ĀB-ANBĀR i. History

The term āb-anbār is common throughout Iran as a designation for roofed underground water cisterns. In Turkmenistan the term sardāba is found for similar structures (see, e.g., N. S. Grazhdankina, Stroitel’nye materialy sardob Turkmenistana, Izvestiya Akademii Nauk Turkmenistanskoi SSR, 1954, no. 4; G. Pugachenkova, Puti razvitiya arkhitektury yuzhnogo Turkmenistana pory rabovladeniya i feodalizma, Moscow, 1958, pp. 243, 394). Early Islamic sources in Arabic appear to use the words eṣṭaḵr for a covered tank or cistern (Le Strange, Lands, pp. 276, 285); and in 14th to 16th century texts, maṣnaʿ can be understood as designating a cistern (Jāmeʿ al-ḵayrāt, p. 28; Vaqfnāma, p. 875; Tārīḵ-e ǰadīd-e Yazd, p. 129).

The āb-anbār was one of the constructions developed in Iran as part of a water management system in areas reliant on permanent (springs, qanāts) or on seasonal (rain) water. A settlement’s capacity for storing water ensured its survival over the hot, dry season when even the permanent water supply would diminish. Private cisterns were filled from qanāts (man-made underground channels) during the winter months before the floods, while surplus flood water could often be stored in open tanks, as well as in the large, public, covered cisterns (Wulff, Crafts, p. 258; Pugachenkova, Puti, p. 243). Water was brought to the cisterns by special channels leading from the main qanāt or holding tanks and was controlled by sluice gates. The āb-anbār, a ventilated storage chamber, could then provide cool water throughout the summer months. Often rooms or pavilions were built within the complex of the cistern to provide a comfortable resting place as well.

While private houses may have had their own cisterns, filled in turn from the qanāts or streams, in desert towns like Yazd or Ṭabas the more noteworthy and elaborate structures were built for public use, often as part of a vaqf, within towns as well as on caravan routs (see e.g., A. U. Pope and E. Beaudouin, “City Plans,” in Survey of Persian Art, pp. 1391-1410). Two types of structures have been noted, a cylindrical reservoir with a dome and a rectangular one supported by piers or pillars (see M. Siroux, Caravansérails d’Iran et petites constructions routiers, MIFAO, Cairo, 1949). Each was marked by a portal, often with an inscription giving the name of the benefactor (builder or repairer) and the date (see, e.g., examples in H. Narāqī, Āṯār-e tārīḵī-e šahrestānhā-ye Kāšān o Nāṭanz, Tehran, 1347 Š./1968). The portal opened into a steep, barrel-vaulted passageway, leading down to the reservoir.

Although a detailed study of all variations of construction techniques of the āb-anbār in Iran still remains to be done, Grazhdankina’s analyses of similar structures in Turkmenistan, as well as observations by Beazley, Wulff, Siroux, and Sotūda (see below), allow a general outline of the technique. The prime objective in constructing an āb-anbār is to provide a totally waterproof container for a large volume of water while allowing for proper ventilation and access. The excavation was lined with overfired brick set into a sand and clay mixture. It was then covered with a layer (about 3 cm) of waterproof mortar, sārūǰ (see Grazhdankina, Materialy, for specific analyses of the mortar). Larger cisterns were often lined with an additional double layer of bricks, covered with another layer of sārūǰ of slightly different composition, and finished with a hard plaster coat.

The early history of covered cisterns in Iran has not been studied, although it is possible that a major elaboration of construction techniques may have taken place during the Parthiann and Sasanian periods, when water management constructions (dams, weirs, qanāts) were built extensively. The geographers of the 10th century apparently described a fully functioning system of cisterns. The Ardestān desert road, as well as the road from Isfahan to Nāʾīn, was lined with open tanks and domed cisterns. In fact, these domes often served as the only sure markers on desert routes. ʿAżod-al-dawla (A. D. 943-89) built an enormous vaulted cistern at Eṣṭarḵr.

Investigations in the ceramicists’ qaurter of 11th-12th century Marv have revealed a cistern located in close proximity to the mausoleum of Moḥammad b. Zayd. Its cylindrical reservoir had a 6.1 m diameter, and was apparently ventilated by a pair of window-like openings. Its covering has not survived or may not have existed. The cistern next to the rebāṭ al-Taḥmalaǰ, datable by its brick size to the same period and covered by a dome (17 m in diameter and 8 m deep), had a capacity of 150,000 liters (Pugachenkova, Puti, pp. 244, 394). Similar structures have been found recorded by Masson on the major desert routes of Central Asia and Turkmenistan, though most extant examples are of a considerably later date. The cistern associated with the 861/1456 mosque at Anaw is 6,5 m in diameter and was fed by three channels (Figure 8).

Figure 8. Cistern at Anaw Associated with the Mosque Dated to 861/1456 (after Pugachenkova)View full image in a new tab

Regional surveys of the Yazd and Kāšān regions have listed scores of āb-anbārs, located either within settled areas or along caravan routes. While there are one or two earlier ones, most are dated or datable to the 18th and 19th centuries (see Narāqī, Āṯār-e tārīḵī; Tārīḵ-e ǰadīd-e Yazd; Jāmeʿ-e Mofīdī in bibliog.). The earliest dated āb-anbār is in Yazd, behind the masǰed-e ǰāmeʿ, and is dated 878/1473 (Ī. Afšār, Yādgārhā-ye Yazd I, Tehran, 1348 Š./1969, fig. 166).

Āb-anbārs of the Safavid and later periods were built with two or more ventilating towers (bādgīrs). The āb-anbār of the moṣallā at Nāʾīn, most likely a nineteenth century building, illustrates the typical use of the towers for the ventilation, as well as the relationship of the cool room pavilion to the āb-anbār (Figure 9). The āb-anbār of Ḥāǰǰī Sayyed Ḥosayn Sabbāḡ in Kāšān dated by its inscription 1240/1824 is a more elaborate example of a rectangular hypostyle type. Built within the main bazaar, it has a large portal decorated with moqarnas and glazed brick and tile inlay. A set of pavilions or rooms built above the reservoir and cooled by it has a separate access from a series of workshops (Narāqī, Āṯār-e tārīḵī, pp. 306-308; Siroux, Anciennes voies et monuments, p. 125). The use of bādgīrs was particularly well developed in Yazd, where there are several āb-anbārs with four bādgīrs as well as the famous āb-anbāršaš-bādgīrs with six.

Figure 9. Cistern of the Moṣallā at Nāʾīn (ca. 13th/19th century; after Seyhoun)View full image in a new tab

AB-ANBĀR ii. Construction

Cisterns are built in towns and villages throughout Iran, as well as at crossroads, caravanseries, and hospices (rebāṭ). While town cisterns may be filled with rain water or from qanāts, most āb-anbārs along caravan routes are filled from the spring torrents of nearby streams; during the dry season gradient weirs are constructed in the stream bed in order to divert water to the cisterns when the winter snows melt and the streams rise. Use of two or more cisterns becomes necessary when the volume of water is large. As one cistern becomes full, the water collecting behind the weir can be directed into a second cistern by diverting it into a second channel dug alongside the first, as this channel is opened and the other closed off. Should this channeling system fail to draw off a sizable enough volume, the water would built up behind the weir and eventually destroy it.

Mode of construction. Cisterns built inside private dwellings are usually square or rectangular; public cisterns in towns or along the caravan routes are generally round. While the former have a flat roof and are often built into the foundation of the house, the latter have a distinctive hemispherical or almost conical roofing.

Water remains quite cool inside the cistern, since it is generally built beneath ground level and is insulated by very thick walls. In most parts of Iran, but particularly in the south, one or more ventilation towers (bādgīr) is built along the edge of the cistern’s roof, directly on the tank wall and connected by a duct to the upper part of the cistern chamber under the domed roof. Fresh air entering through these ducts keeps the air inside the cistern chamber circulating and the water cooled. The six-ventilator cistern to be found in the city of Yazd is probably the most elaborate example of the type equipped with ventilation chambers. In the case of cisterns with domed or conical roofs, the center of the roof is sometimes pierced, and a short ventilation chamber made of brick is built directly over the cistern chamber. A duct inside the ventilation chamber leads from the openings or slats (that catch the breeze on top) directly inside the roof, again circulating air inside the cistern chamber. The height of these ventilation chambers is generally about one meter, though some can occasionally be seen that reach a height of two or even three meters.

Construction. Materials used consist essentially of stone or baked brick with lime-mortar and plaster. After the pit that will house the cistern has been hollowed out, the bottom is covered with slaked lime-mortar. When this floor hardens, the builder erects the tank’s walls, made of baked brick or stone. The bricks are generally plunged in water before being laid. The filling between bricks or stones consists of lime-mortar. After the roofing of brick and slaked lime is laid, the tank’s floor and walls are finished with a coating of plaster.

A type of cistern called rīḵtaʾī (“poured,” i.e. made of poured lime-plaster) is considerably cheaper to build. First the perimeter of the tank’s walls is marked out, and the earth within the wall area is dug out to the desired depth. Next lime-mortar is poured into the square or rectangular trench until it is filled nearly to the ground level. This is left for a week or two until the mortar settles and is solidified. Then the area of earth bounded by the mortar walls is dug out down to the desired floor level. The floor is built by pouring lime-mortar; and, finally, when the walls and floor are dry, they receive a coat of plaster.

Plaster is an indispensable material in the construction of the Iranian cistern, since the essential function, containment of water, is achieved by the watertightness of the plaster. The type of plaster most commonly used, called sārūǰ, is a compound from six parts clay, four parts lime, one part ash, and an amount of lūʾī sufficient to keep the compound from cracking; this last consisting of the seeds and pods of an extremely soft and pliable species of reed. The first step in the preparation of this plaster is the mixture of the clay and lime, to which water is added. All of this is made into a relatively hard, clayey substance which is worked for one or two days. Next the ashes and lūʾī are pounded into this mixture until the various components have been thoroughly blended. This pounding is done with wooden sticks about 10 cm in diameter and one meter long, one end of which has been tapered to serve as a handle. This last step is important, because the more the mixture is pounded and kneaded, the more durable it is. When the plaster compound is ready, it is spread on the walls and the floor of the cistern with a trowel. The next step is to score the plaster surface with a lentil-shaped stone that fits in the palm of the hand and is called a mohra (“bead”). This scoring goes on for several days until the walls and the floor of the tank begin to perspire, a sign that the components in the plaster are holding together fast. Only then is the cistern filled with water.

Drawing water. Cisterns may be provided with a tap. When the place for the tap is reached in the course of construction, an additional pipe for it is built into the wall; and a plaster compound (half clay and half lime) called “bastard clay” (gel-e eḥarāmzāda) is pounded with the feet into the space above the pipe. Water is taken from this type of cistern by means of a separate chamber, containing a staircase, about as deep as the adjoining tank chamber. The stairs are wide enough so that persons going up and down with buckets, gourds, or leather bottles will not get in each other’s way. Two, three, or even more taps are sometimes installed. A few cisterns have been observed to have two separate stairs on opposite sides. In the case of the cisterns built alongside roadways, however, the normal procedure is to construct the staircase within the cistern chamber itself, so that the water is drawn directly from the tank.

Capacity. The capacity of the traditional cylindrical cistern varies generally from 300 to 3,000 cu m. This upper limit is dictated by the fact that the maximum diameter allowed by the method of construction is about 20 m. If the depth of the tank is up to 10 m, its capacity would be about 3,000 cu m. In a few localities the cisterns have an even greater capacity, and some exceptional examples have been cited as able to hold up to 100,000 cu m. These are not round tanks, however, but square or rectangular cisterns with columns placed in the middle of the tank chamber in one or two rows. These support a roof consisting of a series of domes or barrel-vaults.