Natural ecosystems require water for the survival of the plants and animals that live within them. These ecosystems help to regulate water quality and quantity of water. Wetlands hold water in periods of high rainfall, slowly releasing it during dryer periods, and purify it of heavy metals and other contaminants. Forests recharge our groundwater, which can be used elsewhere for drinking or irrigation. (Bergkamp 1) Natural ecosystems can help to prevent floods, provide shelter and millions of people are able to get their food, water, and fuel from these areas. As the world population continues to expand people are overusing water and destroying many natural resources. By destroying these ecosystems, more that 3,500 species are threatened worldwide, of which 25 percent are fish and amphibians. (Bergkamp 1) Dams block the return of salmon to spawning areas. Toxic pollution and acid precipitation kill fish; toxic metals deform waterfowl; and leaching of fertilizers promotes the growth of algae in water, which reduces oxygen levels in water killing the fish. It isn't known what global warming will do to the renewable water supplies, but it may change rainfall, storm patterns and sea levels. Water is a scarce resource and it is predicted that 30 percent of the world's population will not have enough water by 2025. (Bergkamp 3)
Humans consume water, discard it, poison it and waste it without considering the consequences. Supplying enough water in the right quantity, at the right time and in the right place has always been a concern. All of life depends on water. It is as important to life as air, food and sunlight. For this reason water has always played an important role in civilizations throughout history. People can live for days without food but will not survive for very long without water. The problem with water is that there is the same amount now as there was in pre-historic times and no way to make anymore of it.
Ten thousand years ago most of the people living on the earth were nomads who traveled near rivers and lake. Hunting animals provided them with food and most often animals would be found near a water source. Several thousand years later people began to live in settled communities and water was needed for household and agricultural use. Irrigation systems were built to water crops then there wasn't enough rain, and different ways to store water were developed.
After 3000 BC water began to be used in very sophisticated ways such as baths, toilets and flower gardens. The bathrooms and toilets in Mesopotamia were designed so that wastewater ran into sewers under the streets. As the population grew slaves were used to dig wells and canals to bring water to more areas. The canals were carefully built of stone or brick and waterproofed. Covered cisterns were used to store water for use in dry spells. Unfortunately, these elaborate water systems were destroyed during wars and after the fall of the Roman Empire it took many years before any were built that came close to these standards.
In the 19th century before the Industrial Revolution most people lived in villages and small towns without danger of using up or polluting the water sources. After the Industrial Revolution there were large populations of people concentrated in cities where many water supplies were either short or polluted. Once these cities were established it was impossible to abandon them in search of a better water source so often times large quantities of water were transported hundreds of miles to supply existing cities. In many undeveloped countries a piped water supply might end up in a public outlet at the end of a street. In Britain, a century ago a single outdoor faucet supplied a whole street with water and as recently as 1920 only one-third of the houses in Britain had a toilet. (Davies 36) Today we have high standards for the quality and quantity of water supplies.
Most of the planet is water and in some parts of the world water...
Please join StudyMode to read the full document