Cloaca Maxima
The Cloaca Maxima, the main sewage system of Ancient Rome, is among the earliest sewers in the world. Its name is tied to Cloacina, a Roman goddess. The British writer Henry James later described what the place gave him: "the deepest and grimmest impression of antiquity I have ever received." That is a striking reaction to a drain. Yet the Romans themselves treated it as something close to a monument. This documentary asks who first built it, and why a marsh demanded it. It asks how a channel for waste became an emblem of Roman engineering. And it asks what became of the Cloaca Maxima once the empire that dug it was gone.
Tradition places the first works around 600 BC, under Tarquinius Priscus, the king of Rome. He is said to have ordered Etruscan workers and the plebeians to build the drain.
The ground itself was the first problem. Before any channel was dug, Priscus and his son Tarquinius Superbus set out to turn the swampy land beside the Roman forum into solid building ground. They reclaimed the Velabrum by filling it with between 10,000 and 20,000 cubic meters of soil, gravel, and debris.
The earliest drain looked nothing like a tunnel. It began as open-air channels lined with bricks and arranged around a main pipe, and it may have had no roof at all. Holes for wooden timbers appear throughout the structure. They might point to wooden bridges that served as a cover. They might equally have held the scaffolding used during construction.
A different origin is also possible. The Cloaca Maxima may first have been an open drain, formed by streams from three of the neighboring hills and channeled through the main Forum to the Tiber. As building space inside the city grew more valuable, the drain was gradually roofed over. That covered ditch was about to become the city's main storm drain.
By the late Roman Republic, the drain served as the city's main storm drain, and it had grown into a system 1,600 meters long. In the second century BC, a stretch 101 meters long was covered and enlarged so that it also worked as the main urban sewer.
Pliny the Elder, writing in the late 1st century, described the early channel as "large enough to allow the passage of a wagon loaded with hay." Strabo made the very same comparison.
Agrippa renovated and rebuilt much of the sewer. Growth had its limits, though. The drain could not keep expanding at the pace of the city, so Romans often threw their waste out through other openings instead of the sewer.
From 31 BC to 192 AD, manholes gave access to the drain, and people could travel along it by canal. Marble reliefs decorated the manholes, and the canals were built from Roman concrete and flint. By the 1st century AD, the sewer was about to be joined to every major water supply the city had.
Eleven aqueducts supplied Rome with water by the 1st century AD, and all eleven were finally channeled into the drainage system. Before reaching it, that water served public baths such as the Baths of Diocletian and the Baths of Trajan. It also fed public fountains, imperial palaces, and private houses.
Quality set the order of use. The best waters were reserved for supplies people could carry off to drink. Second quality waters went to the baths, whose outfalls joined the sewer network beneath the city streets.
The constant flow of running water carried waste along and kept obstructions from building up in the drain. The path this combined flow followed runs past some of the best known landmarks in Rome.
The sewer began at the Forum Augustum and followed the natural course of the ancient suburbs, which ran between the Quirinal, Viminal, and Esquilline Hills. It passed the Forum of Nerva, the Arch of Janus, the Forum Boarium, the Basilica Aemilia, and the Forum Romanum before ending at the Velabrum.
Its outfall lay by the Ponte Rotto and the Ponte Palatino, and some of this is still visible today. The side branches all appear to be official drains. They would have served public toilets, bathhouses, and other public buildings.
Gutters collected rainwater, rubbish, and spillage. Conduits could dispense up to ten cubic meters of water per second. Builders closed the vaults with flat panels or with rocks, and a trench wall held back sediment. A flow of that size had consequences for the health of the city, some good and some bad.
Everything Romans dumped into the streets, swamps, and rivers near the city was carried by this drain out to the River Tiber. Draining the marshy ground also cut down the number of mosquitoes, which limited the spread of malaria.
The benefit was real but incomplete. Some of the water remained polluted, and many people relied on nearby water for irrigation, swimming, bathing, and drinking. Animals, including rats, could also find their way into the drain.
Despite these flaws, Roman writers spoke of the Cloaca Maxima with unusual reverence, and some may have felt it was more than a utility.
Livy, in Book 1 of The History of Rome, gave this verdict on the sewer: "Works for which the new splendor of these days has scarcely been able to produce a match." Pliny the Elder called it an engineering marvel because it had withstood floods of filthy water for centuries. Cassiodorus, a Roman senator and scholar, praised the system in his Variae.
The Romans viewed the movement of water as sacred, so the Cloaca Maxima may have carried religious meaning. It may even have been sacrosanct. Its age and its display of engineering skill may also explain the praise. It became a symbol of Roman civilization and of Roman superiority over others.
Venus, goddess of love, was the protector of the drain. A small sanctuary to Venus Cloacina, or Venus of the Drain, stood in the Forum Romanum. That admiration did not stay inside the capital.
Roman provinces imitated the model of drainage and sewers widely, especially where plentiful aqueduct water was available. Eboracum, the modern English city of York, had an especially impressive sewer. Part of it still survives, a northern echo of the channel beneath the Forum.
In the 1600s, the Cardinal Chamberlain imposed a tax on the residents of Rome to pay for the upkeep of the drain, long after the empire had fallen. By the 1800s the Cloaca Maxima had become a popular tourist attraction. From 1842 to 1852, sections of it were drained.
In 1862, the city of Rome hired Pietro Narducci, an Italian engineer, to survey and restore the parts near the Forum and the Torre dei Conti. In 1890, Otto Ludwig Richter, a German archaeologist, produced a map of the drainage. These efforts renewed public interest in sanitation.
Today the Cloaca Maxima still carries rainwater and debris away from the center of Rome, below the ancient Forum, the Velabrum, and the Forum Boarium. Its remaining passages have been connected to the modern urban drainage system, mainly to cope with backwash from the river.
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Common questions
What is the Cloaca Maxima?
The Cloaca Maxima is the main sewage system of Ancient Rome and one of the world's earliest sewers. It drained local marshes and carried waste from the city to the River Tiber.
Who built the Cloaca Maxima and when?
According to tradition, the Cloaca Maxima was first built around 600 BC under Tarquinius Priscus, the king of Rome. He is said to have ordered Etruscan workers and the plebeians to construct it.
Where did the Cloaca Maxima run through Rome?
The Cloaca Maxima began at the Forum Augustum and ran between the Quirinal, Viminal, and Esquilline Hills. It passed the Forum Boarium and the Forum Romanum, and its outfall lay by the Ponte Rotto and the Ponte Palatino.
How did the Cloaca Maxima affect health in ancient Rome?
The Cloaca Maxima drained marshy areas, which reduced mosquitoes and limited the spread of malaria. Some of its water remained polluted, though, and rats could enter the drain.
Why was the Cloaca Maxima considered sacred?
The Romans viewed the movement of water as sacred, so the Cloaca Maxima may have had religious significance. Venus Cloacina, or Venus of the Drain, had a small sanctuary in the Forum Romanum.
Is the Cloaca Maxima still in use today?
Parts of the Cloaca Maxima still drain rainwater and debris from the center of Rome. Its remaining passages have been connected to the modern urban drainage system to cope with backwash from the river.
All sources
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