History

 

In the prehistoric times before the discovery of agriculture, humans were predominantly nomadic. They wandered from place to place in search of sufficient supplies of food and water. They camped near water sources and stayed as long as the food and water could support them. As soon as one of the resources was depleted, the people packed up their camps and moved on in search of another suitable location.

The development of agriculture in about 6500 BC solved the problem of finding sufficient food for survival. People could now abandon the nomadic lifestyle in favor of settling in one place and living there for an extended period of time. This gradual formation of permanent settlements marked the beginning of human civilization, for now a segment of the population could engage in activities other than food gathering. However, like the people themselves, successful agriculture required a plentiful source of water. Because water was so essential for agricultural practices, the first agricultural centers developed in regions with substantial water supplies. The first four known agricultural centers were in the regions of (1) the Nile River in Egypt, (2) the Tigris and Euphrates Rivers (Mesopotamia) in the Middle East, (3) the Indus and Ganges Rivers in India, and (4) the Huang He (Yellow River) in China. Human civilization was born in these regions, and water enabled it to survive.

For a description of how these early farms were irrigated, see flooding irrigation.

Because of agriculture, people were able to grow more food than they could eat. As a result of food surpluses, small settlements began to grow into villages, towns, and cities. With an increase in the number of people living in close proximity came an increase in the amount of water needed, both for drinking and for irrigation. As populations began to outgrow the water supplies of the immediate area, artificial waterways, called aqueducts, were needed to bring in new water from more remote sources.

Although much has changed in the thousands of years that have passed since the first primitive aqueducts were built, humankind's dependence upon water for survival has not. Therefore, aqueducts are still being built and used today in our modern society. For an in-depth look at how one American city built up what would become one of the largest aqueduct systems in the world, see Los Angeles: A Case Study.