Don is an Adjunct Lecturer in the Discipline of Classics and Ancient History in the School of Humanities, specialising in the analysis of ancient water management systems, settlement history, and palaeolandscapes in the Near East with a particular focus on the application of aerial archaeology.

Following a lengthy geological career in the industrial sector, Don undertook doctoral research into all aspects of the water management history of the Greco-Roman Decapolis city of Gerasa (modern Jarash) in northern Jordan and was awarded his PhD by the University of Western Australia in 2019.

Don’s interdisciplinary approach to his research includes studies of the geoarchaeological, geomorphological and archaeometric contexts through fieldwork and careful analysis of published and unpublished sources. He specialises in the archaeological interpretation of remote sensing datasets (satellite imagery & aerial photographs) and historical photographs in the Near East.

Don currently directs the Jarash Water Project, an ongoing comprehensive multiperiod investigation into all aspects of historical water management in the Jarash district in northern Jordan. He has previously held research positions in aerial archaeological programs in Saudi Arabia (AAKSAU & AAKSAK) and has been involved in the Aerial Archaeology of Jordan (AAJ) project since 2008. He has published extensively on the archaeology of the Jarash district, including a monograph on water management up to AD 750 and separate studies of watermills, the monumental nymphaeum, landscape history, settlement history, the archaeological contributions of 19^th-century travellers, and Christian churches in Jarash.

Funding overview

Don Boyer. ‘Jarash Water Project, 2015 Field Season’. Rodney R. T. Prider Scholarship.

Don Boyer. ‘Jarash Water Project, 2016 Field Season’. Rodney R. T. Prider Scholarship.

Don Boyer. Jarash Water Project. ‘Dating of spring sources and related water supply installations to the Roman city of Gerasa (Jarash), Jordan to constrain the chronology of the network's construction and use. (Project N10082). Grant from the Centre for Accelerator Science at ANSTO through the Australian National Collaborative Research Infrastructure Strategy (NCRIS).

Research - Jarash Water Project

Overview

Gerasa (modern Jarash) in northern Jordan was one of the cities of the Decapolis. It grew from humble beginnings in the 2nd century BC to become a prosperous city in the Roman-Byzantine and Early Islamic periods (1^st to 10^th centuries AD). Major phases of public building took place in the early Roman period. They included temples, theatres, baths, a hippodrome and water monuments that today form the ruins of one of the best-preserved cities in the Roman Empire.

The Jarash Water Project (JWP) was established in 2012 as a doctoral study to investigate all aspects of the water management system to the city and its immediate hinterland. The interdisciplinary, contextual approach combines the evaluation of evidence from new ground surveys and a critical examination of evidence in the published corpus and unpublished archives with new interdisciplinary studies that provide geoarchaeological, palaeoclimatic and historical contexts. The doctoral research focused on the period before AD 750 and the results have been published in a monograph by Brepols (Boyer 2022) . The water management system’s source, transport and distribution components are systematically described, some in detail and many for the first time. The comprehensive study of natural springs highlights the concentration of strong springs in the Jarash Valley and the impact this had on settlement patterns and the distribution of irrigation networks. Aqueduct-fed storages (reservoirs and basins) are complemented by runoff storages (cisterns) in both rural and urban contexts, but wells (intersecting the water table) are rare. The city is naturally divided into two parts by the Wadi Jarash. Water on the eastern side city was sourced mainly from strong local springs, whereas the western side relied on extramural networks of open channel aqueducts supplied from karstic springs within 3.5 km of the city. Two groups of aqueducts—the north-west network and the northern network—brought water to the city’s western side, but the evidence points to the fountains and most baths being supplied from the north-west network only. The contribution of the northern network to central city consumers is unknown, and this network may only have supplied irrigation water until the Byzantine period, thus contradicting the widely held belief that Birketein, 1.5 km to the north, was the city’s primary water source. Radiocarbon dating shows that the earliest aqueduct to the city was used in the first century AD. The combination of terrain and proximity of the springs resulted in steep aqueduct gradients.

The complex urban distribution network relied on gravity. The fragmentary evidence suggests that open channel conduits delivered water to various castella divisoria, although few are preserved. Baths and fountains were key users: There is no evidence of private connections to aqueducts, and industrial use is mainly unquantifiable. Comprehensive spring-fed aqueduct networks irrigated large parts of the Jarash and lower Tannur valleys. The Roman water management system underpinned the growth of the city and the development of its rural hinterland. It continued to operate into the Early Islamic period but had to adapt to hydroclimatic change.

In the context of the Decapolis, the number, strength and proximity of springs in the study area are unusual, as are the steep aqueduct gradients and the small number of intramural cisterns. The study presents the first interpretation of the urban water distribution network in various periods. The aqueduct network was prone to damage from earthquakes and landslides, and these factors, together with climate change, contributed to the stress on the distribution system reflected in changes to the network in the Byzantine period. None of the components of the system is unique; instead, the system planners preferred to stick with simple installation types. Unusually steep aqueduct gradients and elevation differences within the city required careful management, but it is unclear how this was achieved. The general adequacy of the available spring-fed supplies in the study area can be inferred from the notable lack of any provision for long-term storage. Variations in annual rainfall and the known seasonal variation in spring flows, however, mean that it was probably not possible to maintain continuous offtake year-round in the city without the assistance of storage installations, as was the case in many Roman cities in North Africa. Overall, the results present a picture of a water management system that was comprehensively planned and regulated in the Roman-Byzantine period. It was built with practicality and economy in mind and may have started in the pre-Roman period.

JWP post-doc studies have, to date, included Gerasa’s earthquake history, diachronic changes in settlement patterns, and a detailed diachronic evaluation of the ancient city’s monumental nymphaeum built in the 2^nd century CE. AMS ¹⁴C archaeometric research into the history of horizontal watermills in the Jarash district confirms the viability of this technique to provide terminus post quem construction dates. The majority of the dated watermills were constructed in the Middle Islamic period; however, several have possible fifth to seventh century AD construction dates and are among the earliest known in the southern Levant.

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