Analisis Kebutuhan Air Irigasi Menggunakan Software Cropwat 8.0 (Studi Kasus: Daerah Irigasi Sekampung Batanghari)

Abstract

The lack of irrigation water supply causes farmers in the downstream area of the irrigation flow to choose to plant secondary crops or clear the land. This also occurs in the Sekampung Batanghari Irrigation Area with a potential area of 9,634 ha. In analyzing water requirenment, Cropwat 8.0 software can be used as an alternative so that the calculation process becomes easier and maximized. This research aims to analyze irrigation water requirement, cropping patterns, and irrigation water supply. The data used in this study include rainfall data, weir discharge, and climatology covering the Sekampung Batanghari Irrigation Area, each for the last 10 (ten) years. The analysis carried out is to calculate discharge of the weir, effective rainfall, potential evapotranspiration, crop water requirements, cropping patterns, irrigation water supply schemes, and analyze water balance. The cropping pattern used is Paddy-Paddy-Palawija with corn as a secondary crop. The greatest value of water demand in December is 5.42 m³/s. The scheme of giving irrigation water to paddy field is carried out continuously with certain water discharge of 5 mm / day. The availability of water is declared sufficient after analyzing water demand in the first planting season, namely paddy covering 100% of the total potential area, the second planting season, namely paddy covering 75% and corn covering 25%, the third planting season, namely corn covering 20% of the total area.