Construction of numerous engineering structures for water supply in all part of the empire secured place for roman engineers in world history of architecture. Large-scale construction of hydroelectric installations, along with roads and bridges began during the reign of Augustus. The strength of the buildings allows using some of them nowdays.
Roman aqueducts were an impressive network, the remains of which can be found in many European countries, once belonged to the empire.
Aqueduct Gaidary (photo made by Professor M. Dering during the expedition)
There were 11 aqueducts in the city of Rome itself.
Roman aqueducts often contained underground tunnels, sometimes significantly long. For example, underground part of Martius Aqueduct, constructed in 144 AD is 80 km., remarkably it is still in operation.
But it is not the longest one in Roman Empire, prof. M. Doring from Darmstadt discovered in 2004 an aqueduct with a length of 170 km, underground part surpassing all the others. In some places the depth of the tunnel reaches 80 m, total length of the tunnels that were meant to supply cities of Decapolis with water, rich city of Syria province (now the territory belong to Jordan), Gadara, included, - 106 km (there are three of them - 1, 11 and 94 km long respectfully).
The population of Gadara was about 50,000 people, Romans, having in possession of technical and financial resources, constructed a complex aqueduct, with an aim to turn the deserted land into prospering oasis.
Construction took about 100-120 years. It is assumed that Legionnaires force was used for construction as it was a common practice with road construction. More than 600,000 sq.m. of rock was excavated.
The scheme works aqueduct Gadara, published in the journal "Der Spiegel"
Modern specialists were impressed with a slightest flaws, the construction carried out with precise accurance, - 30 sm deviation for 1 km of the first 60. Tunnel is 2.5 m high and 1.5 m wide.
Construction would have consumed too much time if the works had been carried out sequential. Prof. Doring’s expedition proved the construction became possible thanks to the tracing the route of the tunnel on the surface and excavating service tunnels each 20-200 m for further simultaneous excavation of many parts of the tunnel.
Map of the Roman aqueducts, made within the framework of Atlas Project of Roman Aqueducts
The complexity of works and the scale prove that the technologies of underground constructions were well-known in ancient Rome, and Roman engineers used them for increasing livability and comfort of their cities.