Deduru Oya reservoir project, a milestone for NWP farmers

by P. Krishnaswamy

The multi-purpose Deduru Oya Reservoir Project which is due to be commissioned in November this year will mark an important milestone in the life of the agricultural communities of the North Western Province (NWP), who time and again have faced hardships and livelihood problems due to changing weather patterns and failed seasonal rains.

The main dam of the Deduru Oya reservoir

Work nears completion

The radial gates of the spillway

The impounding of the reservoir of 75 MCM capacity will be completed in October this year with the process already been started, followed by the release water to the Right Bank and Left Bank canals immediately thereafter, Project Director Engineer B.A.S. Sunil Perera told the Sunday Observer.

Paddy lands in the Deduru Oya and the Mee Oya basins will come under cultivation in both seasons benefiting over 15,000 agricultural families while about 50,000 families will benefit from domestic water facilities, lift irrigation and extension of inland fisheries culture, Perera said.

The project is one more achievement under the ‘Mahinda Chintana’ concept on food security in the country. There has been a marked progress in the production of rice and other crops under the Mahaveli Development programs and other multi-purpose irrigation and water supply projects implemented under the concept.

Dry zone

The main problem hitherto faced by farmers in the Deduru Oya and Mee Oya basins is the non-availability of assured water supply for the agricultural areas since the basins are predominantly situated in the dry zone of the country. The water available with the rainfall and collected in the existing irrigation schemes is not sufficient for two-season cultivation.

Seventy percent of annual rainfall in the Deduru Oya catchment flows to the ocean without being used in any way to serve the needs of the local population. As a result an optimal level of agricultural development has not been achieved. The Deduru Oya Reservoir project, on completion, will resolve all these problems while bringing many more benefits, the Project Director said.

All major components of the projects, including the main bund, the LB sluice, the RB sluice, electro mechanical and civil works (concreting) of the spillway, the causeway and the Magalla RB extention (11 km) have been completed 100 percent while only little work remains to be completed on the RB transbasin canal (33 km) and LB transbasin canal ( 44 km), he said.

Issuing water to the Inginimitiya reservoir which part of the project will be in January 2015. On release of water to the Inginimitiya reservoir in the Anamaduwa area, the local agricultural communities will derive the same benefits, Perera said.

Private and state lands were acquired for the project, needing payment of huge amounts as compensation.

Over 6,200 private and state lands had to be acquired in the Divisional Secretariat areas of Maho, Maspotha, Ganewatte and Wariyapola and compensation has already been paid to 97.7 percent of the owners. The amount paid as compensation up to end of April 2014 is Rs.1602.4 Mn and the process of paying the remaining compensation amounts is in progress, the Project Director said.

Sixth largest river

Of the 600 families needing resettlement assistance, 582 families which represent 97 percent have already been resettled in Karuwalagwewa -Radawihediella, Kobeyigane-Thelhera Farm, Polmmana and Ganewatte-Petarweliya phased over a period of seven years from 2007 to 2013, Perera said.

Other salient features of the project as provided by the Project Director are:

The project site is located within the Maho, Wariyapola and Ganewaththa Divisional Secretariat areas in the Kurunegala district. Construction of the concrete spill structure and the hydro power station of 1.5 MW has been completed.

Deduru Oya is the sixth largest river in Sri Lanka which is about 142 km in length and has a water resource area of about 2,420 sq. km.

The objective of the project is to prevent about 1,000 billion sq. metres of water flowing out to the sea without being used for productive purposes.

History bears witness to the fact that during the reign of King Parakramabahu the Great, dams were built at three locations basing the Deduru Oya and the water was used for irrigation purposes. The Ministry of Power and Energy is in charge of the 1.5 megawatt power plant. The National Water Supply and Drainage Board has constructed the water treatment plant to provide drinking water to over 50,000 families. The canal which feeds the Inginimitiya reservoir is concrete-lined and its discharge capacity is 300 cubic feet per second.

Infrastructure facilities to the people of the Maho, Wariyapola Karuwalagaswewa and Ganewaththa Divisional Secretary divisions include road networks, electricity, schools and clean drinking water which will immensely contribute to the improvement of their quality of life.

Unique achievement

Everything, beginning from conducting the feasibility study to designing the various components of the reservoir construction, was done by engineers of the Irrigation Department and this is considered to be a unique achievement of the Sri Lankan engineers.

The project will invariably contribute to consolidating the national plan of food security in the country. It will attract a tourist flow to the project site and the surrounding settlement areas. Productivity of not only paddy but also other highland crops, including vegetables and fruits, will increase many fold contributing further to the socio-economic betterment of the agricultural families. The necessity of development programs for the benefit of the population of the dry zone and intermediary zones in Sri Lanka arose due to many reasons but mainly owing to the food security of the people. The lack of food security arose due to disruption of agrarian systems, land fragmentation, lack of irrigable land, indebtedness of the farmers and poor post-harvest technology. The backbone of the population of the dry zone and the intermediary zones of Sri Lanka is based on agriculture with almost 85 percent of them depending on it for their livelihood. Nearly two-thirds of the land area of the country comes under the dry zone, an area with low annual rainfall and pronounced dry season. The dry zone is mainly rural, with many households relying on agriculture for their livelihood.

However the contribution that agriculture makes to household income has been declining and poverty and unemployment have been on the rise. The development and improvement of the water resources in the dry zone is necessary to obtain the efficient and maximum use of the vastly available land resources of the area. Therefore, water storage and proper management for successful irrigated cropping is a prime requirement for agriculture development.

The projects had also contributed to rural development, health care services and socio-economic uplift of the local communities. The Deduru Oya multipurpose reservoir project is one more jewel in the chain of many such mega multi-purpose reservoir projects implemented under the ‘Mahinda Chintana'. Many more similar projects are under implementation in the country to ensure efficient and maximum use of the vastly available land resources and the improvement of the standard of live of the people.

By 2020, the irrigation sector will become a key driving force in agricultural development with the supply of water in adequate, equitable and reliable quantities and in a sustainable, efficient and eco-friendly manner.