SIMULATION SUBAK MANAGEMENT FUNCTION OPTIMALLY IN SUBAK LODTUNDUH, BALI, INDONESIA

Subak system has a very important role in agriculture development in Bali, especially on irrigation lands. Subak system with Tri Hita Karana (THK) philosophy has an opportunity to be transformed into other areas, as long as technology equity could be fulfilled. Optimal management of subak function is needed for such transformation, therefore this study aims to develop optimal management of subak function using analyses of linear program. The object of this study was Subak Lodtunduh, located in the upstream region of Kedewatan Irrigation Area, Gianyar, Bali. This subak was purposely choiced as its fuction works normally. Parameters of subak function management were determined by collecting primary data such as allocation, distribution, and water irrigation loan; subak facilities’ maintenance; conflicts resolution; ritual activities; output and input of production, cost of production, applied areas, and household labor supply; while the secondary data collected include irrigation volume and climate conditions. Results showed that Subak Lodtunduh optimally managed the subak function as its accomplished the five subak functions optimally during each planting season. These include (1) conducted allocation, distribution, and irrigation water loan; (2) maintened of subak facilities; (3) conflict resolution by conducting meetings on the early planting season; (4) conducting ritual activities; and (5) managed of subak resources. Analyses of optimal subak functions resulted that water distribution proportionally (tektek) by using one inlet and one outlet methods could be transformed into other areas as long as the technology equity could be fulfilled. Keywords: subak function, optimal management, Bali