Deduru Oya Dam

The Deduru Oya Dam is an embankment dam built across the Deduru River in Kurunegala District of Sri Lanka. Built in 2014, the primary purpose of the dam is to retain for irrigation purposes approximately a billion cubic metres of water, which would otherwise flow out to sea. Site studies of the dam began in 2006 and construction started in 2008. It was ceremonially completed in 2014, with the presence of then President Mahinda Rajapaksa.



Site studies and design of the dam was done by engineers from the Ministry of Irrigation. The dam, which measures approximately 2400 m wide, creates the Deduru Oya Reservoir, which has a capacity of 75000000 m3. Water from the reservoir is used to irrigate approximately 11000 ha of farmland, while also powering a 1.5 megawatt hydroelectric power station, operated by the Ministry of Power and Energy.

In addition to the eight sluice gates, water from the reservoir is channelled from the reservoir (for irrigation) via three canals, namely the Left Canal, Central Canal, and the South Canal. The South Canal is a trans-basin concrete canal measuring 33 km, channelling water from the Deduru Oya Reservoir to the Inginimitiya Reservoir at a flow rate of 300 ft3/s.