ICOLD 64 pages GB
30/05/07
14:11
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The World’s Water Our lakes and rivers contain the smallest portion of our fresh water. As it rains, some of the water in these lakes flow into our streams and rivers and then the ocean. Because of the relatively small amount of freshwater available
Less than 1 % of the world’s water supply is in our lakes...
for consumption, it is essential that we manage it and do not pollute or contaminate our natural lakes and rivers. This requires waste water treatment plants and managed landfill sites for waste disposal.
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© 5 (see p.64)
... and in our rivers
How we Get Water “The World’s Water Cycle” Water
exists on earth as a solid (ice), liquid (water in the oceans, lakes and rivers) or as a gas (water vapor). The oceans, rivers, clouds and rain, all of which contain water, are in a frequent state of change (surface water evaporates, cloud water precipitates, rainfall infiltrates the ground, etc.). However, it is important to understand that the total amount of the earth's water does not change. The circulation and conservation of earth's water is called the "water cycle".
D a m s &t h e World’sWa te r
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