A short explanation and a comparisson by W.D. Schram MSc

Overview Introduction on Roman aqueducts Introduction about Persian qanats Comparison An example Differences Persian qanats and Roman aqueducts

Aqueducts: definition An aqueduct is a channel or pipeline to transport water over a greater distance, from a water source to its destination: often a city, sometimes a farm, factory or mill; there the water is distributed. Differences Persian qanats and Roman aqueducts

Aqueducts: basic elements Differences Persian qanats and Roman aqueducts

Aqueducts: tunnels A masonry channel inside a tunnel (Cave de Curé, Gier aqueduct, Lyon, France) Differences Persian qanats and Roman aqueducts

Aqueducts: bridges One of the bridges in an aqueduct of Perge (Turkey), fully covered with calcareous deposits Differences Persian qanats and Roman aqueducts

Aqueducts: arcade Two aqueduct channels (70 and 88 km long, mainly subterranean) on top of a series of arches (Rome, Italy) Differences Persian qanats and Roman aqueducts

Aqueducts: the users Local fountain (Gerasa, Jordan) Baths (reconstruction) (Xanten, Germany) Differences Persian qanats and Roman aqueducts

Roman aqueducts: some 1500 Differences Persian qanats and Roman aqueducts

Qanats: definition A qanat is a combination of - an infiltration gallery or mother well that collects water from an aquifer, and - an underground tunnel, connecting a series of vertical shafts, to transport water by gravity to the surface for direct consumption and / or irrigation. Differences Persian qanats and Roman aqueducts

Qanats: basic elements Differences Persian qanats and Roman aqueducts

Qanats: construction Muqanni Clay rings for reinforcements Differences Persian qanats and Roman aqueducts

Qanats: from the air Persepolis Differences Persian qanats and Roman aqueducts

Qanats: channel and shafts Qanat shaft (near Yazd) Shaft tops Differences Persian qanats and Roman aqueducts

Qanats : bridge One of the few qanat bridges. This one is from Kharanaq. Differences Persian qanats and Roman aqueducts

Qanats: distribution in Iran Differences Persian qanats and Roman aqueducts

Qanats: distribution worldwide Differences Persian qanats and Roman aqueducts

Qanats: in Europe ?? A water supply system in Walferdange (Luxemburg) with a stepped channel and access shafts Differences Persian qanats and Roman aqueducts

Qanats: the users Place to scoop water Water distribution Differences Persian qanats and Roman aqueducts

Side step: water storage Water storage site Entrance Differences Persian qanats and Roman aqueducts

Comparison 1: Physical Geography ElementPersian qanatRoman aqueduct 1a.Character of the terrainAlluvial fans in mountainous areas From mountainous to almost flat area’s 1b.ClimateMainly in arid regionsSemi-arid and wet area’s 1c.SourceMother well(s) in an aquiferExternal spring, river, lake; by exception a well or aquifer 1d.Type of sourceDelayed deliveryMainly instant delivery 1e.Place in the landscape100% subterraneanSome 20% above ground Differences Persian qanats and Roman aqueducts

Comparison 2: Technology ElementPersian qanatRoman aqueduct 2a.ConstructionSubterranean channel with shaftsMasonry channel or pipe, sometimes with manholes 2b.BuildersPaid specialists / specialistsSlave specialists, contractors, sometimes military personnel 2c.CourseAlmost straight lineSinuous, following the countour lines 2d.Works of artBy exception (bridges, subterrenean dams and mills) Bridges, tunnels, arcades, siphons 2e.DistributionSluice gates, timesharing systemsCastellae divisoria 2f.StorageOnly local, with modelst volumesNo, behind some large bath houses 2g.Surplus waterReused in other qanats at lower levelFlushing sewers and public toilets, fullers Differences Persian qanats and Roman aqueducts

Comparison 3: Societal ElementPersian qanatRoman aqueduct 3a.UsersFarmers and general public. By exception in private housing for cooling General public use and bath- houses. By exception industry, private individuals and farmers 3b.OwnershipIn cooperation (10 – 250 individuals). Sometimes rich individuals Public bodies, town councils 3c.FinanceMembers of the cooperationLocan maecenas, emporer, town council 3d.Status within society The only water source, essential for life, utilitarian Additional to existing sources, luxury, showcase of pride and power 3e.Present statusMany still in useAlmost all out of use, some reconstructed Differences Persian qanats and Roman aqueducts

Example: Hadrian’s aqueduct in Athens Differences Persian qanats and Roman aqueducts

Example The major factor applied to Hadrian’s aqueduct Differences Persian qanats and Roman aqueducts ElementAs with qanatsH aqRemarks SourceAquifer(s)+ CourseStraight-See the map UsersGeneral public and farmers +/-General public and baths OwnershipCooperation-City council StatusThe only source of water -Additionally to existing wells and springs

Conclusions 1. Hadrian’s work had some elements in common with a typical qanat, but it was an aqueduct 2. In general: Although there are some similarities, qanats and aqueducts are quite different water supply systems Why is this important? There is enough misunderstanding of the word qanat. Differences Persian qanats and Roman aqueducts

Problems ?! Tehran (2009 CE) Nonius Datus (150 CE) (Saldae, Algeria) Differences Persian qanats and Roman aqueducts