Tea

Global average water footprint: 30 litres of water for one cup of tea.    

To produce 1 kg of fresh tealeaves we require 2400 litres of water.
One kg of fresh tealeaves gives 0.26 kg of made tea, so that 1 kg of made tea (black tea as we buy it in the shop) costs 9200 litres of water.
For a standard cup of tea we require 3 gram of black tea, so that a cup of tea requires 30 litres of water.
A standard cup of tea (250 ml) thus requires 120 equal-sized cups of water.

All together, the world population requires about 30 billion cubic metres of water per year in order to be able to drink tea.
This is equivalent to 4 times the annual Meuse runoff.
Most tea is produced in rain-fed areas; only a minor fraction of the world tea production comes from areas with supplementary irrigation (a practice sometimes applied at lower altitudes).
The water needs for post-harvest processing can be neglected if compared to the water needs for growing the tea plant.
The water footprint of tea thus mainly refers to rainwater use.
 
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The water needed to have the Dutch drink tea

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