This case study shall take into account the integrations and transformations of ancient aqueducts with various needs at different ages.
The majority of ancient Roman aqueducts flow from the Apennines (east of Rome) where the springs are sited on limestone basis. Two of them (Alsietinus and Trajan Aqueducts) came from Sabatini mountains, a volcanic region located in the NW of Rome and they were routed adjacent to one another. The quality of this water was lower than others coming from limestone layers, but had great richness because it supplied the Naumachia, mills, irrigation systems. For this reason over the centuries, the two aqueducts have been subjected to destruction by invaders. They are an uncommon example of integrations, transformations and restorations related to the ages.
The Alsietinus Aqueduct, built in the year 2 BC by Emperor Augustus, supplied Rome with water caught from Lake Alsietinus (a small lake, today known as Lake Martignano, close to Bracciano), reaching the district of Trastevere. Its main purpose was to provide water to for the well known naumachias basin as well as for the irrigation system of Emperor Augustus’s gardens.
The Trajan Aqueduct: In the year 109 AD Emperor Trajan built a new aqueduct partially following the previous course of the Alsetinus Aqueduct. The course was from manthianus resort (NW of Bracciano Lake) to Rome by tracking the Bracciano Lake (Sabatinus Lake) board from NW to SE. The aqueduct collected spring water coming from the Sabatini mountains. The aim was to assure water supply to the city of Rome, as the previous Alsietinus Aqueduct was not sufficient anymore because the lower water level in the Lake brought about a scarce hydraulic discharge. The aqueduct was in use for centuries.
By 1605 the Pope Paulus V wished to increase the capacity of the Trajan Aqueduct to supply water to Janiculum Hill and the Vatican. This project provided a direct connection between Bracciano Lake and Trajan Aqueduct. The restoration of the aqueduct has been so important that the upper part of Trajan Aqueduct was practically abandoned and the brickwork was renamed to Pauline Aqueduct.
In the 1980s, the need of Rome for a wider drinking water supply requested a new duct from Bracciano Lake to the City. The duct, collecting water from Lake, adjoined the Pauline Aqueduct course including a sanitization plan of the Bracciano catchment area and has been stopped in Trionfale district were the water was passing through a sanitization plant.