A short explanation and a comparissonby W.D. Schram MSc

Overview

Introduction on Roman aqueductsIntroduction about Persian qanatsSpecial topicsComparison

Persian qanats and Roman aqueducts

Aqueducts: basic elements

Persian qanats and Roman aqueducts

Aqueducts: tunnel

Note: a masonry channel

inside a tunnel (Cave de Curé, Gier aqueduct, Lyon, France)

Persian qanats and Roman aqueducts

Aqueducts: bridges

The world known aqueduct bridge Pont du Gard, part of the aqueduct (50 km) of Nimes (France).

Also represented on a banknote of 5 euro

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)

Persian qanats and Roman aqueducts

The Roman empire

Persian qanats and Roman aqueducts

Aqueducts: some 750

Persian qanats and Roman aqueducts

Aqueducts: the usersLocal fountain (Gerasa, Jordan)

Baths (reconstruction)(Xanten, Germany)

Persian qanats and Roman aqueducts

Aqueducts: examples

Tunnel and pipes Akcay tunnel(550 BCE) (Side, Turkey) (Samos, Greece)

Water distribution(Pompeii, Italy)

Persian qanats and Roman aqueducts

Qanats: basic elements

Persian qanats and Roman aqueducts

Qanats: channel and shaftsQanat shaft (near Yazd) Shaft tops

Persian qanats and Roman aqueducts

Qanats: from the air

Persepolis

Persian qanats and Roman aqueducts

Qanats: the users Place to scoop water Water distribution

Persian qanats and Roman aqueducts

Qanats: works of artQanat bridge (Kharanaq, Yazd)

Ice house(Yazd)

Persian qanats and Roman aqueducts

Qanats: distribution worldwide

Persian qanats and Roman aqueducts

Qanats: distribution 1

Persian qanats and Roman aqueducts

Qanats: distribution 2Tehran (ca 1960 CE) Isfahan (1942 CE)

Persian qanats and Roman aqueducts

Qanats: distribution 3Tafilalt (Maroc) Qanats in Syria

Persian qanats and Roman aqueducts

Qanats: in Europe 1Madrid (Spain) = Madjira = place of qanats

Near Selb and Asch (Germany)

Persian qanats and Roman aqueducts

Qanats: in Europe 2The qanat of Walferdange (Luxemburg) with stepped channel and access shafts

Persian qanats and Roman aqueducts

Qanats: construction

Muqanni Clay rings for reinforcements

Persian qanats and Roman aqueducts

Storage Water storage site Entrance

Persian qanats and Roman aqueducts

CoolingWind towers Technique

Persian qanats and Roman aqueducts

Ice house Meybod Cross-section

Persian qanats and Roman aqueducts

Subterrenean damDam in a qanat (Vazvan) Cross-section

Persian qanats and Roman aqueducts

Subterranean water mill

Horizontal water wheel

Persian qanats and Roman aqueducts

Comparison 1Element Iranian qanat Roman aqueduct

Climate Mainly in arid regions In arid and semi-arid regions

Source Aquifer River, spring or dam (by exception: well or aquifer)

Place in the landscape

100% subterranean 20% above ground (arcades, substructions)

Construction Shafts every 50 – 100m plus connecting channel

Masonry channel (or pipe), sometimes in qanat construction (shaft every 35 – 70 m)

Course Straight line Sinuous, following the contour lines

Works of art Exceptional: subterranean dams

Bridges, tunnels, arcades, siphonsPersian qanats and Roman aqueducts

Comparison 2Element Iranian qanat Roman aqueduct

Users Public and farmers (private houses, bath houses?)

Public and bathhouses. Also: houses, farmers, ornamental fountains (grainmills)

Distribution Channels and sluices; for irrigation timesharing

Distribution stations plus lead pipes inside the towns

Status Utilitarian / lifeline Additional to other sources (wells, rainwater); luxury (Baths); showcase (Show of pride and power)

Builders Well paid specialists Slave specialist, contractors, sometimes support from the military

Ownership Coorperative ( 10 – 250 p)

Town councilPersian qanats and Roman aqueducts

Comparison 3Element Iranian qanat Roman aqueduct

Finance Members of the cooperation

Local meacenas, the emperor, twon council

Surplus water (only in winter): ? To flush the sewers and toilets, fullers

Storage Local in modest volumes

No, only behind some large bath houses (e.g. Rome)

Basics: - cross-section - typical length - typical discharge - typical depth - typical fall

0,6 – 1,2 m10 km2.000 m3/day10 – 50 m0,07 – 0,1 %

0,6 – 1,2 m20 km20.000 m3/day5 m0,1 – 0,5 %

Persian qanats and Roman aqueducts

Conclusions

Although there are similarities, qanats are quite different from roman aqueducts

Most striking: the difference in the sourcesqanat(s) are often the only source of waterRoman aqueducts are all out of use

Persian qanats and Roman aqueducts

Problems ?!Tehran (2009 CE)Nonius Datus (150

CE) (Saldae, Algeria)

Persian qanats and Roman aqueducts

Usefull websites

The International Center on Qanats and Historic Hydraulic Structures (ICQHS) in Yazd: http://www.icqhs.org/English/Default.aspx

The Water Museum in Yazd is part of the ICQHSYoutube film about qanats:

http://www.youtube.com/watch?v=ieBVMOPRYJ0

Persian qanats and Roman aqueducts

Thank you Wilke Schram