The Evolution of Water Supply Technologies in Ancient Crete, Greece
E. G. Dialynas1
and Α. Ν. Angelakis2
1DIALYNAS SA., 73100 Chania, Greece, firstname.lastname@example.org
2Hellenic Union of Municipal Εnterprises for Water Supply and Sewerage and National Foundation for
Agricultural Research, Institute of Iraklion, 71307 Iraklion, Greece, email@example.com
The history of water supply engineering in Crete dates back more than ca.4,500 years. From the early Minoan period (ca. 2900-2300 B.C.) issues related to water supply were considered of great importance and have accordingly developed. The Minoans had wonderful water systems, such as those found in Knossos, Tylissos, Phaistos, and Zakros. These systems included aqueducts, cisterns, filtering systems, rainfall-harvesting systems, terracota pipes for water supply and fountains. Minoan hydraulic technologies were developed further during several stages of Greek civilization. New, more advanced water technologies were also invented there, with a peak in the Hellenistic period, during which they spread over a geographical area from Greece to India to the east and Egypt to the south. The Romans, whose empire replaced the Greek rule in most parts of this area, inherited the technologies and developed them further, thereby changing their application scale from small to large and implementing them to almost every large city. In addition to Minoan, Greek, and Roman water supply achievements, water technologies in Crete were further developed and improved during the Byzantine and Venetian periods and are the underpinning of modern achievements in water engineering and management practices. The long durability that they possessed enabled these technologies to pass to modern societies despite regressions that have occurred through the centuries (i.e. in the dark Ages).
Keywords: aqueducts; Byzantine period; cisterns; distribution systems; fountains; Hellenistic period; Minoan period; pipes; Venetian period; water supply systems; wells.
Minoan technological developments in water management principles and practices are not as well known as other achievements of the Minoan civilization, such as poetry, philosophy, sciences, politics, and visual arts. To put into a lucid perspective the ancient water aqueducts discussed in this paper, it is important to examine their relevance to modern times and to elucidate some lessons learned (Mays, 2010; Mays et al., 2007). The relevance of ancient works will be examined in terms of the evolution of technology, technological advances that were made, homeland security, and management principles. Archaeological and other forms of evidence indicate that, in the Bronze Age of Crete, advanced water management and sanitary techniques were practiced in several settlements. This period was called by the excavator, Sir Arthur Evans, of the “palace” at Knossos as Minoan after the legendary King Minos. Thus, Crete became the cradle of one of the most important civilizations of mankind and the first major civilization in Europe.
The advanced water distribution systems in various Minoan palaces and settlements are remarkable, because there is evidence that several water techniques were unknown before the Minoan era. These techniques include the construction and use of water supply systems, such as aqueducts, cisterns, wells, collection and distribution facilities, and fountains. The hydraulic and architectural function of the water supply systems in palaces and cities are regarded as one of the salient characteristics of the Minoan civilization. These systems were so advanced that they can be compared with the modern systems, which were established only in the second half of the 19th century in European and American cities (Angelakis et al., 2010).
The overall theme of this paper is not the exhaustive presentation of what is known today about hydraulic works, related technologies and their applications in water supply during in Crete since the Minoan era. It will present a number of characteristic paradigms in selected sites chronologically extended from early Minoan to the Ottoman periods. Most of those water supply technologies are characterized from their adequacy, wholeness, and compliance. In some of those, the achievements of the periods to support the hygienic and the functional requirements were so advanced that could be paralleled only to modern urban water systems that were implemented in the developed world only in the second half of the 19th century.
The Significance of Water Supply in Ancient Cretan Civilizations
The achievements in water supply technologies in ancient Crete, since the Minoan civilization were so advanced that they could be paralleled only to modern urban water systems that were developed in Europe and North America in the second half of the 19th century (Angelakis and Spyridakis, 1996). It should be noted that hydraulic technologies in ancient Greece are not limited to urban water systems. The progress in urban water supply was even more noteworthy, as witnessed by several aqueducts, cisterns, wells, and other water facilities discovered, including the famous Minoan aqueducts of Knossos and Tylissos, the cisterns of Zakros, Archanes, Myrtos-Pyrgos and Tylissos, the wells of Paleokastro, Zakros, and Itanos (e.g., Koutsoyiannis et al., 2008). These advanced Minoan technologies were expanded to the Greek mainland in later periods of the Greek civilization, i.e. in Mycenaean, Classical, Hellenistic and Roman periods (Angelakis et al., 2010).
Minoan Civilization (ca. 3200-1100 B. C.)
The island of Crete, Greece, was first inhabited shortly after ca. 6000 B.C. and within three thousand years, it had became the largest Neolithic settlement in the Aegean sea. During the Bronze Age, the Minoan civilization was developed and reached its culmination as the first Greek cultural miracle of the Aegean world. The Minoan and Mycenaean settlements (in Crete and the Peloponnesus, respectively) developed and applied various technologies for collecting, transporting and using water from rainfall, surface and ground resources (Angelakis et al., 2010; Koutsoyiannis et al., 2008). A great variety of remarkable developments have been marked in several stages of the Minoan civilization, a civilization that flourished during the Bronze Age in Crete. These included various scientific fields of water resources such as wells and ground-water hydrology, aqueducts, cisterns, water distribution and domestic water supply, construction and use of fountains, and even recreational uses of water.
Aqueducts. In ancient Crete, the technology of transporting water with aqueducts was very well developed, due to the mountainous terrain (Mays, 2007; Mays et al, 2007).
The Minoan inhabitants of Knossos depended partially on wells, and mostly on water provided by the Kairatos river to the east of the low hill of the palace, and on springs. However, indications suggest that originally the water supply system of the Knossos palace initially relied on the spring of Mavrokolybos (called so by Evans ) (Angelakis et al, 2007; Evans, 1921-1935; Graham, 1987). Minoan aqueducts are of two types: (a) the open/ natural gravity flow system and (b) the closed/ pressured pipe system (Angelakis et al., 2010).
Open/ natural gravity flow system. Patterns of the open type aqueducts are attested to near water springs, such as those at Mavrocolymbos in the Knossos area (Evans, 1921-1935). Mavrokolymbos was a pure limestone spring located at a distance of about 400 m southwest of the palace of Knossos (Fig. 1). Its original elevation was about 150 m, whereas Knossos lies at an elevation of 85 m above sea level. Below the spring, A. Evans found an aqueduct that falls into the open type category. With adjacent vertical carved slabs and a horizontal one with a channel in the middle used as a raceway, the structure was part of an aqueduct that facilitated the supply of water, transporting it from the spring to the palace area. During the time of Evans (early twentieth century) the spring was lower than the elevation of the palace, a fact that led him to the assumption that the original spring was located further up and that the water table had decreased after the Minoan period (Angelakis et al., 2010). Recent investigations suggest that Evans was correct since the original spring was indeed traced higher (Angelakis et al., 2007). The initial location of the spring could thus eliminate problems of gravity flow and friction towards the palace area (Fig. 1, justify). Terracotta devices used as water filters were connected with domestic water supply aqueducts and/or reservoirs for providing suitable quality water.
a) Closed/ pressured pipe system. The advanced urban water distribution system of the closed type in the Minoan palaces and settlements is very interesting. The evidence for it in Minoan Crete comes from the use of terracotta pipes, found at the palace of Knossos and Tylissos, along with several others, albeit in bad condition, at the palace of Phaistos and at Palaikastro, Gournia, Lykastos and Zakro (House B). Among them the best patterns are those of the palace at Knossos, belonging to the earliest middle period and at Tylissos, assigned to the earliest late period although an earlier date has also been proposed for it (Angelakis et al., 2005).
Figure 1. Minoan water transfer projects: The proposed course (A’- B) of the aqueduct at Knossos with higher spring elevation (Angelakis et al., 2007) (justify) and water supply pipes (terracotta pipe sections): cross section and dimensions (upper) and today view (down) (Koutsoyiannis et al., 2008) (right).
Hellenistic Period (ca. 323-67 B. C.)
During the succeeding Hellenistic period, impressive accomplishments were also achieved in hydraulics, such as in the construction and operation of aqueducts, cisterns, wells, water distribution systems, baths, toilets, and harbours. At this time, major political and economic changes occurred leading to further architectural development and urban beautification in which aqueducts played a major role (De Feo et al., 2010). The remarkable progress in science during the Hellenistic period also provided the technical expertise required. Hellenistic aqueducts normally used pipes rather than the Roman masonry conduits. Furthermore, following the time honored classical tradition, aqueducts continued to be subterranean for security reasons (inter alia, exposure to enemies in case of war) but also for protection from the endemic earthquakes that plague the region. This practice again contrasts Hellenistic technology with its later Roman counterpart, whose salient characteristic was the use of arches and aqueduct bridges (Mays et al., 2007).
Greek aqueducts generally operated by free surface flow. However, during the Hellenistic period, scientific progress in understanding hydrostatics and water and air pressure allowed the construction of inverted siphons at large scales (lengths of kilometers, hydraulic heads of hundreds of meters). Thus, Hellenistic engineers constructed inverted siphons to convey water across valleys in aqueducts of several cities including Eleutherna, Elyros, Lato, and other cities. Cisterns at Eleuthrna and Elyros are shown in Figure 2.
Figure 2.Cisterns at Eleuthrna (justify) and Elyros (right) (Copyright permission with A. N. Angelakis).
The Roman Period (ca. 67 B. C.- 330 A.D.)
The Romans built what may be justly called mega water supply systems including many magnificent structures. The advanced water and wastewater technologies developed in Minoan and Hellenistic Crete were expanded and improved during the Roman domination of the Greek world. The achievements of this era, which met the hygienic and functional requirements of ancient cities, were so advanced that they could only be compared to the modern urban water systems which developed in Europe and North America in the second half of the nineteenth century (Mays et al., 2007). It should be noted, moreover, that hydraulic technologies in ancient Greece were not limited to urban water and wastewater systems. The progress in the supply of urban water was even more astonishing, as numerous aqueducts, cisterns, wells, and other water facilities indicate (De Feo et al., 2010). The aqueducts by that time were no exception to the laws of physics. This is possibly best demonstrated at Lyttos, where the site is set on an elevated spur. The aqueduct of Lyttos was obliged to depart from the contours of the mountains to traverse the lower terrain towards the city, near the village of Teixos (Kelly, 2006). In Roman Crete there were several aqueducts: in Axos, Chersonesos, Iraklion (Foundana), Gortys (Fig. 7, justify), Kissamos, Lappa, Minoa (Acrotiri), and Mochlos. Also, several cisterns from Roman Crete have been found in Aptera (Fig. 7, right), Dictynna, Lappa, and Rhizenia. In Roman Crete fountains, aquaria, and other water related structures for recreation are known (i.e. Chersonesos).
Figure 7. Remains of the Gortys aqueduct (justify) and cistern in Aptera city (2900m3 ) (right) (Copyright permission with A. N. Angelakis).
The Byzantine Period (ca. 330- 1204 A.D.)
From 961 to 1204 A.D., Crete was a part of the Byzantine Empire. ‘Hantax’ was the headquarter of the Duke of Crete. During this period, the technologies applied for water supply of the cities were more or less the same with that applied in the Arabic period. In many cases, collecting rainwater from the roofs of the houses and other opened areas in cisterns and wells was a basic practice. Every house had a well like this and the richer people had their own drinking water tank. For example, the water supply in the city of Iraklion during the Arabic and the Byzantine years, which can be considered to be primitive when carefully examining the diachronic history of the area (Dialynas et al., 2006).
The Venetian period (ca. 1204- 1668 A.D.)
Examining a document from 1403 A.D., it is clear that the Duke of Crete is commanding the maintenance of the water tank of the Duke’s palace by stating the following: ‘…because the water in a high necessity for the palace and the family of the Duke of Crete’. In Iraklion, the Duke’s palace also used three nearby wells. Francesco Morosini, general forecaster those days, commanded the maintenance of all existing water tanks in the city. The city still suffered from severe water shortage. In 1629, Francesco Morosini stated that the biggest disadvantage of the city was the water shortage. In 1591, a special well expert was sent to the city from the Venetian Senate. In the period of 1612-1614, Francesco Morosini was named the Duke of the city (Dialynas et al., 2006). He was the first Venetian that gave much attention to the water supply issues. He led the constructions of a 15.64 km line from which the water was transferred from three surface springs in the area of Karydaki into the city centre. The constructions were huge and thousands of workers participated. Three major water bridges (Karidaki, Fortetsa, and Lazaretou) were constructed as well as many canals in the inside of the city walls. During the distance, the water flew underneath monasteries and through the fortress of Fortezza (Spanakis, 1981). Finally, the water was ending up in the city centre and was running out from the mouths of four marmoreal lions. All this construction was then called Morozini’s aqueduct. The water bridge at the area of Karydaki is shown in Figure 3 (Dialynas et al., 2006). Moreover, remarkable fountains were constructed at that time; some of which are still in use (i.e. Rimondi fountain in Venetian Rethymnon, Central fountain in Ano Viannos, and Priuli Fountain in Iraklion).
Figure 3. Morozini’s aqueduct: Water bridge at Karidaki (justify) and Morozini’s fountain in the city of Iraklion (Copyright permission with M. Nikiforakis, EFIAP).
The Ottoman Period (ca. 1669- 1898 A.D.)
For the Ottomans, water was connected with their religion. In Crete, during this era, the front of every Tzami had to be a water tap so that people could pray five times per day. Also excessive water was needed for the hammam, the hot water baths that was very popular those days. Generally, people of this era did not pay any attention to increasing the quantity of the water brought into the cities (i.e Iraklion, Rethymnon, and Chania); they just maintained and kept all the constructions that they found from the Venetians (Dialynas et al., 2006).
The Egyptian Period (ca. 1830-1840 A.D.)
The most known new hydraulic work developed by the Egyptians is the Fundana aqueduct through which water was transferred to Iraklion from Fundana, a typical karstic spring. It is at a distance of about 5-6 km from the Knossos palace and lies at an elevation of about 220m. Fundana appears to have been used for water supply purposes throughout the history of Iraklio (Strataridaki et al., 2009). It was probably used for the water supply of Knossos during the Roman period (ca. 2nd century A. B.). Also constructed at that time was the tunnel at Scalani of 1x2m2 cross section and 1150m in length. The water bridge at Agia Irini was constructed later on (ca. 1839) at the end of this period (Fig. 4).
Figure 4. Fundana aqueduct: remains of aqueduct in Skalani (justify) and water bridge in Agia Irini (right) (Copyright permission with M. Nikiforakis, EFIAP).
Many civilizations, which were great centers of power and culture, were built in locations that could not support the populations that developed (Mays, 2010). Today, we find ourselves in similar situations in many places around the world. How do we balance the mega water projects with the methods of traditional knowledge? Koutsoyuannis, et al. (2008) explored the legacies and lessons on urban water management learned from the ancient Greeks, especially from the ancient Cretans. They summarized the lessons learned: (a) the meaning of sustainability in modern times should be re-evaluated in light of ancient water management practices; (b) technological developments based on sound engineering principles can have extended useful lives; (c) security, with respect to water, is of critical importance in the sustainability of a population; and (d) in water-short areas, development of an effective water resources management program is essential.
The use of traditional knowledge does not directly apply techniques of the past but instead, “to understand the logic of this model of knowledge” (Laureano, 2006). Traditional knowledge allowed ancient societies to keep ecosystems in balance, and carry out outstanding technical, artistic, and architectural work that have been universally admired. The use of traditional knowledge has been able to renew and adapt itself. Traditional knowledge incorporates innovation in a dynamic fashion, subject to the test of a long term, achieving local and environmental sustainability (Mays, 2007). The ancients for the most part, lived in harmony with nature and their environment. Those that did not failed. The Cretan civilizations are a cogent paradigm. Their actions should be warnings to us.
Authors thanks Mr. D. S. Spyridakis for his editorial assistance.
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