Sistem alokasi air pada Daerah Irigasi Balung Kabupaten Jember menggunakan WEAP (Water Evaluation and Planning)

Abstract

The irrigation system is developed and managed to supply and regulate water allocation for agricultural land, such as the Balung Irrigation System which has service area of ​​± 5,242 ha. In the dry season, the Balung Irrigation System is not able to serve the requirement of irrigation water, especially in the downstream areas. This condition causes uneven water allocation, which has an impact on decreasing agricultural productivity. This study aims to design a pattern of water allocation in the Irrigation Area of ​​Balung, Jember Regency to obtain optimal agricultural yields. The optimization model of irrigation water allocation was conducted using the Water Evaluation and Planning (WEAP) program. Optimization of water allocation is designed based on the regulation of cropping patterns by considering climate conditions consisting of dry years, low rainfall years, normal rainfall years, and adequate rainfall years. The selection of optimal cropping patterns is analyzed based on the highest coverage results of WEAP output. The results showed that in the 4 seasons conditions that are normal rainfall years, wet years, dry years, and adequate years have mixed results. The average yield of coverage in 4 seasons before being optimized was 95.04%, after being optimized it increased by 1.217% to 95.67%. The average yield of post-harvest rice benefits in the 4 seasons before being optimized was Rp7.080,000 and after optimization increased by 5,12% to Rp7,468,750. The average profit of post-harvest palawija before being optimized was Rp8,713,116 and after optimization increased by 1.72% to Rp8,865,511.