OPTIMIZATION STUDY OF IRRIGATION WATER UTILIZATION WITH DYNAMIC PROGRAMMING IN IRRIGATION AREA SYSTEM OF KALIBAWANG, KULON PROGO REGENCY

• Main Author: Zahra Asy Syifa, Fathimatuz
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/36900
• Institution: Institut Teknologi Bandung

Food self-sufficiency is one of the government's targets. Agriculture is an important sector to support food self-sufficiency. Especially if it increases the population, then the need for food continues to grow. One of the arguments is that air scarcity has occurred in several regions. This is difficult to increase productivity of agricultural products. Creating good agriculture regardless of irrigation aspects. Regarding irrigation water and water needs are important in plantations. Kulon Progo Regency is one of the regency that approved to realize self-sufficiency in support of the government. The biggest irrigation area in Kulon Progo Regency is Kalibawang Irrigation Area (D.I) which has an area of 7209 ha. Kalibawang Irrigation Area System obtain water supply from the Progo River with Kalibawang and Sermo Reserves (Free Capture) channels. Kalibawang Irrigation Area System consists of 13 Irrigation Areas which are interrelated from upstream to downstream. The Irrigation Area is Kalibawang Irrigation Area (1446.72 Ha), Kayujaran Irrigation Area (236.28 Ha), Sadang Irrigation Area (93 Ha), Krengseng Irrigation Area (80 Ha), Penjalin Irrigation Area (40 Ha), Papah Irrigation Area (986 Ha), Jelog Irrigation Area (40 Ha), Tawang Irrigation Area (40 Ha), Nabin Irrigation Area (26 Ha), Clereng Irrigation Area (140 Ha), Brangkal Irrigation Area (29 Ha), Pengasih Irrigation Area (2021 Ha), Pekik Jamal Irrigation Area (645 Ha) . The problem that often occurs is that agricultural land cannot be used properly in the dry season. Reduced allocation of water caused by the river air flow that falls in the dry season, then the air flow in the irrigation channel and evaporation. This is due to the not yet optimal irrigation land obtained by the Irrigation Area. The Dynamic Program is a step to optimize multi-mount decision processes. One of the basic characteristics that characterizes a dynamic problem program is that the problem is divided into variables with variables. This can be applied to irrigation system networks, related to each irrigation area interrelated and interdependent between irrigation area with each other. The available water utilization is carried out to meet water needs in each irrigation area. So to increase the yield of agricultural land and yield in the D.I Kalibawang System, it can be done by optimization using dynamic programs and then making alternative planting schedules and cropping patterns. Regarding the purpose of this study is to calculate and analyze each irrigation area water in the Kalibawang Irrigation Area System, calculate and analyze the water requirements of each irrigation area contained in the Kalibawang Irrigation Area System, select and analyze each irrigation area's planting schedule related to the Kalibawang Irrigation Area System that provides benefits the maximum, calculating and analyzing the maximum planting area and farm income that can be obtained based on the planting schedule currently applied and based on the alternative planned planting schedule chosen. The results obtained in this study are rice planting intensity in the Kalibawang Irrigation Area System has 181%. Planting intensity (IP) of rice in the Kalibawang Irrigation Area System with the alternative planting plan selected was 199%. This value increased by 18%. Income from farms obtained in 13 (thirteen) irrigation areas included in the Irrigation Area System of Kalibawang with the current planting plan of Rp. 307,940,810,160.00 / year. While the results of farming income are obtained in 13 (thirteen) areas of contribution in the Kalibawang Irrigation Area System by using an alternative planting plan using the dynamic program method, the farming income obtained is Rp 316,385,507,715.80 / year.