Aqua Appia
The Aqua Appia was the first Roman aqueduct: 47 , and its construction was begun in 312 BC by the censor Appius Claudius Caecus: 148 : 338-9 : 23 , who also built the important Via Appia. By the end of the 1st century BC it had fallen out of use as an aqueduct, and was used as a sewer instead: 58 .
The springs feeding Via Appia were discovered by Appius' co-censor Gaius Plautius Venox, who received the cognomen Venox for the discovery: 338-9 : 23 . The aqueduct was named after Appius alone because Plautius resigned after serving 18 months as a censor: 338-9 while Appius deceitfully kept his position until the aqueduct was completed: 340-1 .
It's not certain how much water Aqua Appia fed to the city of Rome, but in the city records it is mentioned to have 841 quinariae -- 34,901 m3 (9,220,000 US gal) per 24 hours: 388-9 : 25 . However, measurements taken in the 1st century AD resulted with pipes being in total of 1,825 quinariae -- 73,000 m3 (19,000,000 US gal) per 24 hours: 390-1 : 273 . The water was fed to twenty local reservoirs from which it was further distributed to various districts of Rome: 26 : 293 .
In 2016, what is likely to be a 32 m (105 ft) section of the Aqua Appia was excavated 17–18 m (56–59 ft) beneath Piazza Celimontana: 51 . Parts of the excavated section were relocated for reconstruction elsewhere.