The participating pupils enthusiastically found the pH of a sample of water from Intaka Island (a wetland in Cape Town) and thereafter filtered and purified the water.

UNESCO: World Water Assessment Programme (WWAP)

Although primarily produced for industrial use, the water is purified to drinking-quality using dual membrane microfiltration and reverse osmosis technologies, and marketed as bottled water for human consumption under the consumer brand NEWater.

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The team also plans to build awareness within the local community about the need to drink purified water.

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Finally, the caissons on both sides will be emptied, after the water inside has been purified to protect the marine environment, and filled with air, Costa said.

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We dined in their mess hall and drank purified water from the Tigris that they bottle at the base.

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Once there, the water is filtered and purified before it is ready for use and consumption.

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The startup also plans to use the money to develop products for processing wastewater and delivering purified water for industrial operations such as oil and gas or beverage production, Green said.

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Meanwhile, rainwater would trickle down the curved exterior of the four-level home where it would be collected, then purified, for drinking water.

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More worrying still, the Ministry of International Trade and Industry has warned makers of 24-hour baths, which keep supposedly purified water hot all day, that their products may harbour Legionnaires' disease.

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