Fresh Water - Challenging Future Engineers

Bureau Built Expressions

'Big Blue Ball'- that is how our planet looks with abundant water from space. But the ground reality is entirely different. Water, in many parts of the world has become unsustainable, threatening not only local populations but global agriculture as well. Ten countries, namely, Bahrain, Qatar, Kuwait, Libya, Djibouti, United Arab Emirates, Yemen, Saudi Arabia, Oman, and Egypt are facing extreme risk. In the other parts of the world ; The northeast provinces of China, including Beijing, Jiangsu, Shandong and Tianjin; The Indian states of Haryana, Uttar Pradesh, Gujarat and Rajasthan; Parts of the US Midwest and Southwest, water is getting depleted faster than it is recharged. 

"The impacts of weather patterns on existing levels of water stress provide a vivid indication of future areas where conflict or unrest may emerge over access to water," observes Beldon. "For instance, the Argentine government's plans to increase significantly extraction of natural gas reserves through hydraulic fracturing which will require huge amounts of fresh water. Future La Niña events will compound levels of stress in agricultural and energy-producing belts, potentially creating significant tensions between users." 

The International Year of Water Cooperation 2013 is officially launched on 11 February 2013 by Michel Jarraud, Chair of UN-Water and Irina Bokova, Director-General of UNESCO and representatives from governments, local communities, specialized NGOs and UN organizations joined eminent specialists and youths to discuss:  the contribution of water cooperation to the Post-2015 Development Agenda so as to effectively address the needs of all societies, and Ways to harness cooperation at all levels to address water-related challenges, including: Regional cooperative mechanisms, Government action at the national level, Action at the local level, Cooperation at the basin level, and Science, capacity building and partnerships.

Major Threats 

The world today faces five major threats to our fresh water supplies; 

• Ageing infrastructure - Water wastage due to bursting of waterlines is cery common across the world.  Some of the water and sewer systems across the world are more than 100 years old and date back to the Civil War era.  
• Climate change - Current climate models indicate that a warmer world will also have a more intense water cycle, but that doesn't necessarily mean more rain for all regions. While some areas can expect more heavy downpours and, yes, even heavier snowfalls, the interior parts of continents will likely see more evaporation than precipitation, meaning a potential for "more severe, longer-lasting droughts." 
• Rising energy demands - As traditional oil sources become more expensive, energy companies are finding it profitable to extract petroleum from so-called "tar sands" or "oil sands." In Alberta, Canada, extracting one cubic meter of crude oil from the Athabasca deposits requires between 2 and 4.5 cubic meters of water, according to report from the Pembina Institute. Operations there are "currently licensed to divert 359 million (cubic meters) from the Athabasca River, or more than twice the volume of water required to meet the annual municipal needs of the city of Calgary." Other energy sources - including bio-fuels and thermal solar - are also water-intensive. 
• A growing global population - The world's population is expected to grow from 6.8 billion today to around 9 billion by 2050. As Peter Brabeck-Letmanthe, chairman of Nestle, notes in a commentary today, "by 2030 one third of the global population, mainly concentrated in developing countries, will have only half the amount of naturally renewed water available they need." 
• Nitrogen runoff - Nitrogen-laden runoff from agricultural regions is leading to a growth in ocean dead zones devoid of oxygen. In a study published last year, researchers warned we have already pushed past the planet's boundary of sustainability for the nitrogen cycle. (The study also identified two other areas in which we've passed tipping points: climate change and biodiversity loss.) 

Sea Water into Drinking Water

'Siemens' having completed early tests of 'an energy-saving method' for turning saltwater into clean drinking water, is preparing to take its technology to the product development phase. The technology, which uses half as much energy as other desalination processes, was tested at a demonstration plant built in Singapore. Siemens now plans to set up a full-scale system in cooperation with Singapore's national water agency PUB by 2013.Singapore, an island nation, is one of many parts of the world in which

Instead of using reverse osmosis, which requires high-pressure pumps to force water through semi-permeable membranes, the Siemens process relies on electrochemical desalination. The process combines electro-dialysis (ED) and 'Continuous-electro-de-ionization'-(CEDI), both applying an electric field to draw sodium and chloride ions across ion exchange membranes and out of the water. As the water itself does not have to pass through the membranes, the process can be run at low pressure, and hence low power consumption.

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