Biodiversity Conservation and Research Circle of  Sri Lanka
It is said that the Sri Lankan government tries to implement water policies again. There is no argument to have the policies, strategies and activities to manage fresh water as a sustainable resource, to protect the water environment, and to meet current and future demand of living beings. But unfortunately according to previous experiences in 2009, 2011 and etc: All the water polices provided the pathway not to proper conservation and management of water in Sri Lanka but to price water. If the government truly wants to manage our water resource in sustainable manner they can find out wonderful evidence from the history how the ancient rulers did that.

Water and land was the foundation on which human habitation and their development revolved. The ancient Sri Lankan civilization developed around three main elements, namely the tank or reservoir (wewa), the village and the temple. The wewa provide the water recourses for production and consumption, the village provided the environment for habitation, and the temple the spiritual necessities for life. But water was a vital, yet scarce, resource of the ancient Sri Lankan Civilization. According to the historical evidence Sri Lankans have had several enthusiastic water conservation and management mechanisms to save and optimum utilize of limited water recourse.

We can divide these mechanisms into 5 categories:
1.    Ancient Reservoirs and  Channel System
2.    Tank Cascade Systems
3.    Improved Land use pattern for water conservation
4.    Implementing rules and regulations
5.    Cultural practices for water  conservation

Water is one of the main natural resources in Sri Lanka, and it is the main factor which contributes to the country’s economic development. Sri Lanka being an agricultural country, the irrigation has had a unique contribution towards country’s agro economy from history to this date. In spite of that the water resource has become a prominent source in industry, supply of services, consumption (drinking) as well as recreation activities and tourism and hydro power generation.

Ancient reservoirs and channel system is an enthusiastic part of water conservation in Sri Lanka. The Sinhalese were among the first to build completely artificial reservoirs to store water. According to the Inscriptional evidence our ancestors divided the reservoirs in to three categories by using the size, as Gamika waw, Dhana waw and Maha waw (Jethawanarama Inscription). The first tank was built by King Pandukabhaya who reigned from 437 to 367 BC. It is said that he had three tanks built, namely Abhaya wewa, Gamini wewa, and Jaya wewa, yet, presently; only one tank named Basawakkulama wewa can be identified. King Parakramabahu had built many tanks, including Parakrama samudraya still providing water for agriculture.

Many rulers of Sri Lanka contributed to the development and construction of tanks all over the Raja Rata. King Dathusena (459-477) constructed the massive Kala Wewa reservoir and the 54 mile-long Jaya Ganga or Yoda Ela which had supplied water to Tissa Wewa (307 BC). Governor Henry Ward once mentioned Minneriya Wewa is a successful creation to avoid seasonal variations and natural hardships face by the people in the area. Even today About 12,000 tanks have been spread in Dry Zone areas of which the extent ranges from 01 to 6,500 hectares supply water for people.

The Tank Cascade System (TCS) concept is another unique water conservation and management mechanism used by our ancestors. It can be defined as a connected series of tanks organized within minor or meso-catchments of the dry zone landscape. The tanks in these meso-catchments served to store, convey and utilize water from ephemeral rivulets. The modeling of TCS and return flow through paddy fields express that the seepage and percolation losses from a tank in a cascade system are considerably higher than the design seepage and percolation rates for small tanks. Some researchers showed the presence of an active constructed wetland, locally known as ‘Thaulla’ which plays a major role in decontaminating the water flow into the tanks. It appears that some aspects of the TCS design were developed to improve return flow and to control non-point pollution of the water supply.

We can identify a relationship between Land use pattern and water conservation in ancient Sri Lanka. According to the Tonigala inscription there were three seasons of harvest of crop during the year. They were known as “Pitadadahasa, Akalahasa and Madehasa’’. The earliest Sri Lankan settlers purposely avoided the areas of receiving heavy rainfall for their settlements. They do not touch the central hills for establishing their villages and the ancient people settled mainly in Dry zone of the country. Although the kingdom of Kandy changes this land use pattern for the purpose of security they also implemented very strict laws and regulations to protect the up country water shades. The regulations mainly based on forest conservation and deforestation was strictly prohibited during that period. The protected water shades of the each and every tanks and reservoirs known as Wewe tawulla for the purpose of water conservation.

Our ancestors used traditions, rules and regulations to conserve the water resource in Sri Lanka. The Bethma Sirith system is one of the traditions used to water conservation. It provided the guideline to limit acreage to cultivate in the ‘yaya’ according to the availability of water. Kanna meetings was another democratic system that evolved where all farmers met at the temple premises, at an auspicious time and fixed dates, for the first issue and last issue of water from the tank.

Farmers, unlike today, did not wait till the tank was full to cultivate. They prepared land long before and sowed paddy in the form of Kekulama. The Kondavattavan Pillar inscription records offences which were punishable relating to water management. For an offence connected with flooding of the fields a fine of two Akas (ancient currency) was levied. For an offence connected with ploughing a fine of a Kalavda (ancient currency) was levied. For an offence of having ploughed late a fine of five kalandas was levied. There were wel mudalis or wel vidanes during the Kandyan period We Badde Lekam for fixing rent for paddy where paddy stores existed and we kuliya was common in the Anuradhapura period. These officials were connected with water management in the ancient Sri Lanka.  Relationship between cultural practices and water conservation in ancient Sri Lanka is also noteworthy. According to the well-known historical concept of Wewai-Dagabai, there is first a Temple in a village and then a tank. The monk in the temple prepared auspicious times for the ploughing ceremony called ‘Wap magula’. Ploughing the land at the same time ensure the conservation of water and a better harvest. Pen Pidima or the offering of the fresh water of a tank to the Buddha and Gods and Diya kapeema were another cultural practice used by our ancestors.

According to the above fact we can identify how our ancestors conserve the water, the scared natural resource. Those practices have conservation, management, reduce, reuse and refuse aspects according to the requirement to handle the water. The great king Parakramabahu (1153 AD – 1186 AD) said, “Do not release even a drop of rain water to the sea without using”. Still we can use that manifesto as the key aspect of water policy to proper management and conservation for water in Sri Lanka, not sale water at price.