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Wells, cisterns and aqueducts in the ancient world (Jeremiah 38)

Illustration: Aqueduct in Rome

The semiarid climate of the Mediterranean basin made water acquisition ans storage a critical issue

Wells

A well is a deep reservoir fed by percolation from the soil, by a spring or by groundwater. The lower part is usually dug into impermeable rock or built with rock and then coated with a thick layer of lime plaster, which prevents seepage. It is possible either to tap into a natural spring or to dig down to the groundwater level. Archaeologists date the first such use of plaster around 1200 B.C.

A very ancient well in Jerusalem, known as “Jacob’s well”, is nearly 40 m deep. Water was taken from it by lowering a drawing vessel attached to a rope. The high concentration of pottery sherds found in Near Eastern wells suggests that clay pots were used for this purpose, although wooden pails found in the Athenian agora (marketplace) seem to have served the same function. Wells were often dug in rural areas in order to provide water for flocks and herds (Genesis 26:18, 2 Chronicles 26:9-10). A stone slab or wooden planks covered the mouth of the well when it was not in use to prevent people or animals from falling in and to lower the risk of pollution from the surface debris (see Genesis 29:10, Exodus 21:33-34).

Cisterns

A cistern is a collection chamber that gathers runoff. Cisterns typically have a bottle or bell shape, with a narrow top to prevent evaporation. The entire interior is coated with plaster, so that every drop of water is preserved. Water was drawn from a cistern in the same fashion as from a well. Homes could hac\ve private cisterns (see 2 Kings 18:31, Proverbs 5:15); in fact, excavations at Tell en-Nasbeh, a site north of Jerusalem that is usually identified as the Biblical Mizpah, revealed 50 cisterns from the ninth century B.C. Cities had larger, public cisterns. In the temple area of Jerusalem, for example, excavators discovered 37 large cisterns, the largest of which is known as the “Great Sea”. About 13 m deep, it can hold over 10,000 cubic m of water! Also in Jerusalem is the Pool of Siloam, constructed by Hezekiah (2 Chronicles 32:30) and embellished by Herod – the Upper Pool of Isaiah 7:3. In order to ensure a steady and reliable supply of water to this reservoir, Hezekiah undertook the construction of a tunnel aqueduct that travels over 500 m through solid rock from the spring to the cistern. Dry cisterns also served as detention cells (Genesis 37:22-24, Jeremiah 38:6).

Aqueducts

The first aqueducts (artificial water channels similar to pipelines) were simple channels dug into the ground. Eventually, the channels were formed by plastering fieldstones together and covering the aqueduct with stone slabs to prevent contamination. Shallow settling basins were dug intermittently, allowing the heavier sediment to drop out of the water. Pools and reservoirs were often placed along the aqueduct to control water flow. The earliest known substantial aqueduct – from the early eighth century B.C. – is at Uratru in Turkey. The Assyrian king Sennacherib constructed a 55 km aqueduct to Nineveh. Excavators have found numerous inscriptions along the course of the conduit praising Sennacherib for this impressive deed.

The masters of aqueduct construction, however, were the Romans. To this day the landscape of numerous Mediterranean countries is dotted with the remains of these engineering masterpieces. Ancient Rome was serviced by 11 aqueducts, the largest of which were the Marcia and the Anio Novus. Altogether the 11 aqueducts provided the capital with the largest volume carried to any ancient city.

The Romans are also famous for their ability to carry water across challenging terrain. Valleys were traversed in one of two ways. If the distance from the proposed water line to the valley floor was less than about 50 m, an arched bridge was constructed, containing a channel running along the top. The aqueduct was built so that the water ran dwonhill on a gentle slope. The tallest aqueduct of this type is the Point du Grad in southern France. Ir rises 49 m above the valley and supplied water to Nimes beginning in 19 B.C. Pergamum was the first major city in Asia Minor (western Turkey) to establish an alliance with Rome to construct Roman style aqueducts. Providing water to the upper city was a constant challenge, but engineers resolved the problem with a complex siphoning system.