Optimization Model of Batutegi Reservoir Operation Pattern by Using the Simulation Method of Cropping Pattern for Obtaining the Economic Expected Value

Abstract

This research intends to manipulate the cropping pattern by moving the first cropping pattern schedule in the Batutegi reservoir due to the irrigation area of Way Sekampung being 55,373 ha. The methodology consists of manipulating the cropping patterns as the optimization result of the simulation model. The simulation is performed by analyzing the water balance, which is based on the water supply and demand. The existing condition results are as follows: the crop beginning in the middle of December 2018, the minimum reservoir volume is 107.55 million m3, the reservoir volume at the end of December 2019 is 172.56 million m3, which produces run-off in Argoguruh weir for the period of Dec 2018 until Dec 2019 to the amount of 232.16 million m3, and the maximum paddy harvest yield (GKG) is Rp. 3,777,800,000,000 per year. This research was carried out to manipulate 5 cropping pattern alternatives by using the water balance simulation method and considering the economic benefit. The results show that the cropping pattern alternative that produces the maximum economic benefit is as follow: the crop beginning in October 2018, the minimum reservoir volume is 130.00 million m3, the reservoir volume at the end December 2019 is 195.00 million m3, the run-off that is produced in Argoguruh weir for the period of December 2018 until December 2019 is in amount of 270.54 million m3, the maximum paddy harvest yield (GKG) in 2019 is Rp. 3,814,949,000,000 per year, and the benefit is Rp. 37,149,000,000 per-year or 1% of yearly production.