Aqua Appia

The Aqua Appia was the first Roman aqueduct, constructed in 312 BC by the co-censors Gaius Plautius Venox and Appius Claudius Caecus, the same Roman censor who also built the important Via Appia.

The Appia fed the city with an estimated 73,000 cubic metres of water per day.

Its source was said by Frontinus to be about 780 paces away from via Praenestina. It flowed for 16.4 km to Rome from the east and emptied into the Forum Boarium near the Porta Trigemina. Nearly all of its length before entering the city was underground, which was necessary because of the relative heights of its source and destination, and which also afforded it protection from attackers during the Samnite Wars that were underway during its construction.

After entering the hilly area of Rome, the aqueduct alternated between tunnels through the Caelian and Aventine Hills and an elevated section. A detailed modern model of ancient Rome shows the aqueduct running along the top of the Servian Wall above the Porta Capena. It dropped only 10 m over its entire length, making it a remarkable engineering achievement for its day.

The Appia ended at the Clivus Publicus at a place called Salinae below the Aventine Hill. The water was distributed to twenty reservoirs through piping. The level of the channel was too low to be able to provide water to the hills.

As Frontinus explains: "for four hundred and forty-one years from the foundation of the City, the Romans were satisfied with the use of such waters as they drew from the Tiber, from wells, or from springs...But there now run into the City: the Appian aqueduct, Old Anio, Marcia, Tepula, Julia, Virgo, Alsietina, which is also called Augusta, Claudia, New Anio". Rome's first aqueduct was in response to the growing city and population which may have suffered a prolonged drought and major sanitary issues which affected their existing water supplies.

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