Roman springs: Water supply in antiquity

The water supply of ancient cities was an essential part of their infrastructure. Thousands of people had to be supplied with fresh drinking water every day to enable Roman life as it was then. Water pipes (Latin: aquae ductus) were used to bring fresh water from springs and wells, both above and below ground, from outside to the settlements. These pipelines were carefully planned and constructed to meet the needs of the population and at the same time fulfil capacity and hygiene requirements. In order to transport water over long distances, they were often laid underground to protect them from tampering or contamination, as an attack on the water supply was often the easiest and most effective means of pressure for enemy armies.

The technical know-how involved the supply, storage and distribution of water, often with considerable structural and organisational effort. For the supply of fresh water (or the discharge of waste water), the gradient, water pressure and water volume always had to be taken into account. The technical details and the construction of aqueducts, such as the famous above-ground Pont du Gard in southern France, are described in detail by the Roman writers Vitruvius and Frontinus.

Clay water pipe © Landessammlungen NÖ, Archäologischer Park Carnuntum (Photo: N.Gail)

The chorobat, a type of large wooden spirit level, was used to level the water pipes. This instrument helped to calculate an even gradient of the water pipes to ensure a constant flow of water. Water was stored and distributed within the cities using complex systems of cisterns and distribution towers. In Carnuntum and other cities, the water supply system was designed in such a way that it would function even if individual inflows failed. Several fresh water pipes ran through the city wall into the city centre. The streets contained built-in fresh water and sewage pipes made of clay, wood and stone pipes. Water was drawn from public wells, which thus became important social meeting places, free of charge and unlimited, which indicates a well-organised public supply for the population. In addition to being used as drinking water, the water supplied to the town was also used for bathing facilities and handicraft businesses such as fullonicae.

In Carnuntum, water was channelled into the city from distant springs through brick-built underground canals. Some of these channels were made of recycled material, especially reused components (so-called spolia), as was discovered during excavations south of the civil town. A 170 metre long water pipe channel was uncovered there, the cover of which was made of old material. Within the city, lead pipes (fistulae) were often used for water distribution due to their easy workability and tightness.  Brick slab channels for the fresh water supply are also documented for the civil city, as the excavations in the southern area of the Villa Urbana have shown.

Water pipes made of clay and lead © Landessammlungen NÖ, Archäologischer Park Carnuntum (Photo: N.Gail)

In recent years, research has once again focussed on investigations into Carnuntum's water supply. During excavation work for an EVN-Wasser project in Petronell-Carnuntum in 2017, an ancient Roman water pipe was discovered at a depth of around seven metres. The 14-kilometre-long pipeline, built in the first half of the second century, supplied the Roman city of Carnuntum with drinking water and is still functional today. As part of the ‘Abensperg-Traun water pipeline’ research project, an intact pipeline in the western suburb of Carnuntum was investigated in 2019 and 2020 by the Society of Friends of Carnuntum and the province of Lower Austria in cooperation with the Federal Monuments Office. As the water pipe turned out to be in need of repair, the canal, which was covered with flat tiles and equipped with a vault, was documented and repaired. The pipeline runs at a depth of up to six metres and is even accessible. 
 

Aerial view by Hermann Schneider / Exterior and interior view of the water supply canal by Andreas Konecny

In addition to the uncovering of individual pipe sections, non-destructive investigations were carried out in Carnuntum as part of the ‘ArchPro Carnuntum’ project from 2012 to 2015, with one sub-project focussing specifically on the water supply.

Earlier investigations focussed on water pipes outside the city, military camps and excavation finds. This project is currently focussing on the central area of the civilian city, which has already provided additional insights into various aspects of water consumption and use in the city. Earlier excavations have already revealed a multi-phase water supply system: initially, water was supplied by wells until the end of the 1st and beginning of the 2nd century AD, when a local pipe network consisting of wooden pipes and seepage galleries was built. With the paving of the streets in the first half of the 2nd century, brick water pipes were added. Around 200 AD, new fresh water supply pipes were built for the Great Baths. In the 4th century, alternative water routes had to be found due to clogged old pipes. The water supply of the civil city is still a main focus of current archaeological research in Carnuntum. 

For more articles on Roman history, simply visit the page of our science magazine! 

Further reading on this text:

C. Gugl – M. Doneus, Zur Wasserversorgung der canabae legionis und des Legionslagers von Carnuntum, in: F. Humer – A. Konecny (Hrsg.), Römische Thermen – Forschung und Präsentation. Akten des internationalen Kolloquiums veranstaltet vom Archäologischen Park Carnuntum und der Gesellschaft der Freunde Carnuntums, 17.−18. September 2009 in der Kulturfabrik Hainburg (St. Pölten 2011) 107–120.

M. Teichmann – M. Wallner – E. Pollhammer – W. Neubauer, Hydrotechnik und Wassernutzung in der Zivilstadt von Carnuntum, Thiasos 11, 2022, 97–107

A. Nedelik – B. Petznek, Die Fernwasserleitung zum Legionslager Carnuntum. Auf den Spuren eines antiken Desasters, Römisches Österreich 40, 2017, 117–204