Almost all precipitation in (semi-)arid regions is lost through evaporation, surface runoff and seepage, and becomes unavailable for agriculture. Ancient societies dealt with similar problems. In ancient times land-use systems and resource management, particularly elaborated water-harvesting schemes, were employed to prevent this loss. 

In the Udhruh region, 12 km to the east of Petra, a variety of such techniques was practised turning the steppe into green oases. After years (2011-2015) of exploratory archaeological field work we – a joint venture Dutch and Jordanian academic and expertise team – can conclude that the area around Udhruḥ is one of the most complete and best preserved field ‘laboratories’ to study the long-term development of innovative water management and agricultural systems throughout the Nabataean, Roman, Byzantine and early Islamic periods in southern Jordan. 

Aims 

Our research program will focus on the diachronic reconstruction of the antique agro-hydrological techniques which were employed to cultivate this arid landscape and the societal conditions that contextualised them. An international and interdisciplinary research team will examine, in close cooperation with the local communities, what the key to this water management and agricultural success was in ancient times. We also try to find means how this knowledge can be used for revamping these ancient water systems for current agricultural use. 

Archaeological research of ancient water harvesting and agricultural schemes

Three ancient agro-hydrological systems can be distinguished in the Udhruḥ region. Systems that extract water from different sources and for different purposes, whereby agricultural use seems to be the prevailing aim. 
These are:
I.    A perennial source in Udhruḥ was used to irrigate a patchwork of compound gardens. 
II.    In the hilly area northwest of Udhruḥ a combination of ancient rainwater-catchment and run-off water harvesting techniques is observed. These water harvesting schemes were employed to hold and direct run-off water that would otherwise get lost. 
III.    An impressive network of well-preserved ancient subterranean and surface-water conservation measures and connected irrigated fields – a qanat-system - was recorded in a large flood plain largely covered by alluvial deposits southeast of Udhruḥ (Wādī al-Fiqai). The Udhruḥ qanat (figure 2-3) made use of the extraction of deep percolation water, whereby also solutions were applied to prevent loss through evaporation. 
 

Approach

The last system – the Udhruḥ qanat – will be our research focus for the coming years (2019-2023), because of the ingenuity and investments made on its construction and reworking, its long durée usage throughout several classical and Islamic periods, and its completeness in preservation. Through a combination of contextual small-scale excavations and non-destructive ground-based methods (ground-penetrating radar, magnetometry, (aerial)photogrammetry, 3D-scanning) obtainable data will be retrieved on the position, dimensions and interconnections of these and other structures in this geologically diverse archaeological landscape. The comparative OSL and 14C dating will provide a solid chronological framework for inter alia the construction, maintenance and disuse of the Udhruḥ qanat-system and to the study of antique qanat-systems in general. 

Trying to unravel the exact modus operandi of this qanat scheme and the continuity in use will be a great challenge for our research project in the coming years. Only by practicing an interdisciplinary approach can this be accomplished whereby archaeological research is integrated with historical, geophysical, water resources, bio-scientific and biogeochemical soil studies.
 

Societal relevance

On the one hand we think that this approach will help us to comprehend the agro-hydrological landscape from a diachronic perspective for the Udhruḥ region. On the other hand we hope that this will also lead to translational and innovative thinking which can contribute to possible sustainable agricultural and water management solutions for future use in these regions. 

*This project is sponsored by the Max van Berchem Foundation, established in 1973 in memory of Max van Berchem (1863-1921), the founder of Arabic epigraphy. Based in Geneva, the aim of the Foundation is to promote the study of Islamic and Arabic archaeology, history, geography, art, epigraphy, religion and literature. 

Driessen M.J., F. Abudanah, 2018. The Udhruh region: A green desert in the hinterland of ancient Petra. In: Zhuang Y., M. Altaweel (eds.) Water Societies and Technologies from the Past and Present. London: UCL Press. 127-156. 

Velasco-Sanchez A., Driessen M.J., Abudanah F., Nobels P.R., Comans R.N.J. & Hoosbeek M.R. (2022), Soil chemical changes in ancient irrigated fields of Udhruḥ, southern Jordan, Geoarchaeology 37-2, pp. 374 - 384.