Rice requires slightly more water to produce than other grains. Rice production uses almost a third of Earth's fresh water. Water outflows from rice fields through transpiration, evaporation, seepage, and percolation. It is estimated that it takes about 2,500 litres (660 US gal) of water need to be supplied to account for all of these outflows and produce 1 kilogram (2 lb 3 oz) of rice.
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