Detail of the Aqua Claudia and Anio Novus in the Park of the Aqueducts in Rome, June 2012

Aqua Claudia was an aqueduct of ancient Rome that, like the Anio Novus, was begun by Emperor Caligula in 38 AD. and finished by Emperor Claudius in 52 AD. Its main springs, the Caeruleus and Curtius, were situated 300 paces to the left of the thirty-eighth milestone of the Via Sublacensis. After being in use for ten years, the supply failed, and was interrupted for nine years, until Emperor Vespasian restored it in 71, and ten years later Titus once more.

The channel length was 45–46 miles (ca. 69 km, most of which was underground), and volume at the springs was 191,190 cubic metres in 24 hours. Following Nero's completion of the Arcus Neroniani, one of the aqueduct's branches, the Aqua Claudia could provide all 14 Roman districts with water. Directly after its filtering tank, near the seventh mile of the Via Latina, it finally emerged onto arches, which increase in height as the ground falls towards the city. It is also one of the two ancient aqueducts that flowed through the Porta Maggiore, the other being the Anio Novus. It is described in some detail by Frontinus in his work published in the later first century, De aquaeductu.

Text from: en.wikipedia.org/wiki/Aqua_Claudia

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Anio Novus is an aqueduct of Rome. Together with the Aqua Claudia, it was begun by emperor Caligula in 38 AD and completed in 52 AD by Claudius, who dedicated them both on August 1.

It was the highest in level of all the aqueducts that came into ancient Rome. After the water was apt to be turbid, Trajan made use of the two uppermost of the three lakes formed by Nero for the adornment of his villa at Subiaco thus lengthening the aqueduct to 58 miles and 700 paces. The lakes were created by dams in the river, and were the tallest of any built by the Romans. They were swept away by the river in the Medieval period. Its volume at the intake was 196,627 cubic metres in 24 hours. From its filtering tank near the seventh milestone of the Via Latina it was carried on the lofty arches of the Aqua Claudia, in a channel immediately superposed on the latter.

Before the reforms, the aqueduct was freely used to supply the deficiencies of other aqueducts, and, being turbid, rendered them impure. It is described in some detail by Frontinus in his work published in the later first century, De aquaeductu.

Text from: en.wikipedia.org/wiki/Anio_Novus