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FACTS ABOUT WATER USE

Worldwide, 70% of the water that is withdrawn for human use is used for agriculture, 22% for industry and 8% is used for domestic services. In general, these proportions vary according to a country’s income: in low- and middle-income countries, 82% is used for agriculture, 10% for industry and 8% for domestic services. In high-income countries, the proportions are 30%, 59% and 11%, respectively.

It is estimated that the average person in developed countries uses 500-800 litres of water per day (300 m3 per year), compared to 60-150 litres per day (20 m3 per year) in developing countries.

In developing countries in Asia, Africa and Latin America, public water withdrawal represents just 50-100 litres per person per day. In regions with insufficient water resources, this figure may be as low as 20-60 litres per day.

At the start of the twenty-first century, agriculture is using a global average of 70% of all water withdrawals from rivers, lakes and aquifers. The Food and Agriculture Organization (FAO) anticipates a net expansion of irrigated land of some 45 million hectares in ninety-three developing countries (to a total of 242 million hectares in 2030) and projects that agricultural water withdrawals will increase by some 14% from 2000 to 2030 to meet future food production needs.

Industry impacts on water may be considered twofold:

  • Quantity: Water, often in large volumes, is required as a raw material in many industrial processes. In some cases, it may be a direct raw material, bound into the manufactured product and thus ‘exported’ and lost from the local water system when these products are sent to market. In other cases, and perhaps more commonly, water is an indirect raw material, used in washing and cooling, raising steam for energy, cooking and processing and so on. In the latter case, the wastewater may be returned to the local water system through the sewerage system or directly to watercourses.
  • Quality: Although industry requires water of good quality for manufacturing, the water it discharges may not meet the same quality standards. At best, this represents a burden on treatment plants responsible for restoring water quality to appropriate standards and suitable for recycling. At worst, industrial wastewater is discharged without treatment to open watercourses reducing the quality of larger water volumes and, in some cases, infiltrating aquifers and contaminating important groundwater resources.

Freshwater data set out in the World Development Indicators Report (World Bank, 2001) show that water for industrial use represents approximately 22% of total global freshwater use. In general, industrial use of water increases with country income, representing 59% of total water use in high-income countries but only 8% for low-income countries. The World Water Resources and their Use database forecasts that the annual water volume used by industry will rise from 752 km3/year in 1995 to an estimated 1,170 km3/year in 2025, at which time the industrial component is expected to represent about 24% of total freshwater withdrawal.

Hydropower is already a major contributor to the world’s energy balance, providing 19% of total electricity production (2,740 terawatts per hour in 2001).

Hotels and their guests consume vast quantities of water. In Israel, water use by hotels along the River Jordan is thought to contribute to the drying up of the Dead Sea, where the water level has dropped 16.4 metres since 1977.

Golf tourism has an enormous impact on water withdrawals – an eighteen-hole golf course can consume more than 2.3 million litres a day. In the Philippines, water use for tourism threatens paddy cultivation. Tourists in Grenada (Spain) generally use seven times more water than local people and this discrepancy is common in many developing tourist areas.

Information from:
World Water Development Report 'Water for People, Water for Life'
Vital Water Graphics: Water use and management section

Source: UNESCO Water Portal, May 2005