Many cities originate in places where water is abundant, by rivers, lakes, or wells. "As cities grow, the water source usually becomes insufficient or even becomes too polluted for domestic use" (McDonald, 1998). Such cities have been required to construct massive aqueduct systems to carry water from another source. Aqueducts have been built all around the world, providing millions of people with the fresh clean water that they need. The construction of these aqueducts have taken a lot of time, man power, and the latest engineering techniques. The historical roles of these aqueducts have greatly affected our world socially and technologically.
Aqueduct, comes from the Latin words "aqua," meaning "water", and "ducere," meaning "to lead." An aqueduct is a structure that carries water from a source, whether it be a lake, river, or spring, to a distant city. Aqueducts may take the form of an open or enclosed canal, a tunnel, or a pipeline (Grolier, 1993).
The earliest "type" of aqueduct was the qanaat. A qanaat is a tunnel that starts at the foothill of a mountain, just below the water table, and gradually slopes downhill, to supply water to a near by city (McDonald, 1998). Qanaats were dug out of clay or cut out of solid rocks (Grolier, 1993). They were extensively used throughout the Middle East and Northern Africa (McDonald, 1998). In the city of Aleppo, Syria, drinking water still comes from a qanaat, that brings water from a spring over seven miles away (Grolier, 1993).
One of the earliest known aqueducts built above ground was the aqueduct of Jerwan. King Sennacherib of Assyria started construction on this aqueduct in 691 BC. This huge aqueduct carried water from the Greater Zab River to the king's fields and garden in Nineveh, which was over fifty miles away. A 30 foot high arched bridge was needed to support this aqueduct as it passed over a valley (Grolier, 1993). .
Another amazing aqueduct was built on the island of Samos in around 530 BC.
