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The challenge the world faces today is balancing the supply of usable water with the demands being placed on it by its various consumers.
In this section...
Many Different Consumers Unlike other resources, water has no equal substitute or alternative in most contexts. It is used in a myriad of ways, typically broken down into the following categories: - Domestic use – drinking, cooking, washing, sanitation
- Agricultural use – irrigation, livestock, harvesting and processing food, fishing
- Industrial use – manufacturing, production of goods and services
- Energy production – electricity generation, cooling of power plants
- Transportation – shipping of goods by ocean, rivers, and lakes
- Culture and Leisure – swimming, boating, tourism, hotels, religious practices
- Environment – ecosystem health, maintenance of natural systems
Within and among countries, different stakeholders place different and competing demands on freshwater resources. The needs of all these stakeholders are growing.
Population GrowthAs the world’s population has increased, not surprisingly so has the global consumption of water. Domestic consumption has predictably increased, but so has consumption in each of the other sectors of water usage listed above. More people means higher demands for food, energy, and goods and services. The thirstiest sector of the global community is agriculture, accounting for 70% of total freshwater usage in the world, most of that going to irrigation required to grow crops. Growing efficiencies in agricultural methods have increased food production, but at a cost to the water system. In the 20th Century, a Green Revolution in farming practices made it possible to feed the world’s ever growing population. - New crop strains, fertilizers, and irrigation techniques brought an exponential increase in agricultural output, defying predictions that population growth would mean widespread famine.
- Yet these new practices are highly water-intensive, and have come online without a complementary revolution in water extraction, storage, and distribution. It is estimated that up to half of all freshwater dedicated to irrigation ends up as waste or evaporation.
- With economic development has come higher meat consumption. Meat production – from feeding and slaughtering livestock to processing and packaging meat – requires an enormous amount of water. The World Economic Forum reports that a diet which includes meat requires double the amount of water to produce compared with a vegetarian diet of the same nutritional value. Global production of meat at mid-century is expected to be twice that of 2000.
With population growth and economic development have come increased industrial demands for water, especially in the energy sector. Water and energy are closely linked: - It takes an enormous amount of water to produce energy (not only hydroelectricity, but also the water required to extract, process, and deliver energy from coal, oil, and nuclear power sources).
- Energy production, in turn, generates greenhouse gases, which impact the water cycle.
So although population growth per se makes a huge difference, so do the ways in which this growing population uses water.
- A report by the World Economic Forum points out that from 1900 to 2000, the amount of freshwater withdrawn from the cycle for human use increased nine-fold at a time when the population increased by a factor of four.
Where Population Growth is ConcentratedCurrently 90% of the world’s population growth is taking place in poor countries, a trend that is expected to continue through mid-century. Poor countries or Least Developed Countries (LDCs) have the most difficulty when it comes to balancing water supply and demand. Poverty and water stress are inextricably linked. LDCs usually lack the technology and investment necessary to collect, treat, and distribute water among consumers in an efficient manner. The losers are rural households, urban informal settlements, and small farmers.- LDCs often lack the governance and regulation infrastructure to monitor and control water flows. People living in poor countries pay some of the highest prices for water anywhere in the world, contributing up to 10% of their income for water. (International standards hold that anything over 3% is unacceptable.)
- Desperation on the part of individuals in LDCs leads to unsustainable water extraction, such as over-drilling of boreholes that damage the environment and further stress the situation.
- Collecting water is a primary activity for women and children, keeping them from attending school or obtaining jobs. This only exacerbates the poverty that leads to water stress in the first place.
- Lack of sanitation infrastructure means that much water in LDCs becomes too polluted for healthy human consumption. Populations are sickened and die in numbers unheard of in the industrial world. This further holds back development.
Some of the poorest nations in the world bear the burden of being located in the driest parts of the planet. Even if these countries were able to develop the infrastructure and capacity to manage water supply and demand, they have little to work with. This is especially true in the arid regions of North and Sub-Saharan Africa and the Middle East where much of the world’s anticipated population growth will occur. Population trends in the developed world also exacerbate water stress. In the US, for example, current demographic patterns show more Americans moving to places without enough water, such as Arizona, Nevada, California, and Colorado. In addition, rural to urban migration is producing water stress. - People often think of the rural poor living in desert areas when they think of water stress, and this is certainly part of the picture. But the urban poor fare just as badly.
- Rapid urbanization has brought people to cities that cannot handle their water needs. In the growing number of megacities in the world, informal settlements such as slums and shanty towns receive little municipal help in getting the water they need and disposing of sewage. This creates its own acute experience of water stress as scarce supplies become degraded.
- A full 60% of global population growth between now and 2020 will occur in Africa and Asia; these regions’ urban populations are expected to double.
Next: Water Supply and Consumption Out of Sync
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