Central Engineering Consultancy Bureau (CECB) of Sri Lanka was entrusted to Carry out the Feasibility study of the Wee Oya Reservoir project (WORP) under the Climate Resilience Improvement Project (CRIP) implemented under the purview of the Ministry of Agriculture, Livestock Development, Irrigation and Fisheries and Aquatic Resources Development. Consultancy services cover the feasibility study for Wee Oya reservoir based on pre-feasibility study done by CRIP on Kelani basin. Main objectives of Wee Oya reservoir are controlling flood, which effects middle and lower Kelani basin, and augmenting drinking and industrial water supply in the Lower Kelani Basin during droughts. The secondary objective is harnessing possible hydro energy. The project area is located in Punugala, Yatiyantota area about 60km East of Colombo. The Wee Oya, which is an upper sub-basin of the Kelani River, is formed by joining number of streams draining from the Dolosbage mountain range. To form the Wee Oya reservoir, the Wee Oya is planned to be intercepted 60 m AMSL of river bed elevation near Malalpola by a dam to impound a multipurpose reservoir with a maximum FSL of 129 m AMSL. The area of the Wee Oya catchment upto the dam location is about 58 km2. Elevation in the catchment ranges from about 60 masl to 1200 masl.