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Water resource
Water resource
Any kind of water that is suited
to use by people can be thought of as a water resource. The world’s water totals 1.4 billion cu km in volume. The largest resource is the oceans, which occupy 71% of the Earth’s surface and make up 97.25% by volume of the world’s water. Although the oceans are saltwater resources, they can be used to recover their salt content, or through desalinization they can be used to provide fresh water. Seawater can also be used as cooling water in power plants.
Although fresh water represents a very small part of the total liquid water on Earth, it is a much more useful resource than the oceans because it can be used more easily for drinking, for irrigation, and by industry.
River water can, after purification, be used as a water supply. If river valleys are dammed, water can also be stored so that it can be used throughout the year for drinking, industry, irrigation, and to generate hydroelectric power (see: Dam). For those who live at some distance from a river, water has to be moved by artificial channel, or aqueduct.
Water also seeps into the ground and becomes available in water- bearing rocks called aquifers. Many aquifers are recharged in mountain regions and then carry water underground to lowland areas that have much less reliable rain. They are called artesian supplies.
Water in the form of ice covers Antarctica, Greenland, and some of the world’s mountains. Ice represents a large amount of fresh water, making up 2% of the world’s entire water resources. However, it is very difficult to use.
Increasing population means
Reservoir
Pump
Branch
Treatment plant
Main
that people need increasingly large amounts of water. In some places, for example, the southwestern United States, demand and supply are only matched by transferring large amounts of water long distances by aqueduct. The problem of finding enough water is likely to increase in the future.
Water is only a resource for many uses if it is clean. Cleaning water is expensive, and polluting water in our rivers only increases the cost of cleaning it. One of
the most significant sources of pollution has been the seeping of salt and fertilizers from irrigated soils into aquifers and rivers. Another problem occurs when sewage is not properly dealt with and seeps into river waters.
Watershed
The name used both for the boundary of a drainage basin, which divides the river basin from its neighbors, and for the whole
 Water supply—Supplying water requires a reliable, stored reserve, which is distributed via a network of pipes. Giant pumps are used to perform this task.
drainage basin.
Water supply
The supply of water to people
at home and at work. It involves storing water in reservoirs, transporting it to centers where it is needed, treating it to make sure it is clean and safe for use, and distributing it from the treatment center to homes, businesses, and farms.
We need a water-supply industry because water flows irregularly, it is not always naturally fit to drink, and it only flows in rivers and some underground rocks.
A water supply system includes: a source or sources of supply, such as a river or an aquifer; some kind
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