Aqua Anio Novus

Aqua Anio Novus (Latin for "New Anio aqueduct") was an ancient Roman aqueduct supplying the city of Rome. Like the Aqua Claudia, it was begun by emperor Caligula in 38 AD and completed in 52 AD by Claudius:11:271:§21, who dedicated them both on August 1:11. The aqueduct—together with the Aqua Anio Vetus, Aqua Marcia and Aqua Claudia—is regarded as one of the four great aqueducts of Rome.

The quality of water Aqua Anio Novus delivered to the city of Rome left much to be desired:12, and before Frontinus' reforms of the water supply system its waters were used to supplement the flow of other aqueducts when needed:12—rendering waters in those too torpid in the process.