Moving water from one area to another:

There are many examples, from ancient times to the present, of water being delivered from its source to where it is needed by means of channels.

Indeed, gardeners of ancient times, designed their garden layouts to encompass the very purpose of channeling water as it created additional elements such as movement, sound and changes in temperature.

Water channels were an element in the design of the geometric shapes that complimented each other overall to reflect harmony and balance as well as being significant as religious symbols.

Their design had to take careful advantage of differences of height to move water from one area to another in such a manner that they blended into the landscape design that surrounded them, feed water to the plants and water features of the design and as such draw attention to the relationship between man and nature.

One form of ancient channel, known as a Qanat, is a system of water management used to provide a reliable supply of water for irrigation and human settlement in hot and semi arid areas.

The technology is known to have been developed on the Iranian plateau and also possibly on the Arabian peninsula somewhere during the 1^st millennium BC and to have spread Eastwards right into present day China and West to as far as Madrid which still receives water from a quanat to this day.

It is estimated that Afghanistan alone has more than 250 thousand kilometers of quanats that are constantly maintained by labour with all the necessary skills, typically handed down from father to son, delivering water to its inhabitants.

This method of water harvesting is also most important as it only delivers as much water that nature itself will provide with only gradual variations from wet to dry years. i.e. There is no forced removal of water such as is done when resorting to mechanical pumping methods.

On much greater scale are the extremely sophisticated aqueducts constructed by the Romans to deliver water to any large city, as well as small towns and industrial sites, in their empire. Rome has the largest concentration of aqueducts, built over a period of 500 years, that collectively supplied around one million cubic meters of water per day.

Already, at that time, Frontinus, a general, appointed in the late 1st century AD to administer the many aqueducts of Rome, discovered a discrepancy between the intake and supply of water caused by illegal pipes inserted into the channels to divert water. He would have had to resort to a time consuming process to determine this discrepancy unlike the present where the deployment of precision water meters would reveal losses in real time.

The Roman aqueducts were built vertically to extremely fine tolerances such as the Pont du Gard which only had a fall of 34cm per kilometre, descending 17m vertically over its entire length of 50 km and capable of delivering some 20 thousand cubic meters of water per day.

The volume of channeled of water delivered to the end destination depended entirely upon many factors such as catchment hydrology, rainfall, absorption, evaporation, runoff and maintenance of the channel or aqueduct.

In an effort to reduce the influence of some of the above factors, Roman aqueducts mostly ran below the ground surface which served to keep the water clean, reduce evaporation, free from disease and to protect them from enemy attack.