About Opentopia
Opentopia Directory Encyclopedia Tools

Aqueduct (Roman)

Encyclopedia : A : AQ : AQU : Aqueduct (Roman)

 

The ancient Romans constructed numerous aqueducts to supply water to cities and industrial sites. These aqueducts were among the greatest engineering feats of the ancient world, and set a standard not equaled for over a thousand years after the fall of Rome. Many cities still maintain and use the ancient aqueducts for their water supply even today.

The Romans typically built aqueducts to serve any large city in their empire. The city of Rome itself, being the largest city, had the largest concentration of aqueducts, with water being supplied by eleven aqueducts constructed over a period of 500 years.

Contents

Engineering

The combined length of the aqueducts in the city of Rome was nearly 260 miles (416 km). (Hodge estimates the length at a little over 500 km). However, only 29 miles (47 km) were above ground, as most Roman aqueducts ran beneath the surface of the ground. Building underground helped to keep the water free from disease (the carcasses of animals would not be able to get into the aqueduct) and helped protect the aqueducts from enemy attack. The longest Roman aqueduct, the Zaghouan Aqueduct, is 57.5 miles (92.5 km) in length. It was built in the 2nd century to supply Carthage (in modern Tunisia).

The arcades, a series of arches, popularly shown to depict an aqueduct, should not be confused with the aqueduct itself. These arches sometimes on several tiers were constructed to carry the aqueducts over unavoidable dips, such as river valleys.

Roman aqueducts were extremely sophisticated constructions. They were built to remarkably fine tolerances, and of a technological standard that had a [[wiktionary:gradient|gradient]] of only 34 cm per km (3.4:10,000), descending only 17 m vertically in its entire length of 31 miles (50 km). Powered entirely by gravity, they transported very large amounts of water very efficiently (the Pont du Gard carried 20,000 cubic meters a day and the combined aqueducts of the city of Rome supplied around 1 million cubic meters (300 million gallons) a day (an accomplishment not equalled until the late 19th century and represents a value 25% larger than the present water supply of the city of Bangalore, with a population of 6 million). Sometimes, where depressions deeper than 50 m had to be crossed, gravity pressurized pipelines called inverted siphons were used to force water uphill (although they almost always used venter bridges as well). Modern hydraulic engineers use similar techniques to enable sewers and water pipes to cross depressions.

In addition to the expertise needed to build them, Roman aqueducts required a comprehensive system of regular maintenance to repair accidental breaches, to clear the lines of debris, and to remove buildup of chemicals such as calcium carbonate that naturally occur in the water.

Construction

Many tools were used in the construction of the aqueduct. An example of this is the chorobates. The chorobates was used to level terrain before construction. It was a wooden object supported by four legs with a flat board on top; in which was engraved a half circle. When used the half circle was filled with water and the angle at which there was no water was measured. Another tool used in the construction of the aqueduct was the groma. Gromas were used to measure right angles. A groma consisted of stones hanging off four sticks perpendicular to one another. Distant objects could be marked out against the station of the stones in a horizontal plane.

Decline of the aqueducts

With the fall of the Roman Empire, although some of the aqueducts were deliberately cut by enemies, many more fell into disuse from the lack of an organized maintenance system. The lack of functioning aqueducts to deliver water had a large practical impact in reducing the population of the city of Rome from its high of over 1 million in ancient times to considerably less in the medieval era.

List of Roman aqueducts

Aqueducts in the city of Rome

In order to meet the massive water needs of its huge population, the city of Rome itself was supplied with 11 aqueducts. Their combined capacity was capable of supplying at least 1,127,220 cubic meters (nearly 300 million gallons) of water to the city each day. Detailed statistics for the city's aqueducts were logged around 97 by Sextus Julius Frontinus, the curator aquarum (superintendent of the aqueducts) for Rome during the reign of Nerva. Less information is known about aqueducts built after Frontinus.

Aqueducts in Rome
Name Year built Length
(km) 		Height at
source (m) 		Height in
Rome (m) 		Capacity
(m³ a day)
Aqua Appia 312 BC 16.561 30 20 73,000
Anio Vetus 272 - 269 BC 63.64 280 48 175,920
Aqua Marcia 144 - 140 BC 91.424 318 59 187,600
Aqua Tepula 125 BC 17.745 151 61 17,800
Aqua Julia 33 BC 21.677 350 64 48,240
Aqua Virgo 19 BC 20.697 24 20 100,160
Aqua Alsietina 2 BC ? 32.815 209 17 15,680
(not drinkable)
Aqua Claudia 38 - 52 68.681 320 67 184,280
Anio Novus 38 - 52 86.876 400 70 189,520
Aqua Traiana 109 32.500 align="center"
align="center"
align="center"
Arcus Alexandriana 226 22 align="center"
align="center"
align="center"

See also Aqueducts of Rome.

Other locations

The Romans built aqueducts in most sufficiently large cities in the Empire. Their remains (in some cases still functioning) may be found today in many places, including:

See also

External links

References

 

From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.
All text is available under the terms of the GNU Free Documentation License See Wikipedia Copyrights for details.

Search Titles
0123456789
ABCDEFGHIJ
KLMNOPQRST
UVWXYZ?

E-mail this article to:

Personal Message: