future presents one big freshwater drain after the next.<\/p>\n

What\u2019s more? Right now, according to\u00a0a Nasa-led study, many of the world\u2019s freshwater sources are being drained faster than they are being replenished.<\/p>\n

Of the world\u2019s major aquifers (gravel and sand-filled underground reservoirs), 21 out of 37 are receding, from India and China to the United States and France. The Ganges Basin in India is depleting, due to population and irrigation demands, by an estimated 6.31 centimetres every year. Jay Famiglietti, senior water scientist at Nasa,\u00a0has warned\u00a0that \u201cthe water table is dropping all over the world. There\u2019s not an infinite supply of water.\u201d<\/p>\n

Meanwhile, Mexico City, built on ancient lake beds, is now sinking in some areas at a rate of nine inches a year. As the city draws on the aquifer below, the effect is like drinking a milkshake through a straw. Once horizontal streets now undulate like BMX tracks. The city imports 40% of its water, and Ram\u00f3n Aguirre D\u00edaz, director of the Water System of Mexico City,\u00a0has blamed\u201cheavier, more intense rains, which mean more floods, but also more and longer droughts.\u201d<\/p>\n

Much of the same is happening in California. From 2011 to 2016, the state suffered its worst drought in 1,200 years. Its major aquifers receded at a combined rate of 16 million acre-feet per year, and\u00a0roughly 1,900 wells ran dry. Then, in the first three months of 2017, rain fell at 228% more than its normal level, thanks to climate change,\u00a0scientists say. Lake Oroville\u00a0in the northern part of the state swung from being at 41% of capacity\u00a0to\u00a0101% in just two months, causing dams to be overwhelmed and 188,000 local residents to be evacuated.<\/p>\n

Yet even when a drought ends as spectacularly as California\u2019s, the aquifers below aren\u2019t suddenly refilled. According\u00a0to Nasa\u2019s Famiglietti, it would take four years of above-average rainfall in California for that to happen. And even then, \u201cCalifornia will still be losing water [because the] state simply does not have enough water to do all the things that it wants to do.\u201d<\/p>\n

But what else could all this mean, beyond the fact that our freshwater supply could soon be very strapped?<\/p>\n

Some hypothesise that increased water shortages around the world will lead to wars. The current Syrian civil war has been cited by many, including Dr\u00a0Peter Engelke, senior Fellow at Washington-based think tank Atlantic Council, as a recent\u00a0example. \u201cBetween 2007 and 2010, Syria experienced one of the worst droughts in recorded history, the effect of which was to decimate rural communities and drive hundreds of thousands off the land and into Syria\u2019s cities, where they were marginalised,” he says.<\/p>\n

Anders\u00a0Berntell, executive director of 2030 Water Resources Group, a multi-sector water resources body, also suggests a link to Boko Haram and Al-Shabaab, whereby young people \u201crealise that, as a result of the lack of natural resources, degraded land and lack of water there are no livelihood opportunities\u2026 There is no future for them. They become easily targeted.\u201d They are more easily radicalised.<\/p>\n

All of which would predict a bleak future \u2013 but some nations have worked out solutions. And they\u2019re impressive ones that the rest of the world can learn from.<\/p>\n

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Readily available freshwater supplies are especially crucial following natural disasters, as seen here in Bangladesh, following Cyclone Sidr in 2008\u00a0<\/span><\/p><\/div>\n

For example, Australia survived its \u201cMillennium Drought\u201d from 1997 to 2009 by rapidly implementing measures that\u00a0halved business and residential water use.<\/p>\n

\u201cAustralia is the gold standard,” says Richard\u00a0Damania, global lead economist\u00a0in the\u00a0World Bank’s Water Practice, and formerly of the University of Adelaide. The key was putting a price on water and making it a tradable commodity.<\/p>\n

\u201c[Suppose] I had water, but I’m only growing wheat. Whereas you\u2019re growing grapes or something of higher value [than wheat, but don’t have water]” he explains. “Then I can sell you that water instead of irrigating my lower value crop. This way\u2026 Australia survived the Millennium Drought extraordinarily well.\u201d<\/p>\n

Another \u2018gold standard\u2019 is Israel, which views water availability as a national security issue.<\/p>\n

By recycling effluent water, including household sewage, the Shafdan Wastewater Treatment Facility near Tel Aviv supplies\u00a0approximately 140,000,000 cubic metres\u00a0of water per year for agricultural use, covering 50,000 acres of irrigated land. Over 40% of Israel\u2019s agricultural water needs are now supplied by effluent water. The waste sludge is also sent to an anaerobic digestion plant, which uses the methane as a fuel to produce renewable energy.<\/p>\n

\u201cIf Israel can do it,” says Anders\u00a0Berntell, executive director of 2030 Water Resources Group, a multi-sector water resources group, \u201ca country located in a desert, it proves that with the right technology, economic resources and political determination, you can make it happen.”<\/p>\n

Even more mind-blowing? Israel\u2019s water treatment systems recapture 86% of the water that goes down the drain \u2013 the next-best performer, Spain, recycles just 19%.<\/p>\n

Israel is also a global leader in desalination \u2013 turning seawater into potable drinking water. Over half\u00a0of Israel’s drinking water\u00a0now comes from desalination.<\/p>\n

So can the world simply desalinate its way out of the freshwater crisis? It\u2019s unlikely, says Damiane: \u201cOn average it’s about five to seven times more expensive. The energy footprint is huge, and you’ve got to do something with the salt. If you look at aerial images around the coasts of Kuwait and Dubai [areas that are highly reliant on desalination] you\u2019ll see\u00a0the havoc that is caused\u00a0to marine ecosystems.\u201d Given the costs, both economic and ecologic, \u201cit is only a boutique solution in very rich places\u201d, he says.<\/p>\n

Coca-Cola say it uses desalination at around 30 coastal plants. But Greg Koch, whose title at Coca-Cola is\u00a0senior director of Global Water Stewardship, explains: \u201cWe don’t see for us, nor for most places in the world, desalinisation as a solution\u2026 the capital costs are going to be higher than a treatment plant to treat freshwater.\u201d One tactic the company uses is, where it uses desalination currently, dumping the brine out at sea via \u201cpipes that take it away from nearshore areas”.<\/p>\n

A simpler and cheaper solution is rainwater capture. It\u2019s an old idea whose time may have come: Beneath Istanbul, Turkey,\u00a0the Basilica Cistern\u00a0built by Caesar Justinian (A.D. 527 – 565) can hold 80,000 cubic metres of rainwater. One and a half millennia on, many cities are now emulating it.<\/p>\n

Melbourne’s largest\u00a0stormwater harvesting tank\u00a0can store four million litres of partially treated water. Authorities including Kerala, Bermuda and the US Virgin Islands require all new buildings to incorporate rainwater harvesting, while Singapore meets\u00a0up to 30%\u00a0of its water needs through rainwater capture.<\/p>\n

Even in Manchester, England, where it rains\u00a0on average 12 days every month, efforts are being made to capture the rain.<\/p>\n

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Water treatment plants, like this one in Bolivia, depend on rainfall and freshwater from glaciers – both of which are threatened by climate change\u00a0<\/span><\/p><\/div>\n

Manchester Metropolitan University\u2019s Birley Campus, built in 2014 to house some 6,500 students and staff, aims to be entirely water self-sufficient through rainwater capture, waste water recycling, and a borehole into the sandstone aquifer below.<\/p>\n

Rainwater is collected in a 20,000 litre tank below the building and is used for showering and toilet flushing. John Hindley, the university\u2019s assistant director of estates, explains: \u201cThis is about the sustainable use of resources. In October we had storms that led to a lot of flooding; the University was flooded in several different buildings. These [events] aren\u2019t just one-offs anymore, so having more sustainable systems not just in consumption, but slowing down run-off, capturing it, taking pressure off the system\u2026 is becoming of increasing importance to the university and to businesses in the city.\u201d The Birley Campus water bill is 60% lower than if using water from mains.<\/p>\n

Due to cost pressures, business could be an even greater driver of water efficiency than governments. Anders\u00a0Berntell believes that “many of the big multinational companies are way ahead of governments when it comes to understanding and acting on the challenges that we are facing.\u201d At Coca-Cola, Koch agrees there is \u201ca vested interest. We just opened a $100m (\u00a379m) plant in Phnom Penh in Cambodia, a $60m (\u00a348m) plant in Bangladesh \u2013 we want those plants to be there for decades and serve a contiguous marketplace, so we have to act.” This has included installing the latest drip irrigation techniques in farms that share the same aquifers as Coca-Cola, irrespective of whether they are direct suppliers.<\/p>\n

\u201cIn most places around the world the [agriculture] irrigation techniques are pretty inefficient,” says Engelke. \u201cVery efficient irrigation techniques do exist. Thermal power sources [nuclear, coal, natural gas] require vast amounts of water for cooling. Renewables for the most part \u2013 solar and wind \u2013 do not. It all has to do with policies to encourage, incentivise, and invest.\u201d<\/p>\n

\u201cIf we want to become water-efficient societies, there are ways in which we can do it,” concludes Engelke. \u201cEither through increasing the efficiency with which every drop of water is used, or simply shifting away from water-intensive uses altogether.\u201d<\/p>\n

Whichever effective model of conserving freshwater we come up with, we need to come up with one \u2013 and sooner rather than later.<\/p>\n

Source: http:\/\/www.bbc.com\/<\/a><\/p>\n

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