Variation of Water Productivity in Paddy Cultivation within a Tank Cascade: A Case Study in Ulagalla, Sri Lanka

The village tank cascade systems are identified as an important invention of the hydraulic civilization of Sri Lanka. Water productivity is a widely used indicator to measure the performance of these types of systems. A combination of agronomic and socioeconomic factors acts as key elements influencing water productivity in paddy cultivation and its variation. The current study focused on variations and determinants of the upstream and downstream water productivity of a cascade. The study was carried out as a comparative study investigating how the factors affect upstream and downstream water productivity in paddy cultivation separately in the Ulagalla tank cascade system in dry zone Sri Lanka during the Maha and Yala seasons over the years 2019-2021. The study revealed water productivity in paddy cultivation of the upstream and the downstream Ulagalla tank cascade was at satisfactory levels with reference to global standards. Wildlife conflicts, water conservative methods, V 7 - Availability of agro wells, V 8 - Water head, V 9 - Command area, V 10 - Availability of lining in the field canal, V 11 - Length of the field canal, and U- Error term. V 7 - Availability of agro wells, V 8 - Water head, V 9 - Command area, V 10 - Availability of lining in the field canal, V 11 Length of the field canal, and U- Error term.