30 19 43.0 N
35 26 31.0 E
Even though Petra was built in a hostile and barren desert, it was able to support from 30,000 to 40,000 inhabitants because of the water supply, drainage, and flood control infrastructure developed by the Nabateans.
The ancient Nabatean water supply control system in Petra is a masterful period example of advanced hydraulic and flood control engineering. This system includes water supply canals, an aqueduct, a tunnel, reservoirs, cisterns, piping, and flood control dams that proved to be efficient and sustainable, serving a prospering urban community of more than 30,000 people.
Located in southern Jordan, Petra is approximately 160 miles south of Amman. Though it was previously inhabited, Petra didn't flourish until after the arrival of Nabateans who were originally Arabian nomadic people. At Petra they developed a civilization based on the caravan trade up and through the Arabian Peninsula sometime before the fourth century B.C. until faster and cheaper sea routes became available. Petra was absorbed into the Roman Empire in A.D. 106. The city was occupied up through the fifth century A.D.
Even though Petra was built amidst a hostile and barren desert, it was able to support from 30,000 to 40,000 inhabitants because of the water supply and drainage and flood control infrastructure developed by the Nabateans. They managed to build a diversion dam and long tunnel to protect downtown Petra from ravaging floods from the Wadi Mousa Basin. To maintain a water supply in the desert, they cut into solid rock to build canals coupled with piping; built reservoirs and cisterns to maintain sustainability; and included particle-settling basins that served to purify the water.
Being located at the center of major trade routes, the Nabateans had the distinct advantage of being able to adopt Greek and Roman hydraulic technology. However, while the Nabatean engineers incorporated of these foreign ideas into their own systems, their methods were unique because of their application of water conservation techniques.
The Nabateans of Petra have left much for modern engineers to admire and learn about system reliability and longevity. In a desert region where annual precipitation is only 6 inches per year, they learned how to utilize channels, cisterns, flow pipeline and reservoirs to supply a major population center with a constant water supply throughout the year.