ANALISIS KEBUTUHAN DEBIT AIR PADA DAERAH IRIGASI ALUE KEURENYAI KEC. BANDAR BARO

Abstract

This research examines the intake discharge requirements for the Alue Keurenyai irrigation system, covering a service area of 102 hectares. The primary goal is to optimize water distribution and ensure sustainable resource use for agricultural irrigation. The study utilizes methods such as rainfall data analysis, evapotranspiration calculation, and water demand estimation based on empirical models. Rainfall data collected from 2013 to 2022 by the Meteorological and Geophysical Agency in Lhokseumawe were analyzed to determine averages, return periods, and rainfall intensity. Statistical techniques were applied to process the hydrological data, including the Smirnov-Kolmogorov test and Gumbel Type I distribution. The Penman-modified method was employed to estimate potential evapotranspiration (ETo).

Key factors influencing water demand include evaporation, percolation, crop coefficients (based on FAO standards), and effective rainfall. The results reveal that the highest intake discharge, 0.169 m³/s, occurs during land preparation, requiring significant water for soil saturation and surface layer refilling. Intake discharge requirements vary throughout the year, ranging from 0.024 m³/s to 0.169 m³/s, highlighting the importance of seasonal planning.

The irrigation system's efficiency, assumed to be 65%, accounts for water losses in primary, secondary, and tertiary channels. Accurate calculations of intake discharge are crucial to avoid excessive water use or shortages. This study emphasizes the need for precise irrigation management strategies to balance agricultural water demand and resource sustainability.

Additionally, the study addresses the water requirements for rice cultivation, including land preparation, evaporation, and percolation losses by deriving essential hydrological and irrigation parameters. This research provides a practical foundation for effective irrigation planning in Alue Keurenyai, ensuring sustainable agricultural practices and efficient water utilization.