In antiquity, aqueducts transported spring water or running water to communities, principally to cities, but also to palaces, fortresses, monasteries, and farms. These water systems supplied fresh water for individual everyday use, for pools in private residences, and for public use in bathhouses, fountains, and reservoirs. They transported water from a high place to a low place according to the law of gravity. Aqueducts begin at springs, a few of which were enhanced by built structures: at Jerusalem, Caesarea, Emmaus, Sebaste, Beth-Guvrin, and ῾Ein-Boqeq in Palestine. At first, channels for the moving water were dug into the ground, but eventually they were hewn or built of field stone, sealed with waterproof plaster, and covered with flat stone slabs that prevented the water from becoming polluted. In a number of places, pits were dug, into which residue from the sediments in the water could settle. The channels in which the water flowed were generally cut in a rectangular shape; some narrowed at the bottom, to become trapezoidal. The dimensions of the channels were determined by the amount of water they were designed to carry: from 1.4 × 1.8 m long (the lower aqueduct at Caesarea) to 0.1 × 0.14 m long (the lower aqueduct at Emmaus) and generally about 0.3–0.5 m wide and 0.5–0.8 m deep. The aqueducts themselves were usually built from small stones that did not exceed 0.2 m in length; the stones were held together with mortar. In order to cross valleys and mountain chains, arched bridges were built and tunnels were dug. Tunnels first appeared in the Iron Age in Jerusalem in Palestine and at Erbil in Syria. Many were dug in the Hellenistic, Roman, and Byzantine periods, several of which had shafts 33–56 m apart. Such a system allowed the digging to be carried out simultaneously in all the shafts, so that work on the tunnel could proceed more quickly. Tunnels constructed in this manner were used at Akko, Beth-ha- ῾Emek, Gaaton, Jerusalem, Caesarea, and Sepphoris. Shorter tunnels without shafts were found at Susita, Sebaste, Jerusalem, Jericho, Qumran, and Hyrkania.

From the Hellenistic period onward, it was customary in deep valleys to use an inverted siphon to move water. This consisted of a lead or clay pipe that could be closed off. This important invention conveyed water to cities on high hills (at Pergamon the ridge was about 200 m high). To regulate the flow of water, pools and reservoirs were built along the path of the aqueducts. Near the city or inside it, the water entered a large reservoir (Sepphoris, Susita) or an enclosed pool (Sepphoris, Tiberias, Jericho, Petra, Humeima) or entered into large water pits (Masada, Cypros, Sartaba, Hyrkania).

In the Roman period, an inverted siphon built of stone links was in use at Jerusalem, Susita, and Beth-Yerah. Linked stones were used in building the arched bridges that appear for the first time in the first century BCE. These bridges are considered the most impressive structures associated with the aqueducts; together with the inverted siphon (sometimes also in combination, as at Aspendos in Anatolia) and the tunnels, they mark the high point in the development of aqueducts.

The earliest aqueduct is Menua's canal dug at Urartu in Turkey, at the beginning of the eighth century BCE. It conveyed spring water for a distance of about 56 km (about 35 mi) to the foot of the settlement at the citadel of Urartu. Knowledge of this technology traveled from Urartu to Assyria, where, at the end of the eighth century BCE, Sennacherib built two aqueducts for the cities of Nineveh and Erbil. The aqueduct at Nineveh was about 55 km long and included a number of tunnels and bridges. Inscriptions glorifying Sennacherib have been discovered on the largest of the bridges (approximately 300 m long and about 12 m wide). A shaft tunnel was dug for the aqueduct at Erbil. Hezekiah's Tunnel (533 m long) was built in Jerusalem in the same period. It passed under the city, to the other side of the ridge, going east to southwest, in order to bring water into the city. The technique of conveying water by means of aqueducts also reached classical Greece, where, in the sixth century BCE, Eupalinos constructed a tunnel 1,040 m long to bring water to the city of Samos. Hezekiah's Tunnel and the tunnel of Eupalinos, both of which were built without trenches, are considered the greatest works of water-engineering technology in the preclassical period. The techniques developed by the Greeks for building aqueducts arose from the need to hide their water systems from their enemies. As a result, they constructed underground tunnels. Just such a water system in Palestine brought water from a distance of about 14 km (8.75 mi.) to the city of Ptolemais/Akko, at the beginning of the third century BCE; it is the first aqueduct to bring water from such a distance.

In the second century BCE, in the desert of Palestine, aqueducts gathered floodwaters into gigantic water pits located in palaces and fortresses. These aqueducts are distinguished by a deeply cut channel. At Sartaba and Hyrkania, an inverted siphon was built that allowed water to be conveyed to the pits situated along the slope of the fortress, according to the principle that water in a pipe will always rise to its original height. An aqueduct was built from the springs at Wadi Qelt to the palaces of the Hasmoneans in Jericho; in it a clay pipe was installed that was used as an inverted siphon to raise water to the fortress. The lower aqueduct to Jerusalem is dated to this same period.

In the Roman period, aqueducts were built in most of the cities of the ancient Near East. The most important ones were in Palestine, at Caesarea and in Jerusalem. The upper aqueduct at Caesarea, first built either by Herod the Great or by his followers, rests on impressive arches to keep water at the desirable height. Thus, the water could reach every part of the city by force of gravitation. At the time of the emperor Hadrian, a second aqueduct was affixed to it that bears no fewer than nine imperial inscriptions glorifying the emperor for building the structure. Jerusalem's aqueduct in this period is an arrangement of four aqueducts whose total length is about 80 km (about 50 mi.). Additional aqueducts were built at Antioch, Tyre, Tadmor/Palmyra, Banias, Susita (three aqueducts), Gadara/Umm Qeis, Tiberias (two), Sepphoris (two), Beth-Shean (three), Abila (three), Dor (two), Legio, Sha῾ar ha-῾Amaqim (two), Sebaste/Samaria (two), Shechem, Emmaus (two), Beth-Guvrin (two), Humeima, and Petra (two), among others. An inverted siphon built of stone links is found on the ridge (about 45 m deep) at Susita and in the valley of Bethlehem, on the high (about 40 m deep) aqueduct to Jerusalem. The aqueduct at Tiberias has a secondary water line (about 20 m deep) that leads to the bathhouse at Beth-Yerah. Stone inverted siphons such as these are widespread in many Roman cities in western Anatolia.

Bridges support aqueducts in only a few places: at Cypros and Hyrkania and in Wadi Qelt, Samaria, Tiberias, Jerusalem, and Na῾aran, near Jericho. There probably was a bridge at Sepphoris, but it has been completely destroyed. In other places, high support walls were built to guard the aqueduct as it passed through low-lying regions: at Cypros, Hyrkania, and Sepphoris. Aqueducts were used late into the Byzantine period. In the Early Arab period, an aqueduct was built at Ramla, then the capital of Palestine.

Jerusalem's aqueducts continued to operate in the Mamluk and Ottoman periods. In the Ottoman period, two aqueducts were built at Akko; the later one dates to the reign of the Pasha Süleyman and operated from 1814 to 1948. The Biar aqueduct, one of the four aqueducts to Jerusalem, was repaired by the British and still operates, as do the ones in Wadi Qelt and Wadi Auja, which were built in the twentieth century on the foundations of aqueducts from the Hasmonean period.

[See also Baths; Cisterns; Dams; Hydrology; Pools; Reservoirs; Sewers; and Water Tunnels. In addition, many of the sites mentioned are the subject of independent entries.]

Bibliography

  • ῾Amit, David, Yizhar Hirschfeld, and Joseph Patrich, eds. The Aqueducts of Ancient Palestine (in Hebrew). Jerusalem, 1989.
  • Olami, Yaacov, and Yehudah Peleg. “The Water Supply System of Caesarea Maritima.” Israel Exploration Journal 27.2–3 (1977): 127–137, pls. 16–17.
  • Stenton, E. C., and J. J. Coulton. “Oinoanda: The Water Supply and Aqueduct.” Anatolian Studies 36 (1986): 15–59.
  • Tsuk, Tsvika. “The Aqueducts to Sepphoris.” M.A. thesis, Tel Aviv University, 1985. In Hebrew, with English summary.
  • Tsuk, Tsvika. “The Aqueduct to Legio and the Location of the Camp of the VIth Roman Legion.” Tel Aviv 15–16 (1988–1989): 92–97, pls. 13–14.
  • Vitruvius, Pollio. De Architectura. Book 8. Cambridge, 1934.

Tsvika Tsuk

Translated from Hebrew by Eric S. Cohen