STUDI EVALUASI KEBUTUHAN AIR SEKUNDER DAERAH IRIGASI GORI-GORI KABUPATEN BANGGAI SULAWESI TENGAH

Abstract

Among the various sources of freshwater found on land, rivers stand out for their role in collecting rainfall across a watershed, making them one of the most commonly relied-upon options for meeting human water needs. This study sets out to compare water demand against water availability — commonly termed the water balance — within the Sinorang irrigation scheme in Banggai Regency, drawing on discharge records from the Gandong monitoring post together with rainfall figures gathered around the Sinorang catchment. Discharge estimates were derived using the F.J. Mock rainfall-runoff approach. The findings show that, overall, flow through the tertiary irrigation channels during the dry season falls short of the scheme's actual water requirement; across nearly every season studied, including the driest months, inflow to the Sinorang Dam remains below total demand. The average discharge computed from rainfall data reached 1.05 m3/s, while the monitoring-post record indicated a somewhat higher average of 1.63 m3/s — both figures nevertheless still exceed the recorded average irrigation demand of 0.97 m3/s for the Sinorang scheme.