Renaissance of ancient hydraulic engineering glory in Malwathu Oya river basin | Sunday Observer

Renaissance of ancient hydraulic engineering glory in Malwathu Oya river basin

18 July, 2021
An Aerial View
An Aerial View

The ancient kings built major medium and small scale tanks mainly in the Dry Zone including the North Central Province for agricultural, domestic and drinking purposes. Today our tanks system is a world heritage showcasing unique and marvellous hydraulic engineering expertise. The irrigation work continuing to date since the 5th centuary B.C enabling to store 4,000 million cubic meters of water in 75 major tanks, 17 medium scale tanks come under the Irrigation Department whereas another 3,150 million cubic meters of water storage in the Mahaweli scheme’s reservoirs. In addition, around 30,000 minor tanks holding a huge quantity of water for the benefit of the people. However, the technology of our skillful ancestors stands quite advanced to the extent that it can’t be deciphered even by the modern science and technology.

According to our chronicles, king Pandukabaya built the first lake ‘Abayawewa’ and ‘Basawakkulama’ in fourth century B.C in the Malwathu Oya river basin. Taking after the ancient kings, the Irrigation department in the recent irrigation history has constructed huge reservation such as Udawalawa, Inginimitiya, Polpitiya, Moussakele, Norton, Lunugamvehera, Manara, Rajangane in addition to new reservoirs built by the Mahaweli Authority namely Kotmale, Randenigala, Rantambe, and Victoria making a turning point in our irrigation history. At present, the main ongoing irrigation projects are Lower Deduru Oya, Kalugal Oya, Morana, Wellassa Navod Oya, Mahagona, Godigamuwa, Willakandiya and Ellawala for completion of which the Government incurs an expenditure of Rs. 12,000 million.

Following the examples of kings

The Government has given top priority for resolving the acute drinking and irrigational water scarcity in Anuradhapura and Polonnaruwa districts. At Present the Horowpothanayan Oya reservoir (149,000 acre feet) has already been completed. This huge reservoir is used to provide ample drinking water to Anuradhapura North region, Trincomalle and Vavuniya areas. Also the work of two three mega water projects are under construction. They are JICA funded Anuradhapura North phase one and two and the Chinese funded Thambuttegama water supply scheme. Simultaneously the water sources for these projects such as Wahalkada, Mahakanadarawa and Angamuwa reservoirs are being modernised and renovated in addition to strengthening the feeding and distribution canal systems. It is evident that water has become enormous value for our drinking requirements, cultivation, health care environment and food security etc in view of the increasing population and decreasing forest cover.

By overlooking any of these values, we are at the risk of mismanaging the most precious water resources thus ushering ourselves in to a jeopardy. We are a country endowed with a unique history of hydraulic civilisation. However, it is the high time to live the impressive saying of king Parakramabahu such as “Not even a single drop of rain water must flow into the sea without being made useful for the mankind’’.

In this background, the continuously prolonged Lower Malwathu Oya reservoir construction since 1950 decade is now being realised. The construction works of the reservoir commenced in last March by the Irrigation Minister Chamal Rajapaksa. Before it from time to time three foundation stones were laid since 2013, the last being laid by the Good Governess Government’s Prime Minister Ranil Wickremesinghe, sans any further construction or development than laying the foundation in a grand ceremony.

It is learnt that in somewhere in 1959, a team of Russian Irrigational experts assisted by irrigation department had made a sketch of the construction location of the lower Malwathu Oya reservoir close to historic Thantirimalethen thickly forested. Even today it seems there are some extremist and racialist elements or groups arguing that Anuradhapura district gets less benefits than Mannar and Vavuniya districts from the project despite that the reservoir is located in Anuradhapura District.

Largest source for Anuradhapura

Once constructed, the proposed lower Malwathu Oya reservoir holding 169,000 acre feet water capacity will be the largest water source in Anuradhapura district. The lower Malwathu Oya reservoir is constructed by constructing a 3.6 km dam across Malwathu Oya at Bogoda Village situated within the close proximity of historic Thantirimale sacred zone. Malwathu Oya river (AraviAru) flowing via Anuradhapura District to join Mannar sea. According to the Irrigation Department information sources, Malwathu river has been identified as one of the heavily damaged 27 major rivers in the country due to unappreciated activities of humans.

Malwathu Oya river basin is the country’s second largest river basin next to Mahaweli holding a capacity of 3246 square feet. It is learnt that Nachchaduwa, Nuwarawewa, Tisawewa, Mahakanadarawa and Pavakkulam major tanks are situated within the Malwathu Oya basin. The estimated expenditure to be incurred for the completion of the lower Malwathu Oya multi purposes reservoir project is Rs.19,000 million.

The project Director Engineer Sanath Gunasena said ‘Daily News’ that after inauguration of the head works construction on April 21, 2021, earth dam construction works commenced with core trench excavation at the right bank side of the proposed dam. The right bank canal is 4 km in length whereas the left bank canal proceeds for 2 km. The annual water extraction requirement for drinking water with the consideration of future expansions in North Central and the North regions under NWSDB, after further research and investigations has been increased from earlier 12 MCM to 27.1 MCM.

The Project Director said that the emerging new Thantirimale town planning for the areas developed by the lower Malwathu Oya Multi-sector development project has been already commenced by the UDA. He said that parallel to the ongoing project construction, a massive tourism development promotion plan for Thantirimale as an attractive major tourism destination is being implemented by the Provincial Tourism Ministry. A reforestation plan is to be executed extending to about 800 hectares.

Submerging areas and welfare

A new museum will be constructed for preserving the movable ancient historic monuments located within the submerging area. We hope to commence the construction of the spill, right bank sluice right and left bank canals and the initial resettlement activities before the end of 2021 Project Director said. It is learnt that around 10,000 acres are submerged to the emerging reservoir and 244 families are required to be resettled with new housing and adequate alternative land facilities provided in addition to granting, compensation for them.

The tourism promotion component is planned taking in to consideration the historical heritage including archaeological values in Thantirimale area and the Wilpatthu National Park (138000 hectares) located adjoining Thantirimale. Under the tourism development, the existing Thantirimale side entrance to the National Park will be developed with the construction of new water resources close to the location for attracting animals, the main cynosure of the Wilpattu national park. It is envisaged that a number of villages in Thantirimale, Nelumwila, Thuppitiyawa Asgirikgama, Mahaehetuwewa, Grama Niladari divisions located in Mahawilachchiya and Nuwaragampalatha DS divisions get submerged to the reservoir. The alternative muddy land will be allocated in Thantirimale, Dematamalgama and Muthalikulam areas.

Those families being evacuated are expected to be resettled in Naranwila, Kaluwila, Hingurutenna, Dematamalgama, and Thantirimale divisions. Also thirteen minor irrigation tanks are submerging to the giant reservoir to accommodate it. The tanks are Eliyakudawewa, Eliyamahawewa, weliwewa, Puliyankulamawewa, Ruwanmaduwawewa, Ransikawewa, Kupputiyawawewa, Upatissagamawewa, Sinnorukandhawewa, Diyamathurawawewa, Kimbulwewa, Morahaswewa and Karambakulamawewa.

Under the proposed Lower Malwathu Oya multi sector reservoir project, the targets expected to be achieved are to provide sufficient water to cultivate 35,000 acres with paddy in Mannar district mainly under major tanks such as Giant tank and Akathimurippu districts. As well make Irrigational water available throughout -the year for cultivating nearly 3,000 acres in Thantirimale and the suburb. This includes a lift irrigation project catering to nearly 1,300 acres. In addition, a number of abandoned small tanks in the locality will get sufficient water for drinking and agriculture. According to the department information sources the provision of drinking water amounting to five million cubic metres to Anuradhapura North, Vavuniya and Mannar Districts, annually and generation of 4.68 giga watts hours electricity is among the other benefits being derived from the reservoir project.

However, the irrigation officials, public organisations including farmer organisations holding the view that in the implementation of the 60 years delayed Lower Malwathu Oya reservoir the lessons learnt from the Anuradhapura Yan Oya reservoir construction project shall be taken in to deepest consideration to avoid tug-of-wars among stakeholders red tape undue political influences highly problematic situation in allocation of alternative muddy and highland delays in lands acquisition and above all the disarray in assessment and the payment of compensation, to those who lost their properties cultivations in accommodating for the emergence of Yanoya reservoir (149,000 acre feet) of which although the project complete two years back a part of compensation to be settled to the farmers still pending.

Delays by former parties

Before the present Government practically intervened in the task of realisation of the Lower Malwathu Oya multi-purposes reservoir project on the instructions of President Gotabaya Rajapaksa, the predecessor Governments plan was to deviate from the Yanoya reservoir episode to accelerate the payment of land acquisition, provide the housing, demarcate the alternative muddy land and complete the compensation and start head work construction parallel to fulfillment of these perquisites.

However, it is reported that so far under the new setup land acquisition is pending no any permanent decision taken with regard to the mode of compensation and providing housing facilities and above all the Cabinet memorandum for soliciting the approval for the amended project proposals yet to be submitted by the Irrigation Ministry.

Anuradhapura Government Agent, who is the head of the steering committee for Lower Malwathu Oya multi - sector Development proj R.M. Wanniyanayake said Daily News that the President wanted to have the reservoir project completed without any unnecessary delay. “There are some lapses in some components including the Land acquisition due to certain discrepancies in surveying plans which has been now rectified steps are being taken to get the Gazette notice to empower 38(a) sub section in the Land Acquisition Act published as immediately as possible and also to process the compensation payment structure following the less complicate ‘Superlark’ procedure subject to the ministerial approval for the purpose of accelerating the settlement of compensation.

However, the Mahasangha and the public organisations urge the Government that the learnt lessons from the adjoining Yanoya reservoir project shall be adopted and followed to avoid many lapses short comings discrepancies still being experienced and prevailing in the Yan Oya project although the project is said to have been completed. They point out that even after the Yan Oya reservoir has been completed two years ago there are still nearly 350 farmer families whose compensation yet to be paid.

Also the forest conservation department has not released the full extent of its land (forest landscape) for demarcating and allocating alternative muddy and high land to those who were displaced for accommodating the Yan Oya reservoir (139,000 acre feet) nearly 07 years back. There is a public opinion that the resettlement, payment of compensation provision of housing and other infra structural facilities shall be finalised parallel to the head work construction of the lower Malwathu Oya reservior project to avoid any chaotic situation now seen within the Yanoya reservoir construction project.”

The Malwathu Oya river starting from the Ritigala area, has been flowing via Anuradhapura journeying nearly 140km to join the sea in Manna district.

For centuries no significant step has been taken to tap the giant water flow to address the acute drinking and agricultural water scarcity in Anuradhapura district and the suburb until after several attempts to starts the reservoir project,construction having ended in failure President Gotabhaya Rajapaksa heeding to the numerous requests and urging by Maha Sangha headed by Thanthirimale RajaMaha Viharadhipathi Ven. Thanthirimale Chandrarathana Nayaka Thera and the termer organisations directly intervened to implement the proposed lower Malwathu Oya multi sector reservoir project.

A senior Irrigation Engineer now retired who once actively participated in the disrupted initial stage of the (attempted) realisation of the proposed Malwathu Oya reservoir project under the Government of former President Mahinda Rajapaksa with Nimal Siripala de Silva leading Irrigation Ministry told Sunday Observer that “due to tug- of-wars among stake holding parties, various conceptual logics contradictory political interferences the commencement of the project didn’t become a reality and unnecessarily delayed for nearly 60 years.”

“A team of Russian experts in collaboration with local irrigation Engineers somewhere in 1959 had made a inspection tour at several major rivers. including, Mahaweli, Malwathu, Ma, Kelani Yan and they had after a thorough spot inspection submitted a sketch plan of the proposed lower Malwathu Oya reservoir to be constructed in Thanthirimale area. Unfortunately, the implementation of this particular project prolonged under several Government’s. During the monsoon rainy season from October to January the Malwathu Oya river carrying around 2,000,000-acre feet flood water without being utilised for any purposeful or productive project in to Mannarsea, per day.

However it is a good omen that even at a late stage the Lower Malwathu Oya reservoir project delayed for nearly six decades coming true”.. Wickramatilake emphasised.