At the time when Rome conquered Carthage much of the city’s water was supplied either from wells or home cisterns that were fed by rainwater harvesting and were often at least two meters deep so could hold several thousand litres of water.
How would Roman settlers survive in conditions so different from Rome?
Would this region subsist the well known water displays, like fountains and baths?
Actually, the combining of the Roman technology (i.e. aqueducts) with the Punic techniques (i.e. cisterns) suceeded to bring the power of water to North Africa.
Never in ancient Tunisia, and on basis of archaeological documentation, a water policy has been so well designed and successfully implemented than during the Roman period. Roman emperors and local communities considered water a state affair, similarly to bread and the public games. They considered their responsibility to provide free acess to water for every citizen within their constituency without exception.
The remains of the cisterns in Malaga (la Malga) are located on the north-northwest side of Byrsa Hill. They comprise of a series of fifteen cisterns lined one after the other, forming, from the south side, a transverse compartment which had probably served as service compartment. The entire structure forms a rectangle shape of size 131m by 102m. Barrel-vaulted, each cistern was internally 100m long, 7.5m wide and 4 m of deep. Thus, their maximum capacity amounted to more than 44 000 m3, making them the greatest cisterns in Roman antiquity.
Converted for other uses, such as stable blocks, after the fall of Rome, the Malaga Cisterns have survived remarkably well and are today one of the more interesting Roman sites to explore.
The cisterns of Malaga are lined along the southern facade of a part of the aqueduct of Carthage that feeds them. However, the construction of the Malaga cisterns preceded that of the aqueduct for about a century, as the aqueduct was probably built in the middle of the 2nd century AD. Archaeological research has not yet been able to clarify the functional relationship between the two monuments.
Traveling 132 km through plains, hills and valleys, the Zaghouan aqueduct of Carthage erected in the 2nd century AD is the longest of Roman antiquity. This aqueduct was responsible for delivering most of the water to Carthage: its daily flow is estimated at 25 000 m3. That volume was sufficient for an average consumption of 250 liters per capita, based on an estimated population of 100,000 inhabitants. The aqueduct has two sources, the first is about fifty kilometers towards the direction of Zaghouan and the second is thirty miles southwest of Zaghouan to Djougar.
The aqueduct of Zaghouan, has always been an object of admiration, as it is a powerful testimony of a pioneer hydraulics technology. Its overground parts, more than 17 km long, with the height and rythm of its majestic arches, mark the refinement of materials and the beauty of its architecture. Its longevity has defeated time.
It has become customary to establish, without being possible to prove, a causal relationship between the construction of the aqueduct in Carthage and the construction of another water system no less grandiose, the Baths of Antonin, which according to an inscription was completed in 162 AD.
The aqueduct continued to function until at least the end of the Vandals (536 AD). It is believed that during the Byzantine period, which was marked by frequent political unrest and insecurity in the rural areas, the aqueduct began to deteriorate, without though going completely out of service.
More than six centuries later, Sultan Hafsid (also known as Abu Abdullah Mohammed al Mustansir I), gave new life to the aqueduct by making the necessary refurbishment from 1250 to 1267, to link it with the new construction, at the Kasbah of Tunis which run through the gardens of Ras-al-Tabia, of Bardo and Rabta.
The bridge and dam of El Battan: The bridge-dam of El Battan is another illustration of the past use of wadis in Medjerda plain, near Tunis. Built in the 16th century AD, the bridge has 16 arches, allowing the channeling of water to irrigate farmlands and to operate the water mills of the region.