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KEY FACTS ABOUT WATER
FRESHWATER IS A SCARCE RESOURCE
- Water makes up 60 to 70 per cent (by weight) of all living organisms and is essential for photosynthesis.
- The total amount of water on Earth barely changes from year to year. The hydrological cycle of evaporation and precipitation circulates the Earth’s water between the oceans, land and the atmosphere.
- Water covers 75 per cent of the Earth’s surface — 97.5 per cent of that is salt water, only 2.5 per cent is freshwater.
- Icecaps and glaciers hold 74 per cent of the world’s freshwater. Almost all the rest is deep underground, or locked in soils as moisture or permafrost. Only 0.3 per cent of the world’s freshwater is found in rivers or lakes.
- Less than one per cent of the world’s surface or below-ground freshwater is accessible for human use.
- Within 25 years, half the world’s population could have trouble finding enough freshwater for drinking and irrigation.
- Currently, over 80 countries, representing 40 per cent of the world’s people, are subject to serious water shortages. Conditions may get worse in the next 50 years as populations grow and as global warming disrupts rainfall patterns.
- A third of the world lives in water stressed areas where consumption outstrips supply. West Asia faces the greatest threat. Over 90 per cent of the region’s population is experiencing severe water stress, with water consumption exceeding 10 per cent of renewable freshwater resources.
FRESHWATER IS ESSENTIAL FOR HEALTH
- Improved water management has brought enormous benefits to people in developing countries. In the past 20 years, over 2.4 billion people have gained access to safe water supplies and 600 million to improved sanitation.
- Nevertheless, one in six people still have no regular access to safe drinking water.
- More than twice that number (2.4 billion people) lack access to adequate sanitation facilities.
- Those without access to adequate sanitation are the poorest and most vulnerable. The problem is particularly severe in remote rural and rapidly growing urban areas.
- In Africa, 300 million people—40 per cent of the population—live without basic sanitation and hygiene, an increase of 70 million since 1990.
- As much as 90 per cent of waste water in developing countries is discharged without treatment into rivers and streams.
- Unsanitary water, which provides a breeding ground for parasites, amoebas and bacteria, damages the health of 1.2 billion people a year.
- Water-borne diseases are responsible for 80 per cent of illnesses and deaths in the developing world, killing a child every eight seconds.
- Half the world’s hospital beds are occupied by people suffering from water-borne diseases.
- Almost 40 per cent of the world’s population lives within 60 kilometres of the coast. Disease and death related to polluted coastal waters alone costs the global economy US$16 billion a year.
- In southern Asia, between 1990 and 2000, 220 million people benefited from improved access to freshwater and sanitation. In the same period, the population grew by 222 million, wiping out the gains that had been made.
- During the same period, in East Africa, the number of people without sanitation doubled to 19 million.
- The cost of providing safe drinking water and proper sanitation to everyone in the world by 2025 will be US$180 billion a year, two to three times greater than present investments.
FRESHWATER IS A SHARED RESOURCE
- Rivers form a hydrological mosaic on the political map of the world.
- There are an estimated 263 international river basins, which cover 45.3 per cent of the Earth’s land surface area (excluding Antarctica) and are home to more than half the planet’s human population.
- One third of these 263 transboundary basins are shared by more than two countries.
- Rarely do watershed boundaries coincide with administrative boundaries.
- Many countries also share groundwater aquifers.
- Groundwater aquifers store as much as 98 per cent of accessible freshwater supplies. They provide 50 per cent of global drinking water, 40 per cent of industrial demands and 20 per cent of water for agriculture.
- On average, individual daily domestic use of freshwater in developed countries is 10 times more than in developing countries. In the UK the average person uses 135 litres of water every day. In the developing world the average person uses 10 litres.
FRESHWATER IS ESSENTIAL FOR FOOD SECURITY
- Most of our freshwater is used to grow food.
- While the daily drinking water needs of every person is approximately four litres, between 2,000 and 5,000 litres of water are needed to produce an individual’s daily food requirements.
- Agriculture accounts for over 80 per cent of world water consumption.
- It is estimated that between 14 and 17 per cent more water will be needed for irrigation by 2030 to feed the world’s growing population.
- Sixty per cent of water used for irrigation is wasted.
- A 10 per cent improvement in irrigation efficiency could double the drinking water supply for the poor.
- In Africa, more than 20 per cent of the population’s protein comes from freshwater fisheries.
WATER IN THE FUTURE
- Two hundred scientists in 50 countries have identified water shortage as one of the two most worrying problems for the new millennium (the other was climate change).
- Since 1950, global water use has more than tripled.
- On current trends, over the next 20 years humans will use 40 per cent more water than they do now.
- The number of people living in water-stressed countries is projected to climb from the current 470 million to three billion by 2025. Most of those people live in the developing world.
- To achieve the 2015 targets for freshwater provision, water supplies will have to reach an additional 1.5 billion people in Africa, Asia, Latin America and the Caribbean.
- Nearly 200 million people in Africa are facing serious water shortages. By 2025, nearly 230 million Africans will face water scarcity, and 460 million will be living in water-stressed countries.
- Water problems are more related to mismanagement than scarcity.
- Up to 50 per cent of urban water and 60 per cent of water used in agriculture is wasted through leaks and evaporation.
- Logging and land conversion to accommodate human demand has shrunk the world’s forests by half, contributing to increased soil erosion and water scarcity.
- Between 300 and 400 million people worldwide live close to and depend on wetlands.
- Wetlands act as highly efficient sewage treatment works, absorbing chemicals and filtering pollutants and sediments. Urban and industrial development has claimed half the world’s wetlands.
- Sustainable development and poverty alleviation will only be achieved through better management of and investment in rivers and wetlands and the lands that drain into them.
Source: World Environment Day - WED 2003
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