If you live in an area where ample rain falls all year, you won't see many aqueducts like the ones pictured here. But there are many areas of the world, such as the western United States, where much less rainfall occurs and it may only occur during certain times of the year.
Large cities and communities in the dry areas need lots of water, and nature doesn't always supply it to them. Some parts of the western U. So, some states have developed ways of moving water from the place of ample supply to the thirsty areas. Engineers have built aqueducts, or canals, to move water, sometimes many hundreds of miles.
Actually, aqueducts aren't a high-tech modern invention—the ancient Romans had aqueducts to bring water from the mountains above Rome, Italy to the city. Can you see something about the aqueduct picture above that causes some water to be lost in transit? In all environments, but especially In places where the climate is hot and dry, a certain portion of the water flowing in the aqueduct is bound to evaporate.
It would be more efficient to cover the aqueduct to stop loss by evaporation , but the cost of covering it must be weighed against the value of the evaporated water. The aqueduct was used to supply water to the town on Nimes, which is about 30 miles from the Mediterranean Sea. The total length of the aqueduct was about 31 miles, though, considering its winding journey. There is even a Roman aqueduct that is still functioning and bringing water to some of Rome's fountains.
The Acqua Vergine, built in 19 B. Aqueducts were not the Roman's choice for water-delivery systems, as they would use buried pipes when possible much easier to bury a pipe than build an above-ground system. To achieve a consistent, shallow slope to move the water in a continuous flow, the Romans lay underground pipes and constructed siphons throughout the landscape. Workers dug winding channels underground and created networks of water pipes to carry water from the source lake or basin into Rome.
The pipes were typically built in concrete, but were sometimes made of lead when the government provided enough cash lead was very expensive in B. When the pipes had to span a valley, they built a siphon underground: a vast dip in the land that caused the water to drop so quickly it had enough momentum to make it uphill. Siphons are part of the mechanism that makes toilets flush, too see How Toilets Work.
The problem with siphons, though, was the cost: Siphons really needed lead pipes to work effectively, since the water had to pick up speed. This led to the use of the features most of us have come to associate with Roman aqueducts: the arches. When siphons were impractical, which was often, arches were constructed to span the valley.
The pipes ran along the tops of the arches. In recent years basins have been found alongside the channel, originally built to filter out the sand carried along from its source. Unlike other aqueduct bridges, plundered for their stone, the Segovia structure has been in almost constant use since its construction, ensuring it has survived intact for nearly 2, years.
Even for Romans, private access to water came at a price. Homeowners who could afford running water paid for the service based on the diameter of their access pipe, a not entirely foolproof billing system.
There are records of homeowners slyly installing wider pipes than those for which they paid. This scam led to the invention of the calix, a sleeved pipe fitted into the wall, which was decorated to prevent forgeries or alterations.
They were also used in the castella aquarum, the tanks from which water was distributed to different parts of the city.
Despite regulation, some Romans tried to steal water from the source and would drain off water from the aqueduct or bribe the aquarii to do so. In the first century A. To such a practical people as the Romans, aqueducts were a source of great pride and even part of their identity. Frontinus made that clear in his treatise on these great public works. All rights reserved. Timeline: Bringing Water to Rome. Please be respectful of copyright.
Unauthorized use is prohibited. The Caracalla Baths, depicted in this 19th-century engraving, opened in A. Thanks to the aqueduct, free public access to baths became a highly valued privilege of Roman civic life. Digging Tunnels. A method for digging the underground section of a Roman aqueduct. Working With Geography. Speleologists carefully examine the supporting structures in the Aqua Virgo. Bridging Past and Present.
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High-ranking rulers often had them built; the Roman emperors Augustus, Caligula, and Trajan all ordered aqueducts built. The most recognizable feature of Roman aqueducts may be the bridges constructed using rounded stone arches.
Some of these can still be seen today traversing European valleys. However, these bridged structures made up only a small portion of the hundreds of kilometers of aqueducts throughout the empire.
The capital in Rome alone had around 11 aqueduct systems supplying freshwater from sources as far as 92 km away 57 miles. Despite their age, some aqueducts still function and provide modern-day Rome with water. The Aqua Virgo, an aqueduct constructed by Agrippa in 19 B. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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