Download AQUEDUCTS, WATER SUPPLY AND CITY LIFE IN THE GREEK

AQUEDUCTS, WATER SUPPLY AND CITY LIFE IN THE GREEK AND ROMAN
WORLDS
Dr P.-L. Viollet1
Abstract: The classical Greco-Roman Antiquity used for water supply both the heritage of the
older civilizations of Antiquity, as well as new water technologies which appeared between
the IIIrd and the Ist century BC. Water had a high value, and the urban way of life was
characterized by abundance of water, for public service, pleasure, and industry, with
aqueducts, water distribution systems, baths, and water-mills.
Keywords: water management, aqueduct, fountain, water distribution, bath, water-mill.
INTRODUCTION
The Greco-roman world is often called “classical Antiquity” and it is the best known period
of Antiquity. It followed many centuries of older civilizations and previous urban
development which took place during the Bronze Age and to some extent inherited water
technologies from this age. The first section of the paper is a short analysis of this heritage,
and of the development of water technologies in Antiquity. The second section is related to
water distribution in Roman cities, with a focus upon Rome, Pompeii (Italy), Nimes (France),
and Petra (Jordan), a contrasting example. The third section is related to water use and
management inside cities in classical Antiquity.
HERITAGE IN WATER MANAGEMENT : FROM THE BRONZE AGE TO
CLASSICAL ANTIQUITY
During the Bronze Age, between the 4th millennium to 1150 BC, in the large interconnected
area situated between the Indus, the Nile and the Aegean Sea, water management technologies
developed up to a considerable extent, mostly for the needs of agriculture, with drainage and
irrigation works using gravity-driven open channels (Viollet, 2010). Cities developed, in
Mesopotamia, in Egypt, in the Indus valley (Harappean civilization), in Syria, in Crete
(Minoan civilization) and on the Greek mainland (Mycenaean civilization). The sources of
water for these early cities were (see table 1) : the large rivers or open channels derived from
it (Nile, Euphrates, Tigris, Orontes...), natural springs, wells, and structures allowing to
collect rainwater and to store it into cisterns. From the open channels, wells and cisterns,
water was not distributed, but carried by men or by women. Urban drainage conduits existed
in many of these cities. The aqueduct, defined as a manufactured long-distance conduit or
channel designed as to provide a city with water, for water distribution inside the city,
appeared only in the latest period of the Bronze Age, in Crete, and later in continental Greece.
The sophisticated water management in the palace of Cnossos (Minoan Crete), with an
aqueduct probably made with terracotta elements, baths, rainfall drainage and collection,
sewage conduits, may appear as the predecessor of the model of the use of water in the GrecoRoman cities.
1 Société Hydrotechnique de France.
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Table1. The sources of water in some Cities of the Bronze Age (3000-1150 BC).
Origine of the water
A short navigable canal connected to a large river
Canals allowing to direct floodwater into reservoirs
Gutters and cisterns for rainwater collection and
storage
Underground cistern fed from a spring or from
groundwater infiltration , with stairs allowing to
reach the water
Wells
Aqueduct or canal from a source in altitude
Cities
Uruk, Ur, Mari, Babylon (Mesopotamia),
Memphis (Egypt)
Jawa, Khirbet el Umbashi (Jordan, Syria)
Mari (Syria), Cnossos (Minoan Crete)
Mycenae, Athens, Tiryns (Mycenaean Greece),
Zakros (Minoan Crete)
Ugarit (Syria), Mohenjo Daro (Harapean Indus)
Cnossos*, Mallia* (Minoan Crete), Pylos,
Thebes (Mycenaean Greece), DurUntash (Elam)
* = probable
The Bronze Age civilizations came to an abrupt end by 1150 BC, under a series of troubles
which caused destruction of most cities of the eastern Mediterranean area (only Egypt
escaped). During the “dark age” which followed, writing was forgotten in Greece, until the
VIIIth century BC when the Greek alphabet appeared, derived from the Phoenician one, and
that the classical Greek civilization started. But the technologies of the great civilizations of
the Bronze Age, including dam construction, open channel flows design and construction,
terracotta pipes, remained. Those technologies were used in the classical Greek civilization
for aqueducts construction, urban drainage : Greek aqueducts were mostly made with
terracotta pipe elements ; they were generally buried and followed the slope of the land.
Water distribution inside the cities of this period is poorly documented.
The classical Greek period ends under the huge shadow of Alexander the Great who, in the
IVth century BC, conquered the eastern world between the Aegean Sea and the Indus River,
built Alexandria in Egypt, as well as many other cities. The eastern world and the western one
were set into contacts, and Alexandria became a key place for science and new technologies
including water technologies : pressure pipes, water-lifting machines (Archimedes’ screw,
Ctesibios pump, and bucket-chain). The water-mill (with vertical wheel) appeared somewhere
in the east during the Ist century BC. A key early example of an aqueduct using a pressure
pipe is the first aqueduct of Pergamon (Turkey), built in the IInd century BC, which used an 3
km long siphon with a pressure-pipe made of lead.
Then the Romans came, who inherited from Etruscan, Greek and Oriental civilizations and
developed the most outstanding aqueduct and water supply technologies, together with a real
water abundance. Water was now up to a large extent brought into the cities with aqueducts,
and distributed.
WATER SUPPLY AND DISTRIBUTION IN THE GRECO-ROMAN WORLD
A new model for city development
Cities of the classical Greco-roman Antiquity did not develop from a River as a source of
water, as it was the case in the Bronze Age cities of Egypt or Mesopotamia, but rather were
natural springs were available. The pure water from the spring has a high cultural value, often
in a religious manner, as local cults of nymphs are often related to the sources. When those
cities grow and when the available natural sources are not sufficient any longer due to the
growth of the population, then new sources are brought to the cities with aqueducts. This
scheme is quite evident in Rome, in Antioch (Syria), or in Nimes (Nemausus, France) for
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example. And when a new city is created, aqueducts construction goes together with the
building of the new town : this was the case in Lyon (Lugdunum, France), or in Carthage
(Cartago, Africa) after this city has been re-founded by Emperor Augustus. Monumental
fountains (see fig. 1), called nymphaea, are built either at the location of the original sources
in the city, or at the source of the aqueduct providing the city with water, or inside the city in
places where it can be fed in water by an aqueduct.
Fig 1. Two examples of monumental fountains. Left : the Peirene Fountain in Corinth (Greece).
Right : the Nymphaeum of Jerash (Gerasa , Jordan).
Roman aqueducts and their termination points inside the city.
The Roman aqueducts are masterpieces of civil engineering, many remains are still visible in
Europe, in Africa, and in the Middle East. Table 2 gives a few key examples.
Table 2.Characteristics of a few keynote Roman aqueducts
Country
City (roman name) / aqueduct
Length
(km)
Italy
Italy
France
France
France
Germany
Turkey
Tunisia
Rome / Aqua Marcia
Rome / Anio Novus
Lyon (Lugdunum) / aq. of the Gier
Lyon (Lugdunum) / Brevenne aq.
Nimes (Nemausus)
Köln (colonia Agrippina)
Pergamon (Pergamum) / Kaikos aq.
Carthage (Cartago) / Zaghouan aq.
91
87
86
70
50
95
50
118
Assumed
flow rate
(m3/day)
187000
189000
15000
10000
28000
27000
20000
17000
Within a city, water has to be distributed. A few is known from written sources and from
excavations in Roman cities. The aqueduct arrives in a reservoir (castellum aquae) which is
(with some exceptions) not intended to store water, but rather to distribute it within the
different circuits. According to the Roman architect Vitruvius, such a castellum should allow
to feed with the highest priority the public fountains, then the public monuments (baths,
gymnasiums), then the private people ; so that in case of drought the public fountains would
always be fed. Only few such Roman castellum have been preserved. The castellum found in
Pompeii (fig.5), distributing water into 3 systems, might fit well with Vitruvius’ description,
although this correspondence is not proven. The castellum found in Nimes (fig.6) distributed
water to 10 circuits. From the excavations, it comes that the Roman distribution systems
included secondary distribution reservoirs, and used pipes made of lead (in Italy and southern
Europe), as well as wood (in northern Europe) or terracotta (in countries with earlier Greek
influence).
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The city of Rome
Rome developed by the VIth century BC from small villages close to the Tiber River, in a
place which was fed by natural sources. At the beginning, the first hydraulic engineering in
Rome was the construction of the cloaca maxima, as a drainage system (fig 2). It was covered
at the end of the VIth century, as its presence as an open channel was an obstacle to the
development of the City. It is only in 312 BC that it became necessary to build a first
aqueduct, the aqua Appia. New aqueducts were built following the increase of the population
of the city, reaching at the end of the development a number of 11 aqueducts (fig. 3), with a
total discharge estimated to about 1 million m3 (1 m3 / day / person !)
N
all
l
rina
Qui
Tib
l
na
mi
Vi
q.
er
n
A
ia
rv
e
S
w
An
io
a
ac
clo P
al
wall
im
a
in
Esquil
ma
x
Ca
pi
tol
e
tus
Ve
atin
ia
pp
A
ve
nt
in
Caelius
A
ua
q
A
a
rci
Aq. Ma
ll
Janicule
wa
Fig. 2. The city of Rome under
the Republic : the cloaca maxima,
which was primarily a drainage
canal allowing to drain the forum,
was covered in the VIth century
BC, and since that time has been
serving as a sewer. The figure
shows also the first aqueducts
which were built in order to
provide water to the growing city :
aqua Appia (312 BC), aqua Anio
Vetus (272 BC), aqua Marcia (144
BC). The Aqua Appia passes
underneath mount Aventin, while
the Aqua Marcia, which has a
higher elevation, arrives at Mont
Aventin through a siphon issuing
from the Caelius. (Reproduced
from Viollet, 2007)
brooks
Ancient swamp
Elevation > 20m
1 km
aqueducts
The story of the first 9 aqueducts is well known thanks to the book written by Sextus Julius
Frontinus, who was nominated by Emperor Nerva as curator aquarum (director for water) in
97 AC. According to Frontinus, there were in the City of Rome at his time 247 distribution
reservoirs, 39 monumental fountains, and 591 public fountains with basins. We also learn
from his book that :
- Following Frontinus’ directorate, most public fountain could be fed by at least 2 aqueducts,
keeping the continuity of the water service during maintenance works on one aqueduct.
- The quality of water was very important : the two aqueducts derived from the Anio river
delivered less limpid water, and that was taken into consideration regarding the use of water
(pure water was preferably delivered to fountains); aqua Marcia was considered as delivering
the best water ; the 11th aqueduct, aqua Alsietina (see next section) was not supposed to be
distributed to public fountains because of its poor quality.
- Authorization to deliver water to monuments or to some specific private houses was a
privilege granted by the Emperor.
- Water-men often used to deliver water to private users in a fraudulous way according to a
parallel market.
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Population (millions)
Water supply
(millions m3/day)
Appia
Julia
Virgo
Tepula
Marcia
0,4
Anio Vetus
0,8
Alexandrina
Trajana
population
1,2
Claudia
Anio Novus
1,6
0,8
0,4
0
300
0
-400
-300
-200
1,2
-100
0
BC
Years
100
200
AC
Fig.3. The increase of the water supply and of the population in Rome (from Viollet, 2007)
Fig 4. Water distribution in Pompeii, with a photo of a street
fountain and its distribution tower.
Pompeii
Pompeii, which was destroyed in 79 AC by an eruption of the volcano Vesuvius, shows a
good example of a Roman distribution system (fig 4). The castellum (fig. 5) was situated at
Porta Vesuvio, at the highest point of the city, and there were downstream secondary
distribution reservoirs and distribution towers. Those distribution towers were fitted with a
small reservoir, at the top the the tower, whose level made it possible to adjust the
downstream pressure at a constant level, and not to have too much pressure in the public
fountains (photo on fig. 4). The population in Pompeii was about 8000, and the daily water
supply provided by the aqueduct was about 6500 m3. The ordinary people used to go to the
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public fountains to take their water, while water was distributed to public or private baths, and
to some rich houses which had their own private fountain (Jansen, 2000).
Fig. 5. The castellum of Pompeii : left : outside view with the 3 exit orifices for water
distribution ; right : inside view showing how the flow was separated into 3 branches.
Nimes (Nemausus)
Nimes is another interesting example of a Roman distribution system (Veyrac, 2006). The
city was created in the VIth century BC, before Roman times, around a historical spring called
“The Fountain”, a perennial but not regular source of water (average flow 100 l/s, lower flow
in dry season). It was later nicely built as a nymphaeum in the Roman time. An aqueduct was
built by the middle of the Ist century AC, under Claudius. Its castellum (fig. 6) was built at the
altitude of 59 m, higher than the Fountain (51 m), allowing to provide water to a larger area of
the city. The number of inhabitants in the Roman period is estimated to 20 000. The flow
delivered by the aqueduct was probably about 28 000 m3/day. Either from the Fountain or
from the aqueduct, water was distributed through lead pipes to public or private fountains, to
baths (9 can be identified, there may have been more), to latrines. There were also some wells
in the city, as well as an important sewer system.
500 m
Th
Spring
Aqueduct
Castellum
Baths
Fountains &
basins
Castellum
The
Fountain
Th
Th
Th
Th
Th
Th
Th
Th
Fig. 6. Water in Nimes, with a
photo of the castellum.
Amphitheatre
Th
100 m
80 m
60 m
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Petra
A contrasting example is Petra (Jordan), which was the old capital of the Nabatean kingdom,
then, after 106 AC, became the capital of the Roman province of Arabia. There were in Petra
advanced systems of rainwater collection (fig. 7) and conservation into cisterns, an heritage of
older Oriental technologies. In addition to this extended system, 6 aqueducts were built in
order to carry water from distant springs to downtown. As the city was built inside a set of
narrow valleys, it has been also necessary to build a number of dams protecting the city from
flash floods.
Fig 7. A small canal for
rainwater collection, above
the monument so called the
soldier’s tom, in wadi Farasa
in Petra.
WATER INSIDE THE CITIES OF THE CLASSICAL ANTIQUITY
Water : a source of pleasure.
Water is of high cultural value in the Greco-roman world, as we have seen from the
monuments and local cults associated to it. A specific source of pleasure associated with
water are the baths, which existed in the Greek world but developed up to a considerable
extent from the beginning of the Roman imperial period (Manderscheid, 2000). The
architecture of Roman baths became also more sophisticated. There is no doubt that the
development of aqueducts made the development of public baths possible, and that the
societal demand for baths probably contributed to justify the need of new aqueducts. But
aqueducts were not the sole source of water for baths : wells, cisterns, springs have also been
identified as sources of water to some Greek or Roman baths. In Cosa (Italy), water for the
public baths was lifted using a bucket-chain system.
A specific use of water as a pleasure was the nautical games (naumachia). In Rome, Emperor
Augustus made constructed a specific area for such games, on the right bank of the Tiber, and
an aqueduct (aqua Alsietina) was specially built in order to provide water for this area.
Water : a source for industry
Water is also used by industrial activities. A special interest is to be paid to water-mills. The
(vertical wheel) water-mill appeared in the Ist century BC, and developed rapidly inside the
Roman Empire, becoming a widely-used technology from the Ist century AC (Viollet, 2005).
The Roman water-mills often used aqueducts as the source of water. Many mills were in
private villas in the countryside, close to the source of grain. One astounding water-mill with
16 wheels was built in Barbegal (close to Arles, France), using a branch of the aqueduct
providing Arles (Arelate) with water. But there were also many water-mills inside the cities :
in Rome, there was in the IIIrd century AC a water-mill in the basement of the Caracalla baths,
and there were water-mills on the Janiculus hill, on the right bank of the Tiber, using water
from the aqueduct aqua Trajana, and possibly also from Aqua Alsietina. The development of
water-mills inside Rome is probably associated with the fact that, from the IIIrd century, flour
and no longer grain, was distributed to the population of Rome. Then grinding grain became
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under public responsibility. Water-mills existed also in the Vth century AC on the Roman
agora of Athens (fig. 8).
Water management inside the cities
The abundance of water created in many cities was also used the clean the sewer systems, and
to improve hygiene with public latrines fed with water (fig. 9). The large monuments like
amphitheatres were equipped with well-designed water-drainage systems. Also, as stated
above, many cities in the Mediterranean area were equipped with advanced systems for
rainwater collection and storage in cisterns (fig. 10).
Fig 8. Remains of a water-mill on the
Roman agora of Athens.
Fig. 9.
Public toilets in Corinth (Greece)
Fig 10. A cistern fed from rainwater in the
Nabatean city of Auara, founded in the Ist century
BC by Nabatean king Aretas III (Humeyna,
Jordanie). This city in the desert used to be an
important centre on the road from Petra to the Red
Sea.
All photographs in the present paper are from the author.
REFERENCES
Frontinus, De Aquaeductu Urbis Romae, Latin text with translation into French with
comments by P. Grimal, Les Belles Lettres (1961)
Jansen, G. 2000 “Urban water transport and distribution”, in Handbook of Ancient Water
Technology, O. Wikander ed., Brill, p. 103-125
Manderscheid, H. 2000 “The water management of Greek and Roman baths”, in Handbook of
Ancient Water Technology, O. Wikander ed., Brill, p. 467-535
Veyrac, A., 2006, Nîmes romaine et l’eau, CNRS éditions, Paris
Viollet, P.-L., 2005, Histoire de l’énergie hydraulique, Presses des Ponts et Chaussées, Paris
Viollet, P.-L., 2007, Water engineering in ancient civilizations, translated by F. Holly, IAHR,
Madrid
Viollet, P.-L., 2010, “Water Engineering and Management in the Early Bronze Age
civilizations”, in Water Engineering and Management through time – learning from
history, E. Cabrera & F. Arregui ed., CRC Press/Balkema, p. 27-54
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