Aqueducts
What is an aqueduct?
An aqueduct is a bridge-like system built to move water from one location to another. The ancient Romans were particularly famous for their aqueducts and some still stand today. The Romans didn't invent aqueducts, but they did help spawn the English word for one.
An aqueduct is a bridge-like system built to move water from one location to another. The ancient Romans were particularly famous for their aqueducts and some still stand today. The Romans didn't invent aqueducts, but they did help spawn the English word for one.
Qanāt, (Arabic) also spelled kanat, Persian karez, Berber Arabic foggara, ancient type of water-supply system, developed and still used in arid regions of the world. A qanāt taps underground mountain water sources trapped in and beneath the upper reaches of alluvial fans and channels the water downhill through a series of gently sloping tunnels, often several kilometres long, to the places where it is needed for irrigation and domestic use. The development of qanāts probably began about 2,500 or 3,000 years ago in Iran, and the technology spread eastward to Afghanistan and westward to Egypt. Although new qanāts are seldom built today, many old qanāts are still used in Iran and Afghanistan, chiefly for irrigation.
Although the Romans are considered the greatest aqueduct builders of the ancient world, qanāt systems were in use in ancient Persia, India, Egypt, and other Middle Eastern countries hundreds of years earlier. Those systems utilized tunnels tapped into hillsides that brought water for irrigation to the plains below. Somewhat closer in appearance to the classic Roman structure was a limestone aqueduct built by the Assyrians about 691 bce to bring fresh water to the city of Nineveh. Approximately two million large blocks were used to make a water channel 10 metres (30 feet) high and 275 metres (900 feet) long across a valley.
The elaborate system that served the capital of the Roman Empire remains a major engineering achievement. Over a period of 500 years—from 312 bce to 226 ce—11 aqueducts were built to bring water to Rome from as far away as 92 km (57 miles). Some of those aqueducts are still in use. Only a portion of Rome’s aqueduct system actually crossed over valleys on stone arches (50 km out of a total of about 420 km); the rest consisted of underground conduits made mostly of stone and terra-cotta pipe but also of wood, leather, lead, and bronze. Water flowed to the city by the force of gravity alone and usually went through a series of distribution tanks within the city. Rome’s famous fountains and baths were supplied in that way. Generally, water was not stored, and the excess was used to flush out sewers to aid the city’s sanitation.
Roman aqueducts were built throughout the empire, and their arches may still be seen in Greece, Italy, France, Spain, North Africa, and Asia Minor. As central authority fell apart in the 4th and 5th centuries, the systems also deteriorated. For most of the Middle Ages, aqueducts were not used in western Europe, and people returned to getting their water from wells and local rivers. Modest systems sprang up around monasteries. By the 14th century, Brugge, with a large population for the time (40,000), had developed a system utilizing one large collecting cistern from which water was pumped, using a wheel with buckets on a chain, through underground conduits to public sites.
The water supply of New York City comes from three main aqueduct systems that can deliver about 6.8 billion litres (1.8 billion gallons) of water a day from sources up to 190 km (120 miles) away. The aqueduct system in the state of California is by far the longest in the world.
The California Aqueduct conveys water about 700 km (440 miles) from the northern (wetter) part of the state into the southern (drier) part, yielding more than 2.5 billion litres (650 million gallons) of water a day.
The elaborate system that served the capital of the Roman Empire remains a major engineering achievement. Over a period of 500 years—from 312 bce to 226 ce—11 aqueducts were built to bring water to Rome from as far away as 92 km (57 miles). Some of those aqueducts are still in use. Only a portion of Rome’s aqueduct system actually crossed over valleys on stone arches (50 km out of a total of about 420 km); the rest consisted of underground conduits made mostly of stone and terra-cotta pipe but also of wood, leather, lead, and bronze. Water flowed to the city by the force of gravity alone and usually went through a series of distribution tanks within the city. Rome’s famous fountains and baths were supplied in that way. Generally, water was not stored, and the excess was used to flush out sewers to aid the city’s sanitation.
Roman aqueducts were built throughout the empire, and their arches may still be seen in Greece, Italy, France, Spain, North Africa, and Asia Minor. As central authority fell apart in the 4th and 5th centuries, the systems also deteriorated. For most of the Middle Ages, aqueducts were not used in western Europe, and people returned to getting their water from wells and local rivers. Modest systems sprang up around monasteries. By the 14th century, Brugge, with a large population for the time (40,000), had developed a system utilizing one large collecting cistern from which water was pumped, using a wheel with buckets on a chain, through underground conduits to public sites.
The water supply of New York City comes from three main aqueduct systems that can deliver about 6.8 billion litres (1.8 billion gallons) of water a day from sources up to 190 km (120 miles) away. The aqueduct system in the state of California is by far the longest in the world.
The California Aqueduct conveys water about 700 km (440 miles) from the northern (wetter) part of the state into the southern (drier) part, yielding more than 2.5 billion litres (650 million gallons) of water a day.
