Harnessing Gravity: Roman Aqueducts

The Trevi Fountain, one of Rome's most spectacular sites, features the statue of Oceanus riding in a triumphal shell-shaped chariot pulled by two seahorses, each guided by a triton. As impressive as it is, the most remarkable part of the fountain is that it's the terminal point of the Aqua Vergine, the only Roman aqueduct still in operation for more than two millennia.

Trevi Fountain, Rome, Italy - Diliff, CC BY-SA 3.0

Many ancient civilizations built aqueducts, but the Roman system is the most well-known due to the sheer number and scale. The word aqueduct is derived from the Latin words aqua, meaning water, and ducre, meaning to lead. Contrary to what one may assume, the majority of aqueducts were not built to supply drinking water, as most of Rome's cities had already established a network of wells and cisterns. Aquaducts were rather regarded as luxuries, designed to supply lavish baths, ornate fountains, and the homes of the elite.

Aqua Anio Vetus, the second oldest Roman aqueduct erected (after the Aqua Appia) in 272 BCE - Alessandro, CC BY-SA 4.0

The Aqua Appia was the first Roman aqueduct. It was about ten miles long and was mostly underground. It supplied Rome with an estimated 54,750 cubic meters of water a day. Commissioned in 312 BCE, it was an early sign of the skill and ambition of Roman infrastructure projects.

The Aqua Marcia, constructed in 144-140 BCE, was the longest of the eleven aqueducts that supplied the city of Rome - trolvag, CC BY-SA 3.0

The arches of aqueducts, the sections most famous today, are simply the support structures for the downward sloping canal that allowed water to gradually flow from a hillside spring by gravity alone. The channel gradient had to be steady, with most Roman aqueducts having a descent of only 1.5 to 3.0 m/km.

Aqua Claudia was an ancient Roman aqueduct that was begun by Emperor Caligula in AD 38 and finished by Emperor Claudius in AD 52 - Erik Torner/Flickr

Roman historian Pliny described Roman Aqueducts as "the greatest wonder the world has ever seen." Still delivering to fountains today, the aqueducts are another living legacy of ancient Rome.

Works cited:

“Aqua Marcia.” Archive1.Village.virginia.edu, archive1.village.virginia.edu/spw4s/RomanForum/GoogleEarth/AK_GE/AK_HTML/AQ-004.html.

lcarroll. “What Roman Aqueducts Can Reveal | Real Archaeology.” Vassar.edu, 10 Nov. 2019, pages.vassar.edu/realarchaeology/2019/11/10/what-roman-aqueducts-can-reveal/.

“Aqueducts of Rome, Italy.” Building the World, 3 Apr. 2012, blogs.umb.edu/buildingtheworld/waterworks/aqueducts-of-rome-italy/.