Kualitas Air pada Irigasi Subak di Bali
Authors: Saputra I Gede Dumia , Sumiyati Sumiyati , Sucipta I Nyoman 
Published: September 2020

Air irigasi sangat berpengaruh pada subak, oleh sebab itu perlu dilakukan pengukuran terhadap pencemaran yang terjadi agar kualitas air tersebut baik untuk subak. Penelitian ini bertujuan untuk mengetahui kualitas air pada irigasi subak di Bali dan dilaksanakan pada tanggal 09 April 2019 pada 9 Subak di 3 (tiga) kabupaten yang ada di Bali, yaitu Subak Air Sumbul, Yeh Anakan dan Air Satang berada di Kabupaten Jembrana, Subak Guama, Subak Selan Bawak dan Jatiluwih berada di Kabupaten Tabanan dan Subak Tegal Kauh Selat, Subak Tohpati dan Subak Bugbug berada di Kabupaten Karangasem. Penelitian ini merupakan penelitian lapangan dan laboratorium, dimana hasil yang didapatkan akan dibandingkan dengan baku mutu air Peraturan Gubernur Bali Nomor 16 tahun 2016 tanggal 14 maret 2016 kualitas air golongan IV. Pengambilan sampel dilakukan pada dua titik yaitu pada Saluran Inlet dan Outlet. Sempel diteliti berdasarkan parameter BOD, COD, DHL (Daya Hantar Listrik), pH, Nitrit (NO2), Fosfat (PO4), dan TDS (Total Padatan Terlarut). Hasil uji paling tinggi pada parameter BOD menunjukan angka 8,078 mg/L terdapat di saluran Inlet subak Selat, COD menunjukan angka 21,735 mg/L di saluran Inlet subak Selat, DHL menunjukan nilai 308 µmhos/cm ada pada saluran Inlet subak Guama dan Selan Bawak, pH menunjukan nilai pH 8,40 di saluran Inlet Subak Bugbug, Nitrit menunjukan angka 2,606 mg/L di saluran Outlet Subak Guama, Fosfat menunjukan nilai 0,214 mg/L disaluran Inlet Subak Guama, TDS menunjukan nilai 238 mg/L pada saluran Inlet dan Outlet Subak Guama. Hasil uji keseluruhan masih sesuai dengan baku mutu air irigasi golongan IV.

Irrigation water is very influential on subaks, therefore it is necessary to measure the pollution that occurs so that the water quality is good for subaks. This study aims to determine the quality of water in subak irrigation in Bali and was carried out on April 9, 2019 on 9 subaks in 3 (three) districts in Bali, namely Subak Air Sumbul, Yeh Anakan and Air Satang located in Jembrana Regency, Subak Guama , Subak Selan Bawak and Jatiluwih are in Tabanan Regency and Tegal Kauh Strait Subak, Tohpati Subak and Bugbug Subak are in Karangasem Regency. This research is a field and laboratory research, where the results obtained will be compared with the water quality standard Bali Governor Regulation Number 16 of 2016 dated March 14, 2016 water quality group IV. Sampling is done at two points, namely the Inlet and Outlet Channels. Seals were examined based on the parameters of BOD, COD, DHL (Electrical Conductivity), pH, Nitrite (NO2), Phosphate (PO4), and TDS (Total Dissolved Solids). The highest test results on the BOD parameter showed the figure of 8.078 mg/L was found in the subak Strait Inlet channel, COD showed the number 21.735 mg/L in the Strait subak Inlet channel, DHL showed the value of 308 µmhos/cm in the Guama subak channel and the Selan bawak channel, pH shows a pH value of 8.40 in the Bugbug Subak Inlet channel, Nitrite shows 2.606 mg/L in the Subak Guama Outlet channel, Phosphate shows a value of 0.214 mg/L in the Guama Subak Inlet channel, TDS shows a value of 238 mg/L in the Inlet and Outlet channels Subak Guama. Overall test results are still in accordance with Group IV irrigation water quality standards.