Early humans

Early humans were hunter-gatherers, roaming from place to place, but their movements were controlled by the need for water. When humans started to grow food, establishing permanent settlements, water was needed for crops and animals as well as for people, so settlements have always grown up near reliable sources of water. Most major towns lie on the banks of rivers, or, where there are no streams or rivers, settlements exist where underground water can be reached by digging wells. The management of water resources has a long history. The oldest known dam in the world was constructed in Egypt about 5000 years ago, and was used for storing drinking and irrigation water. Farmers in Arabia at this time used the craters of extinct volcanoes as storage tanks for irrigation water and dug deep wells for their drinking water. Excavated ruins in India of similar antiquity retain the remains of water supply and drainage systems, which included baths and swimming pools.