Water: Earth’s Most Precious Resource

Water resources are sources of water that are useful or potentially useful to humans. Uses of water include agricultural, industrial, household, recreational and environmental activities. Virtually all of these human uses require fresh water. Fresh water is a renewable resource, yet the world’s supply of clean, fresh water is steadily decreasing. While the world’s population tripled (утроилось) in the 20th century, the use of renewable water resources has grown six-fold (в шесть раз).

Table 1: Contribution to Earth’s total water resources in %

Although 70 % of the Earth is covered by seawater and a further 3 % by ice, neither of these is easily transformed into usable water.

Less than 1 % of the Earth’s total water resources is usable for drinking, farming or industry.

It is estimated that 69 % of worldwide water use is for irrigation, 22 % of worldwide water use is industrial and only 8 % of worldwide water use is for household purposes. Basic household water requirements were estimated at around 50 liters per person per day, excluding water for gardens. Drinking water is water of sufficiently high quality so that it can be consumed or used without risk of immediate or long term harm. Such water is commonly called potable water.

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