The term “drainage” implies removal of a liquid. For drainage scientists, that liquid is water, while in medical sciences, the term may be used to refer to bodily fluids. In this context, Luthin [1
] considered “drainage” as a word with many meanings. For instance, it is possible to ascribe the drainage of an area to the network of its streams and surface waterways. However, in subsurface hydrology, the term “drainage” is used to indicate groundwater drainage or the seepage through an aquifer. As Oosterbaan [2
] pointed out, “when we limit ourselves to land drainage the term has still, many different meanings”. In addition, he underlines that the different perceptions may result in confusion “when specilasts are talking the subject of drainage, particularly if they come from various disciplines”, and he ends up concluding: “the different interpretations make it difficult to give an unambiguous definition of what “drainage”, “land drainage” or “agricultural land drainage” is.”
Here, our primary interest is agricultural drainage, and consequently, our attention is focused on the removal of excess water and materials from the farm to improve crop growth, involving the removal of dissolved salts from the soil by means of conduits or other water conveying devices. Moreover, according to the ICID (International Committee of Irrigation and Drainage) drainage is the removal of excess surface or groundwater from any area, naturally or by virtue of man-made surface or sub-surface conduits, has four main functions: creating well drained arable lands, preventing salinization of the soils, lowering of groundwater table and removal of accumulated salts or toxic elements
Characteristic examples of past drainage technologies and practices developed by our ancestors in several regions of the world are remarkably similar to the modern standards of drainage. We address the evolution of drainage, which took place in the major civilization of the past, and the methods and means used to drain the land are considered in a combined geographic and chronologic perspective. Insights into drainage technologies in antiquity, the medieval ages, and modern periods with their properties of durability, adaptability to the environment, and sustainability are prepared, as well as a review of water technologies in major civilizations. Following this synthesis is a timeline clarifying the hallmarks of agricultural drainage of the past 10,000 years. The scope of the article is not confined to the suggestion of what is known today about the act of drainage, related technologies, and their uses worldwide. Rather, this paper displays characteristic examples of drainage enterprises in selected fields, which chronologically extend from prehistorical times to the modern era and geographically from the Asia, Europe, and South America. Moreover, in the final section, we deal with the potential of our findings, including the vexing question of how the presented examples of drainage technologies and irrigation water management in the past hold the potential of becoming important for present and future developments in water engineering. We believe that this past experience in agricultural drainage is now underpinning modern achievements in water drainage engineering and is a good example of how the past is the key for the future.
During periods of low agricultural interest, small drainage work is accomplished, and study activity declines in these periods as well. Practices used in previous prosperous periods lie idle and are forgotten. Then, with a return to high agricultural interest, interest in agricultural water management and in particular drainage also resumes, but the old approaches have to be redeveloped. Luthin [1
] reported that the reason for this is that one frequently sees articles in “popular magazines describing one new method of drainage that has just been invented”; it may very well be a recycling of already known principles of drainage used previously during, say, the early Mesopotamian, Hellenic or Chinese civilizations. Today, we use land drainage worldwide, and it is criticized severely by some and recommended by others [4
]. Further, drainage technology has improved considerably, in parallel with the general scientific and technical progress of our civilization [5
]. Nonetheless, in this context, past knowledge of drainage constantly inspires innovative rethinking of future drainage strategies. As Luthin [1
] pointed out: “The drainage is maybeas old as the art of agriculture.” The earliest evidence for artificial water management (irrigation and drainage) from Iran is from around 4000 BC [6
]. In Mesopotamia, concerns over inefficient application of irrigation and on the cropping management of weed in some years prompted development of techniques to control the depths of the water table. Cultivation of the deep-rooted crops shoq (Proserpina stephanis) and agul (Alhagi maurorum) helped to achieve this control coupled with maintenance of a severe dry area that prevented the rise of salts via capillary movement [9
Moreover, as early as in the third millennium BC, drainage systems were installed in Ancient Egypt, China, and India [5
]. Archaeological investigations identified evidence of serious drainage problems that developed in irrigated areas; and many have argued that the major reason for the decline of some historical civilizations that relied on irrigation was their problems with heeding drainage hazards [10
]. For example, some historians believe that the Sumerian civilization fell due to poor irrigation and drainage management [11
]. Specifically, large-scale salinization made farmlands unproductive, and this contributed to the collapse of the Empire. However, there is some evidence that in irrigated lands, the need to have drainage systems and waterlogging control was understood in earlier times. Moreover, the first evidence of soil and water salinization control via leaching and construction of drainage systems in Iraq dates back to ca. 2400 BC.
Agriculture in Greece and the Aegean developed during Minoan and Mycenaean times. Here, profound developments in agriculture were responsible for increasing agricultural productivity and growth of populations. The Minoans in Crete and an unknown civilization in the Indus valley (Harappans) were probably the leaders in the development of drainage practices. In addition, some archeological evidence suggests that Incas and Mayans used subsurface drainage [12
Irrigation and probably drainage systems appeared in Minoan Crete during the Neopalatial period (ca. 1740–1450 BC) when an extended drought period prevailed [13
]. In addition, the impressive remnants of the Mycenaean hydraulic works at Lake Kopais in central Greece shows important land reclamation work of prehistoric Hellenic times. However, in spite of the minor and extended surveys of sites, the picture of ancient drainage efforts at Kopais remains ambiguous [14
There is some evidence of similar hydraulic technologies to facilitate urban water management developed by Minoans and Mycenaeans and the other civilizations such as Egyptians, Etruscans, Dorians, Archaic, and Classical Greece [15
]. Herodotus, a Greek historian of 5th century BC, based on priests’ information of that period, wrote (Herodotus II) about the drainage works that Min (also spelled Mena, Menes, Meni) (ca. 3200–3000 BC), the first king of a unified Egypt, raised to protect the city of Memphis from floods. Classical Greeks inherited the Minoan urban drainage technologies and extended them further, mainly through changing their scale from very small to very large and implementing them to rural and urban sectors. Subsequent Hellenic, Hellenistic, and Roman engagements with and refinement of water management took place to aid agricultural production and land reclamation throughout the ‘Hellenic speaking world’ and the Roman Empire. However, the importance of soil properties as a basis of drainage design and the advantages of using deep covered drains under certain circumstances was recognized during the Classical and Hellenistic period (ca. 480–67 BC). Allegedly, attempts at draining Lake Kopais commenced during the Hellenistic period, and thereafter, the Romans extended the scale of the hydraulic works in the region. Until recently, however, the practices developed by Hellenes and Romans saw only limited improvements.
In ancient China, irrigation, drainage, and controlling floods have a history dating to around 3000 BC [16
]. Initially, drainage engineering was probably for the sake of water conservation as part of the development of Northern China during the Pre-Qin Period (ca. 2000–221 BC). The central area of the alluvial plain at the lower reaches of the Yellow river (now the Henan and Shandong provinces) with flat terrain and abundant water was naturally the most suitable for agriculture. Dry farming in Northern China included tolerance to drought and drought-‘resistant’ crops like common milletand foxtail millet. In the Northern Wei dynasty (386–534 AD), the concept of a drainage channel system with reference to the large-scale waterlogging [17
] was considered in the Youzhou province (presently downstream of the Haihe river basin). In addition, during the period from 1122 BC to 220 AD, saline-alkali soils in Northern China and in the Wei-Ho Plain were ameliorated with the application of proper irrigation and drainage systems, via leaching, rice planting, and through silting from historical floods [18
During the Medieval period, marshes in England were drained to stabilize and increase agricultural production. These actions were not accepted by the fishermen and fowlers, who saw their livelihood threatened [4
]. Interest in drainage declined until the 19th century, when the activity was renewed in the USA and Europe. In the USA, early interest was not restricted to the development and the enhancement of agricultural production but also stressed human health concerns, such as the draining of Central Park in New York City in 1858 [4
A tile drainage system was implemented in 1620 in the Convent Garden at Maubeuge, France, but this event did not spur widespread adoption of the concept [1
]. After two centuries, however, in 1810, a similar project had its origin in England on the estate of Sir James Graham in Northumberland. During the 16th, 17th, and 18th centuries, drainage techniques spread throughout Europe, Russia [19
], and the USA [20
]. Early in the 19th century, the invention of the steam engine brought a considerable enhancement in pumping capacity, enabling the reclamation of some large lakes, like the 15,000 ha Haarlemmermeer located southwest of Amsterdam in the Netherlands in 1852 [21
]. Moreover, the abovementioned drainage project of Lake Kopais did not succeed until technological advancements of the 19th century were available.
According to Donnan [10
], in the 17th century, closed drains were introduced in England, and in 1810, clay tiles started to be used but by 1830 were replaced with concrete pipes made with Portland cement. The first mechanically manufactured production of drainpipes took place in England, and from there, it spread across Europe and into the USA by the mid-19th century [19
]. In 1890, excavating and trenching machines driven by steam engines made their advent, and in 1906, dragline machines made their appearance in the USA [22
]. In the 20th century, the appearance of fuel engines led to the development of high-speed installation techniques of subsurface drains with trenching or trenchless machines [23
]. In 1940, clay tiles gave way to thick walled, smooth, rigid plastic pipes, or bituminous fiber pipes [24
], later replaced by corrugated PVC and polyethylene tubing in the 1960s [21
For centuries, land drainage was a practice based on local experience, which gradually developed into an art with wider applicability. The theoretical development of the modern sciences of drainage may be considered to have started only 158 years ago in France under the direction of French engineering Henry Philibert Gaspard Darcy (1803–1858), who conducted column experiments [26
] that established what has become known as Darcy’s law. Based on Darcy’s law, drainage theories developed that allowed land drainage to become an important field of research. Although these theories form the basis of contemporary designs for agricultural land drainage systems even today, they cannot determine beforehand a unique theoretical solution for a specific land drainage problem. Thus, as Bos and Boers [21
] noted, “sound engineering judgment on the spot is still needed and will remain so”.
Rapid technological progress in the twentieth century created a disregard for past water technologies that were considered to be far behind contemporary ones. There is a great deal of unresolved problems related to drainage systems–past and present—and especially to those used in agricultural lands. For example, in the past, drainage systems were anticipated to function for a long life, though with few follow-up studies [24
], and with little consideration given to changes in future climate or farming practices. However, this will not be so in the years to come, because global warming and the greenhouse effect necessitate development of new approaches to a changed set of drainage issues. Therefore, the operating rules, the management policies, the planning principles, and the design criteria for new drainage systems should be re-examined. While climatic variability is expected to have significant impacts on drainage systems, there remains great uncertainty as to the climate impacts in the different geographic scales of interest and how these affect the drainage development process. Moreover, in developing countries, drainage development is often constrained because of the lack of public support policies, institutional frameworks, and professional cadres [27
Although drainage is a very important environmental topic and a main factor in water resource management, for many years, it has been a ‘forgotten agent’ in water resources management, because drainage is considered by some as simply “an expensive solution to bad irrigation practices”. However, this consideration overlooks the role of drainage control of shallow water tables (retention and removal of water) associated with water resources and environmental management. Consequently, drainage is a basic key in: (a) flood management, (b) securing farm productivity, and (c) improving local sanitary conditions [28
]. It is understood that land drainage and soil amelioration techniques are fundamental to efficient agriculture and the preservation of biodiversity. Next, we explore the evolution and process of the drainage from the earliest times to the present and the lessons learned from history to offer new solutions to water risk-management strategies in current agriculture.
7. Present Times (from 1900 to Today)
As the chapters above demonstrate, the practice of drainage of agricultural lands was known since prehistoric times but remained very limited until the second half of the 18th century when, as part of the rebirth of modern agriculture, improved drainage began to attract wider interest and application worldwide. As Stuyt et al. [123
] pointed out, “In Europe, the initial drainage (subsurface) were built at the beginning of the Christian period. However, this kind of drainage (subsurface) was more or less forgotten in the next centuries.”
The traditional drainpipes made from clay and concrete and drain envelopes made of organic materials or gravel were replaced by new drainage materials. The first clay drainpipe was used in England in 1810 [23
], and a horseshoe-shaped tile was the first form of clay tile drainage used in England. Cylindrical drainage pipes were first manufactured in England in 1810 by the gardener John Reade at the village of Horsemenden in Kent. His handmade tiles were a great improvement over the old brush and stone drains and proved more popular than horseshoe drains [101
Portland cement (concrete) was used to make drain tile for first time in 1830 [101
]. Later on, in 1845, Tomas Scragg invented a machine for extruding clay tiles, which reduced their price by about 70% [124
]. This led to an increase in their use [101
]. In the 19th century, from England, the mechanical production of drainpipes spread over Europe and to the USA [19
]. Concrete and clay pipes were used as field drainage systems until they practically became obsolete with the introduction of plastic pipes.
In the 1940s, rigid plastic and bituminous fiber pipes were introduced in the USA [126
]. In the 1960s and 1970s, perforated plastic pipes with smooth walls were applied as subsurface drainage systems. Corrugated plastic pipes made of polyvinyl chloride (PVC) and polyethylene (PE) were extended during 1960s [127
]. In the 1980s, corrugated PE and PVC pipes are considered to be the preferred standard, and the choice depended on the availability of the raw material and the price [127
Many attempts and experiments were carried out in order to find suitable envelope materials, such as industrial waste products and fibers (e.g., coconut, glass rock wool) [129
The evolution of drainage is the reason for the restraint of installation costs despite the sharply rising costs of labor and materials. Specifically, until the early 20th century, installation of drainage systems was done by individual farmers [103
]. Thus, drain systems were designed and constructed based on the local experience and conditions, and later, suitable adjustments followed where it was considered necessary [131
]. The invention of the trenching machines and specifically of the steam engine in the late 19th century contributed to the revolution of the drainage practices [4
]. In 1890, diggers and trenchers driven by steam engines appeared [21
], followed in 1906 by introduction of the dragline in the USA [22
]. According to Zijlstra [132
], drain installations were first mechanized in the USA around the 1920s. However, it was not in practice until the 1950s, and it was introduced in Europe in the early 1970s through the introduction of trenchless machines [128
]. Secondly, most machines used for drainage systems worldwide are so-called “trenchers” [128
The introduction of large-scale drainage systems began around the middle of the last century, when knowledge of drainage and salinity had acquired a solid theoretical basis. The theoretical development of the modern science of drainage may be considered to have started only 158 years ago in France under the direction of Henry Darcy, who conducted column experiments that established what has become known as Darcy’s law [26
Land reclamation and drainage received a scientific basis from around 1945 onwards. In 1940, Hooghoudt [133
] presented his well-known analytical approach to the flow of groundwater to drains, and many other researchers, e.g., Ernst [134
] and Kirkham [135
], turned their attention to this field. Moreover, they confirmed, improved, and extended Hooghoudt’s work and drainage formulae for steady and unsteady flow; and formulae for complicated multilayered aquifer systems were developed as well [131
Until the 1970s, there was a great distance, figuratively and literally, between the engineer in the practical condition and the computer models in the office [131
]. With the introduction of programmable pocket calculators and portable microcomputers which became available, as well as the appearance of user-friendly software, the situation rapidly changed from the 1980s onwards. All of these offered to every drainage engineer the opportunity to employ these powerful instruments in a direct interactive environment.
The increasing use of the computer modelsfor drainage design and the vast development of software drastically changed the traditional approach to engineering design. Specifically, computers were used for field surveys, data processing, groundwater modeling, drain spacing calculations, detailed design of drainage networks, including the preparation of maps, drawings, and cost estimates. In this way, computers made it possible to improve the speed and quality of drainage studies and designs. Moreover, the analysis of groundwater flow and the relative calculations of saltwater balance, which had previously been considered too complicated and too costly for manual execution, now became possible [131
In the previous century, alternative drainage techniques developed, which have proven effective, affordable, socially acceptable, and environmentally friendly because they caused no degradation of natural land and water resources. One of them is biodrainage, which is defined as ‘pumping of excess soil water using bio-energy through deep-rooted vegetation with high rate of transpiration’ [136
]. Interest in biodrainage is strong in Australia, China, India, Pakistan, the USA and some arid developing countries that see biodrainage as a low-cost option for combating waterlogging and salinization [137
]. Further development of this interesting topic is beyond the framework of the present article.
At present, the performance of drainage systems is not only shown from a crop production aspect, but also from an environmental aspect, namely: (a) within the drained area, environmental interest focuses on the salinity and diversity of plant growth, and (b) downstream of the area drained, environmental issues because of the disposal of the drainage system are effluent.
In semi-arid regions of Western USA, subsurface drainage design and installation peaked in the 1960s–1970s and practically ended during the 1990s. There have been few, if any agricultural subsurface drainage system contractors in the valley regions since that time, though a few small contractors continue to operate in the coastal regions of the west. This roughly coincided with the final revision of the USBR Drainage Manual [138
] that compiled applied research towards subsurface drainage system design from the previous three decades. Typically, in dry regions, agricultural subsurface drainage systems were designed primarily for the management of root zone salinity that accumulated from irrigation. With increasingly limited options for ultimate disposal of the often-saline subsurface drainage water, installation ceased, and research re-examined the water quality aspects of subsurface drainage system design [139
]. These efforts suggested that drainage system design should consider installation and management methods directed at reducing subsurface drainage system flows and encouragement of crop water use of the shallow water table when and where possible. If combined irrigation–drainage system management was not possible, the collected subsurface drainage water could be used to irrigate progressively more salt-tolerant crops and finally dispose of them through evaporation from salt ponds or develop them as an alternative irrigation water supply [143
]. Finally, while previously drained lands were fallowed due to lack of subsurface drainage water disposal options, and competition for limited water supplies persisted, research and efforts in California have been directed at developing subsurface drainage water as a possible water supply (e.g., [142
In summary, in the past 60 years, a rapid increase has been taken into account in installation methods and drainage materials (such as pipes and envelopes). Specifically, subsurface drainage techniques were modernized more through innovative studies and development from 1960 to 1975 than during the past century.
Considering the exponential population growth on the planet [144
], the request for greater food and consequently the need for an agricultural drainage evolution should be considered [145
During the last 30 years and particularly the 21st century, new topics such as best management practices (BMP) [146
], smart drainage [147
], automated drainage [148
], and sustainable drainage [149
] have been considered to address the challenges regarding climate change and environmental issues to meet sustainable development in future [151
In the Appendix A
, a timeline of the historical development of drainage of agricultural lands has been presented.
8. Discussion and Conclusions
The state-of-the-art holds that adequate drainage improves soil structure and increase and perpetuates the productivity of soils. For example, adequate drainage: (a) facilitates early plowing and planting; (b) lengthens the crop-growing season; (c) provides more available soil-water and nutrients by increasing the vadose-zone; (d) increases soil aeration; (e) decreases soil erosion and gullying by increasing soil filtration; (f) favors growth of soil microorganisms; (g) leaches excess salts from the soil; and (h) assures higher soil temperature.
The worst farmers cannot desolate agricultural land if there is a proper drainage system. In addition, the best farmers cannot help to improve the soil’s condition if there is no proper drainage system. For instance, Adams [30
] explained the collapse of Mesopotamian city-states in the 1st millennium BC as the outcome of episodic political catastrophes and absence/change/in the Mesopotamian alluvium deposits from Euphrates and Tigris. In this area, and especially in Khuzestan and Western Iraq [9
], agricultural intensification and excessive irrigation without drainage systems led to reduced harvests, with developing prosperity, security, and stability. In the following years, though, the rise of saline groundwater eroded or destroyed agricultural productivity, and thus stability [158
]. Whole civilizations had collapsed due to lack of drainage systems. Therefore, having information about challenges and opportunities of agricultural drainage systems is essential to prevent the mentioned problems and to achieve sustainable agricultural development in the future.
Irrigation and drainage of agricultural lands have been known in Egypt and Mesopotamia since ca. 5000 BC, when the water of the flooding Rivers Nile, Tigris, and Euphrates was diverted to the agricultural fields for a couple of months during the summer and autumn. The water was then drained into the river at the right moment in the growth cycle. Further, some archeological evidence suggests that pre-Columbian civilizations used subsurface drainage [12
]. The first evidence of modern civilization and use of artificial water management (irrigation and drainage) was observed in Iran before ca. 4000 BC [6
]. The other evidence belongs to Chogha Mish in Southwestern Iran (ca. 3400–2900 BC). In this region, drainage systems were formed of clay pipes and baked clay bricks [35
In addition to the Mesopotamian civilizations, Minoans in Crete and an unknown civilization in the Indus valley (Harappans) appear to have used drainage techniques since the early Bronze Age [55
]. These reclamation practices were further developed and extended in prehistorical times by the Mycenaean societies and thereafter to historical times.
The basic ‘economy’ of the Greek City-state (ca. 650–67 BC) rested on operational agricultural systems, which included techniques of drainage, irrigation, and terracing. Although dry-farming techniques remained dominant in various forms of cultivation, it has been suggested that intensive farming involving irrigation, drainage, and marginal land was a distinct hallmark of farming in some city-states from the 6th century onwards. It appears that massive drainage projects were begun at Metaponto in Magna Graecia, and projects were outlined at Eretria in the island of Euboea, and possibly also in the Aegean island of Delos. Further, marginal land in southernmost Attica was protected against torrential rain by drainage channels and construction of basins for overflow.
Romans contributed significantly to the advancement of water engineering and irrigation [46
]. They had sophisticated knowledge of hydrology and introduced horticulture in their agriculture system. There has been evidence of gardens and wells, and planting beds arranged in parallel and along a slope. During dry periods, water would have been transferred from the wells into the ditches to irrigate crops. Romans greatly increased the scale of drainage projects, inventing concrete (opus caementitium) pipes and building much longer drainage canals. Intensive agriculture was developed in order to feed the increased population at that period. Thus, drainage technology was extended to the Italian peninsula, to Britain, to North African regions, to Palestine, and elsewhere.
Recently, Valipour [159
] studied major problems and perspectives of drainage vs. waterlogging and salinity throughout the world. Compared to waterlogging, the rate of salinity problems was severely higher, and more research needs to be done in order to meet the challenges associated with this problem (Figure 12
). In India, although less than 10% of the cultivated areas have been equipped with drainage systems, 23% of studies on drainage originate from this country from 1972 to 2013. This volume of investigations has had two achievements: first, prevention of salinity, and second, reduction of waterlogging (more than 70%) in Indian agriculture; and similar results were demonstrated in Australia, the USA, and Pakistan. This shows clearly the need for more research on the relationship between drainage and irrigation systems in various regions of the world [159
Wichelns and Qadir [160
] stated that we can start to decrease the degree to which waterlogging and soil salinity impair productivity and decrease crop production by designing and implementing effective local solutions [160
The need of drainage in India was recognized in 1865 when initial reports on soil salinity appeared. In arid and semi-arid areas, salinity also develops as a result of increasing watertables, and undoubtedly, installation of subsurface drainage systems improving the aeration of root zones will further improve the quality of soil. In Eastern Rajasthan Upland, in India, hydraulic conductivity using filter was detected to be the highest, and entrance resistance was the lowest [161
In China, in the fifth year of Emperor Xianfeng’s reign of the Qing dynasty (1855), after re-channeling the Yellow River at Tongwaxiang of Henan to flow towards the north, downstream of the Huaihe River, it converged at the Yangtze River and flowed into the sea after passing through Lake Hongzel, causing even more serious waterlogging in the Lixia Lake Area at the east of Lake Hongzel. From 1914 to 1920, the first dredging planning of the Huaihe River of modern water conservancy in the charge of Zhang Jian, the Director of National Bureau of Water Conservancy, coincided with the thought of the Huainan drainage engineering system of Qiu Jun in the Ming dynasty to a certain extent. The main difference lay in that the engineering design of the latter is established on the basis of quantitative analysis of modern river hydrological parameters, such as flow and flow rate [162
At present, engineers typically consider a design period of hydrostructures of approximately 40–50 years, which is accossiated with economic and environmental considerations. It is difficult to infer the design principles of ancient people. Nevertheless, it is notable that several ancient hydraulic works, such as drainage systems, have operated for very long periods, sometimes until contemporary times. For example, the drainage system in the Lasithi plateau in the island of Crete has been in operation since the Venetian and probably since the Minoan times. There are also some investigations claiming that agricultural methods and particularly drainage systems employed in prehistoric times have a potential to serve as models for sustainable agriculture today [163
Application of drainage systems, particularly subsurface systems, as an intervention to reclaim the lands with the problem of waterlogging and/or salinity and to achieve sustainability of irrigated agriculture has been known since ancient times. The subsurface drainage systems could be evaluated based on hydraulic properties of enveloped materials, various drainage characteristics of soil, and assessment of drainage spacing equations for the disposal of effluent material. The evolution of agricultural land drainage methods through the past centuries up to the present could act as a guideline or to operationalize the drainage systems/canals in an effective and eco-friendly manner, and this could be applied in the future.