Analysis of Irrigation Water Quality in Rice Fields in North Tanoyan Village, Lolayan District, Bolaang Mongondow Regency

Analisis Kualitas Air Irigasi Areal Persawahan Desa Tanoyan Utara Kecamatan Lolayan Kabupaten Bolaang Mongondow

Abstract

This study aims to determine the quality of irrigation water for rice fields in Tanoyan Utara Village based on the National Water Quality Standards in Government Regulation No. 22 of 2021 concerning the Implementation, Protection and Management of the Environment, Appendix VI for irrigating class III and IV crops. As well as Sodium Absorption Ratio (SAR) analysis according to Ayers and Westcot, 1985. This research was conducted for three months, from February to May 2025 in the village of North Tanoyan as the location of rice field irrigation water sampling. Samples consisted of three points of tertiary irrigation water channel locations determined using purposive sampling method. Data were obtained from in-situ measurements and laboratory analysis at BSPJI Manado. Parameters analyzed include temperature, total suspended solids (TSS), acidity degree (pH), cyanide (CN), mercury (Hg), sodium absorption ratio (SAR) which consists of sodium (Na), calcium (Ca) and magnesium (Mg) parameters.The analyzed results show that the quality of irrigation water for rice fields in Tanoyan Utara village based on PP No. 22 of 2021 appendix VI for the parameters Temperature, TSS, pH and Mercury still meet the requirements of river water quality standards and the like class III and IV designation for irrigating crops, while the Cyanide parameter has exceeded the required water quality standards in class III. The suitability of irrigation water quality based on the analysis of the Sodium Absorption Ratio value is < 10 which means it is still in very good criteria and suitable for irrigation according to Ayers & Wetscot, 1985.