After in-depth research, we have a more comprehensive understanding of water harvesting and water management systems in the ancient arid regions of Sri Lanka. Of the 255 texts from the fifth century BC to the tenth century BC, we have succeeded in collating and analysing 837 of them, of which 625 are from inscriptions and 212 from chronicles.
In these records, we managed to geocode 40 and link 173 passages of text to the reign of a particular king. Happily, a total of 362 records refer to tanks or their structures, accounting for 43 of the total2%γ
The "Irrigation Grants" and "Irrigation Revenues" categories accounted for a larger share of all records, with 276 and 75 respectively, representing 33 per cent and 9 per cent of the total records.
In addition, there were 69 and 52 records in canal and irrigation management, respectively, accounting for 82% and 62%γThe spatial distribution of these records is generally consistent with the extent of the arid zone and the northern median zone.
Of all the regions, the Anuradhapura district has the highest information density of ancient water harvesting and management systems with 490 records. It is worth noting that the data show an uneven distribution throughout the survey period, with a clear peak in the second century AD.
The history of Sri Lanka began to be written in the fourth century BC. Countless written sources document socio-political, economic, and religious developments.
Rock inscriptions from the third century BC are the earliest comprehensive written evidence on the island, while Sri Lankan chronicles β Deepawamsa, Mahavamsa and Kurawamsa β were written from the fourth century AD, while also looking back to earlier years.
In the arid regions of Sri Lanka, ancient water harvesting and water management systems were implemented as early as 2,000 years ago. This system was mainly distributed in the northern, eastern and southern parts of the Central Highlands, which is now the North Central Province.
The north-central province is a tropical region with a seasonally arid climate and a particularly dry summer season, with an average annual precipitation of about 1,750 mm and a total of 1,290 mm of annual evaporation.
To solve this problem, a series of artificial reservoirs, known locally as wewa, were built along shallow river valleys to form waterfalls. These tanks are connected by channels and spillways, creating a complex water irrigation system that transports water along cascades for irrigation of interconnected farmland.
This system began in the 4th and 3rd centuries BC and reached its peak in the 12th century BC, where it is still widely used today. The importance and sustainability of these systems has been well documented in ancient texts, and there are still many ancient cisterns in use today, numbering as many as 10,000.
While researchers have recognized the value of these systems, further efforts are needed to systematically analyse the information provided by inscriptions and written sources on water harvesting and water management systems.
Brohier was one of the first scholars to realise the importance and history of ancient irrigation projects in Sri Lanka, and his outstanding achievement was to link the specific water tanks mentioned in the chronicles with the major irrigation works of the present day.
Leach published a landmark study in 1961 on the traditional village irrigation systems of Pur Eliya in north-central Sri Lanka, delving into the physical properties, environmental perspectives, and technical engineering aspects of these systems.
Different documents and inscriptions reveal the history of Sri Lanka for us. Among them, the unsung author wrote the Dipawamsa in the middle of the fourth century AD, the first written chronicle of the island, detailing the history of the country until the end of the reign of King Mahassan in 362 AD.
Originally written in Pali, hOldenberg translated it into English. In this study, we also refer to the second comprehensive chronicle, Mohawasa, the Great Chronicle of Sri Lanka, which is also written in Pali and translated into German by Geiger.
The Mohavansa is a historical book compiled by the Buddhist monk Mahanama, which is divided into two parts: the Mohavansa and the Kurawamsa.
The Mohavansa covers the period from 544 to 362 BC and is the first part of the history and consists of chapters 1 to 37, verses 50. And "Kuravamsa" is the second part of this history book.
The Qur'an is divided into two parts and compiled by different authors. Part 1, compiled by the Buddhist monk Damakit in the 12th century BC, covers the period from 362 BC to 1186 BC.
The second part, completed by an unknown author, records historical information from 1186 to 1333 AD.
In the 18th century, the Buddhist monk Tibatuwaf Sumangara compiled the third part of the Qur'an, covering chapters 90, verses 105 to 100, verse 292, detailing the period from 1333 to 1781 CE.
When evaluating Mohavansa as a historical document, we need to note that it contains a large number of mythological and literary elements. However, for the accuracy of the database, the records we have selected have been carefully selected to contain only core historical events related to ancient irrigation landscapes or water management systems.
An analysis of 275 texts from the fifth to the tenth century BC yielded 934 records of ancient irrigation activities. After deduplication, we retained 255 text paragraphs and 837 records, which were given a comprehensive overview and a study of the spatial distribution of time and space.
Of these, 40 records were successfully geocoded, and 173 passages of text could be chronologically linked to the reign of a particular king. Of the 625 records analysed, most are based on ancient inscriptions, of which 131 are of Churavamsa and 80 are of Mahavamsa.
Only one record was extracted from dip**amsa because there were two similar entries.
Genre of inscriptions: Inscriptions of the late Brahmi script (n = 330), which was widely used between the second and fourth centuries AD and accounts for the largest proportion of records.
In addition, there are 200 records of Early Brahmi scripts (3rd century BCE-1st century CE) and 23 records of Transitional Brahmi texts (5th-7th centuries CE).
In addition, 72 records are assigned to the early Sinhalese script, which dates back to between the eighth and tenth centuries CE.
Of the 362 records, 43 per cent mentioned tanks, ponds, dams or puddles and their associated structures (Table 1). At the same time, the "irrigation grants" category accounted for 33%, reaching 276 records; "Irrigation revenue" accounted for 9 per cent, with a total of 75 records.
In addition, 8% of the canal records and 6% of the records of the official notice of the law, with the former having 69 records and the latter having 52 records. Other categories related to irrigation are recorded in small quantities and can therefore be ignored.
The geographical distribution of the 625 records on water catchment and management systems is broadly consistent with the extent of the arid zone and the northern intermediate zone of Sri Lanka. However, Jaffna District is currently located in the northern part of the arid zone and has not been recorded.
Similarly, the wetlands located in the southwestern part of the island have not been recorded.
With 490 records, Anuradhapura, with 490 records, is the most information-intensive area for ancient water harvesting and water management systems, followed by Kurunagara district with 92 records.
Polonnaruwa district has 60 records. Within the jurisdiction of the ancient Rohana kingdom, there are 30 records each in the Ampala and Hambantota regions. Ancient water harvesting and management systems in other areas are recorded in fewer than 30 items.
In the Anuradhapura, Polonnaruwa, Kurunegara, and Hambantota districts, tank records accounted for the majority of the paperwork, followed by records of grants for irrigation works.
However, in Ampalai district, records of grants for irrigation works are more common than records for water tanks.
In the Polonnaruwa region, canal records are the third most important category related to ancient water harvesting and management systems. In contrast, in other regions such as Anuradhapura, Ampala, and Hambantota, irrigation taxes, shares, and revenue records are the third most popular theme.
In the two districts from south-east to south of Sri Lanka, there is no record of laws and official announcements. The occurrence of the script is uneven, with early Brahmi and late Brahmi scripts appearing in all regions, but no early Sinhala and transitional Brahmi writing inscriptions have been found in the Ampalai and Hambantota regions.
There are only two transitional Brahmi inscriptions in the database that relate to the Anuradhhapura region.
In the early history of Sri Lanka, scholars and monks were responsible for writing specific and limited classical texts and chronicles, and they were primarily concerned with the establishment of specific faiths, lineages, and ritual centers throughout the island.
Moreover, the chronicle texts are full of historical facts and myths that originated in North India, as well as stories of inventions and confrontations related to South India. Sri Lankan historiographical texts, despite their clear agendas, provide credible information on the development of ancient water catchment systems.
The hinterland of the ancient capital of Anuradhapura is identified as the center of this system and can be traced back to continuous transmission in the arid regions of Sri Lanka.
In the third century AD, Anuradhapura had already built a major tank in the catchment area of the Marwatuoya River to saturate the water supply. In the following centuries, successive rulers actively promoted the spread of such water supply systems in the area around Polonnaruwa in the catchment area of the Mahaweli River.
By the 8th century, two major water management system complexes had been established, serving Anuradhapura and Polonnaruwa. The two complexes are connected by canals, allowing water between the wetter catchment of the Mahaweli River and the catchment of the Marvatuoya River to cross the catchment through the Kara River catchment.
In the ninth and tenth centuries, invaders from South India caused partial damage to water harvesting and water management infrastructure. At the same time, the administrative record of this period reached its peak, showing the strengthening and systematization of the bureaucratic structure.
While there is not much information available on small-scale community-driven village tank systems, it has been analyzed that Sri Lanka's ancient rural water harvesting and water management system may have evolved into a local community-based system that gradually evolved into an integrated watershed management system under the responsibility of the king.
This view is contrary to Carl Wittfogel's hydraulic hypothesis, which argues that Asian societies rely primarily on large-scale, state-controlled irrigation projects to achieve through the use of forced labor under the management of the bureaucracy.
However, in reality, Sri Lanka's arid regions have some ancient ways of managing and governing water resources based on local ecosystems that have stood the test of time and influenced colonial policies.
These include catchment ecosystems, village waterfalls and land and water management systems, and Sinhalese monastic buildings. These archaic ways show that people can effectively manage and use water resources even in the absence of modern technology and facilities.
Therefore, we need to pay more attention to and study these ancient ways to find more sustainable water management practices.