Optimasi Jaringan dan Evaluasi Dimensi Saluran Primer Irigasi Bangsalsari

Abstract

Bangsalsari Irrigation Network comprising 2 primary channels and 5 secondary ones of
Bedadung Irrigation District of Jember Regency East Java is watering 3.913-ha farm at present.
However, it has not had sufficient water to provide 11 villages with water due to some problems like
climate change, changes in growing area and insufficient  channel dimensions, so it cannot optimize the
service. This thesis aims to find out the reliable discharge, crop water demand, planting pattern plan, and
to evaluate the existing channel dimensions. The reliable required data were of discharge, rainfall, soil,
climatology, profit analysis per hectare, and actual dimension. To find out the water demand of crops in
dry season, relative factor, and relative area methods were applied. The optimization results in 19.69
liters/sec. the largest reliable discharge in December; 1.07 liters/sec. the smallest discharge in June; 1.93
liters/second/hectare the largest crop water demand for rice in November; 1.37 liters/second/hectare for
crops in April and 1.40 liters/second/hectare for sugarcane in April; the recommended planting pattern is
rice-rice-palawija at an increasing profit of Rp.3,881,155,825 from Rp.137,921,496,875; 10cm, 5cm,
10cm, 20cm, and 5cm additional height of water for Palaran, Gambirono, Keting,  Sukorejo, Utara, and
Gumelar respectively.