Romans constructed large navigable aqueducts to bring a constant flow of water from distant sources into cities and towns, supplying public baths, latrines, fountains and private households. Waste water was removed by the sewage systems and released into nearby bodies of water, keeping the towns clean. Some aqueducts also served water for mining, processing, manufacturing, and agriculture.
Aqueducts moved water through gravity alone, along a slight downward gradient within conduits of stone, brick or concrete. Most were buried beneath the ground, and followed its contours. Where valleys or lowlands intervened, the conduit was carried on bridgework, or its contents fed into high-pressure lead, ceramic or stone pipes and siphoned across. Most aqueduct systems included sedimentation tanks, sluices and distribution tanks to regulate the supply at need.
First aqueduct in Rome
Rome’s first aqueduct supplied a water-fountain located at the city’s cattle-market. By the 3rd century AD, the city had eleven aqueducts. Most of the water supplied the city’s many public baths. Cities and municipalities throughout the Roman Empire emulated this model, and funded aqueducts as objects of public interest and civic pride.
Methods of aqueduct surveying and construction are given by Vitruvius in his work De Architectura (1st century BC). The general Frontinus gives more detail, in his official report on the problems, uses and abuses of Imperial Rome’s public water supply. Before their development of aqueduct technology, Romans relied on local water sources such as springs and streams, supplemented by groundwater from privately or publicly owned wells, and by seasonal rain-water drained from rooftops into storage jars and cisterns. The reliance of ancient communities of such water resources restricted their potential growth.
Rome’s aqueducts were not strictly Roman inventions as their engineers would have been familiar with the ancient, tried and tested water-management technologies of Etruscan neighbors and Greek allies. By the early Imperial era, the city’s aqueducts supported a population of over a million, and an extravagant water supply for public amenities such as baths, fountains and latrines had become a fundamental requirement for a civilized, Roman life.
Rome had several springs within its perimeter walls but its groundwater was unpalatable and water from the Tiber was unsafe to drink. The city’s demand for water had probably long exceeded its local supplies when the Aqua Appia, Rome’s first aqueduct (312 BC) was commissioned by the censor Appius Claudius Caecus as one of two publicly funded, major projects. The other was a strategic road between Rome and Capua, the first leg of the Appian Way.