LANDSCAPE MODIFICATION FOR WATER STORAGE: RESERVOIR CONSTRUCTION AND REUSE AT TALL DHIBAN, JORDAN

Evidence for large-scale water storage at Tall Dhiban, in central Jordan, has previously been attributed solely to Iron Age utilization of natural karstic bedrock depressions via the construction of plaster-lined walls, which enclosed a topographic low point on the Tall in order to produce a large open-air reservoir (Adelsberger et al., 2011). Further work at Dhiban has revealed a more complex history of reuse of this feature, with the original large plastered wall built at the beginning of the Iron IIB period (late 9^th century BCE) and later incorporated into a smaller, modified reservoir. This modification involved building a second wall along the inside of the original plastered Iron Age construction, and reducing the storage capacity of the natural depression of the reservoir by building a new perimeter wall perpendicular to the original Iron Age wall. Although dates of modified reservoir use have not been determined, a maximum age can be provided on the basis of a coin from the 18^th year of Antonius Pius (154/155 CE) found beneath the inner reservoir wall. Later, and presumably after large-scale water storage had ceased, reservoir walls were intentionally robbed down to a single course and covered over with fill containing Byzantine period ceramics. Agricultural terrace construction also took place upon this artificially flattened space, where preserved Red Mediterranean soils buried c. 25-30 cm below the present surface retain clear granular ped structure. This northern part of the karstic depression appears to be deeply buried by a massive slope failure, suggesting that the northern end of the storage feature, if not the entire reservoir, had already been rendered unusable by slope failure by the time of the Byzantine modifications. This more complex history of reservoir construction and, potentially, the end of large-scale water storage at Dhiban may provide insights into the relationship between Dhiban inhabitants and environmental conditions in this arid zone.