Water management model of Sei Teras fishpond irrigation area in the Central Kalimantan food estate program

This study aims to apply semi-technical irrigation technology as an intermediate plan before an advanced development of the Sei Teras fishpond Irrigation Area can be established. Results of the previous study show that the availability of saline and freshwater sources enables the Sei Teras fishpond irrigation area to be developed into a semi-intensive advanced cultivation level. This study evaluates an alternative scheme of fresh and saline water management, which enlarges channel capacity and introduces gates. The evaluation compares the alternative schemes of hydraulic and water quality performance against the existing conditions using the HEC-RAS. The boundary conditions for modelling are obtained from measurement and Secondary data of the previous studies. The measured data are salinity, tides, and channel flow velocity. The parameters being compared are the discharge capacity, tidal water level, and salinity. The evaluation points are located at the Primary and Secondary channels. The simulation results show that enlargement of the channel capacity can increase the discharge to 129,22% at the evaluation point, but no significant water level change. Furthermore, the salinity level can maintain the aquaculture requirement by assigning the gates. Therefore, the alternative development scheme of the pond irrigation system is feasible and supports shrimp cultivation.