De aquaeductu

With the recovery of Frontinus' manuscript from the library at Monte Cassino in 1425, effected by the tireless humanist Poggio Bracciolini, details of the construction and maintenance of the Roman aqueduct system became available once more, just as Renaissance Rome began to revive and require a dependable source of pure water.

One of the first jobs he undertook when appointed water commissioner was to prepare maps of the system so that he could assess their condition before undertaking their maintenance.

He was well aware of the seminal work De architectura by Vitruvius, which mentions aqueduct construction and maintenance of the channels, published in the previous century.

Waste water would end up primarily in the main sewers, which led into the Cloaca Maxima and finally the river Tiber.

Frontinus was very concerned by leaks in the system, especially those in the underground conduits, which were difficult to locate and mend, a problem still faced by water engineers today.

Silting of the channels was another common problem, especially those aqueducts that drew water directly from rivers, such as Anio Novus, and numerous settling tanks (each one being known as a castellum) were built along their lengths.