an introduction

This website on Roman aqueducts and related items is a joint effort of Cees Passchier (Mainz, Germany) and Wilke Schram (Utrecht, the Netherlands) Nearly all information is based on published literature and on our own observations. Photographs and drawings are our own unless indicated otherwise and may be used free only for non-commercial purposes and marked with the name(s) of the copyright owner(s): ©2004-2007 Cees W. Passchier and/or Wilke D. Schram

The information in these pages has been assembled from a large number of sources, some of which contain contradictory information. It is therefore impossible for us to know if all the information given is correct and up to date (except where we were able to visit the sites). We welcome any comments on errors or incomplete information, so that we can improve this site further. It is not so much our website, it belongs to all who are enthousiastic about roman aqueducts, architecture and engineering.


Last modified: July 2006 - Wilke D. Schram (

Overview A Roman aqueduct
Basic elements
  • sources
  • pipes
  • trenches
  • substructions
  • arcades
  • bridges
  • tunnels
  • manholes
Water sources
  • spring boxes & well intakes
  • infiltration galleries
  • river intakes
  • dams
  • levelling
  • channel: cross section
  • roofs
  • materials
  • opus caementicium
Basins / castella
  • collecting basin
  • settling basin
  • regulating basin
  • junction basin
  • stilling basin
  • distribution basin (Castellum divisorium)
  • siphons
  • steep chutes
  • crossings
Water in the town (in preparation)
Industrial applications (in preparation)
Drainage systems (in preparation)
The word Aqueduct in 19 languages (usefull when searching the web)
Basins / castella in Roman aqueducts
Drawings of basins / castella and other Roman waterworks in Roman aqueducts
Literature on 600 Roman aqueducts
The aqueduct bridge of one of the three aqueducts of Merida (Spain)
A part of a siphon of one of the four aqueducts of Lyon (France)
The arcade of the Aqua Claudia, one of the eleven aqueducts of Rome (Italy)
The 'specus' of the 95 kilometer long aqueduct of Cologne (Germany)

A Roman aqueduct

A (Roman) aqueduct was a large water supply system delivering water from a source (left) to a town (right), a villa or an industrial site.
© 2004 W.D. Schram

Terms in other languages

  1. source (in this case: infiltration gallery)
  2. steep chutes (in this case: dropshafts)
  3. settling tank
  4. tunnel and shafts (putei)
  5. covered trench
  6. aqueduct bridge
  7. (inverted) siphon
  8. substruction
  9. arcade
  10. distribution basin / castellum divisorium
  11. water distribution (in this case with (lead) pipes into the town)

Basic facts

1 roman foot (pes) 0,296 m
1 actus (=120 pes) 35,5 m
1 roman mile 1480 m (5000 feet)
Distance between manholes (putei)
Vitruvius 8,4,3 1 actus (120 Rf) 35,5 m
Plinius NH 31,31 2 actus (240 Rf) 71 m
Burdy Gier aq   72 - 77 m
Vitruvius 0,5 % (5 promille) Book VIII 6.1
Plinius 0,02 % (0,2 promille) NH 31.57
Mean 0,15 - 0,30 % Hodge1992

Basic elements

Source of the water

There are many ways to get (ground)water into an aqueduct. The most common ones are:
1. Spring boxes and Well intakes
seem te be the active and passive means to collect water in a rectangular chamber; the water was supplied through numerous splits or specially created, sometimes arched, openings. A single outlet discharges the water into the aqueduct conduit.
More drawings A well intake, start of the Sofia aqueduct (Bulgaria) Springbox at Noé, one of the branches of the aqueduct in Sens (France) The Klausbrunnen near Kallmuth, part of the Cologne aqueduct (Germany)
2. Infiltration galleries
Infiltration galleries were sections of aqueduct gallery, 20 - 100 m long which ran along a hill side to intercept the flow of water that trickled out of the splits in the wall into the gallery. At one side the water was collected into a settling basin to get rid of the debris and sediments: the start of the aqueduct.
More drawings Infiltration gallery and settling basin at Grüne Pütz, start of the Cologne aqueduct (Germany) Different types of infiltration areas in one system, Gigen (Bulgaria) Infiltration area near Miesenheim (Germany)
3. River intakes
A river as a source for an aqueduct was not very popular in Roman times

More drawings This river intake of the aqueduct op Segovia (Spain) is still in use Impression of the river intake of one of the many aqueducts of Vienne (France)
4. Dams
Springs were the commonest source for roman aqueducts. River intakes were used occasionally. Artificial created lakes as a source were rare although they could have been used to equilize the variations in the seasonal flow rates of the feeding spring(s)
More drawings General view on a Roman dam with spillover Two aqueducts of Merida (Spain) were fed by water from artificial Roman dams Hypothetical arrangement in the Gorge de Peirou, water for Glanum (France)


1. Levelling
Given the elementary means, materials en tools which were available, it is remarkeble to see the precision withwhich the Roman aqueducts were laid out. The mean gradient of a Roman aqueduct was something between 0,15 - 0,30 %. As far as we know the most applied leveling instruments were the chorobates and the groma.
Chorobates Groma Dioptra of Heron

2. Channel (cross section)
Terms in other languages

1 = trench
2 = foundation
3 = footing
4 = floor
5 = vault
6 = extrados
7 = intrados, soffit
8 = imprint of the formwork
9 = side wall
10= plaster
11= coating
12= quateround
13= concretion
14= aqueduct water

© 2004 W.D. Schram

3. Roofs
Different types of roofs of an aqueduct
GB: vaulted roof GB: gabled roof GB: corbelled roof GB: flat roof

©2004 W.D. Schram
Terms in other languages

4. Materials
Water was transported in an open channel or in specific cases in a pipe. The most applied materials were masonry, pipes of terracotta / earthenware, wood (to be traced by metal rings) and lead (as used in siphons and inside the towns)

5. Roman concrete: see Opus caementicium