Water quality of the Panasen River in the upstream of the Tondano Watershed in a five-year period (2014-2018)

Water quality of the Panasen River in upstream of Tondano's watershed is important to study because the Panasen River crosses residential areas, agriculture, and livestock farms, carrying solid and liquid wastes from these activities, which ultimately leads to Lake Tondano. This waste has the potential to become residue in Lake Tondano. The objective of this research was to study water quality of the Panasen River in the upper of the Tondano watershed throughout a five-year period (2014-2018). Water sampling is done by using composite sampling in the one location of Panasen River which become the inlet of Lake Tondano, analyzed using Colorimetry method, and compared with the Quality Satndard in accordance with the Law of No. 82/2001 Class II about Water Quality Management and Water Pollution Control (KLH, 2001). The results showed that 30 parameters (temperature, pH, TDS, TSS, NH3, DO, BOD, COD, chloride, CN, F, NO3, NO2, sulfate, sulphide, PO4, As, B, Ba, Cd, Co, Cu, Fe, Mn, Pb, Se, Zn, Hg, Cr-VI, surfactant (MBAS)) analyzed generally met the Water Quality Standard in accordance with the Law of No. 82/2001, except the chlorine parameter concentrations: Chlorine concentration in 2013 (0,1 mg-0,19 mg/l), 2014 (0,1 mg/l-0,44 mg/l), 2015 (<0,02 mg/l- 0,11 mg/l), 2016 ( 0,05 mg/l − 0,08 mg/l), 2017 (<0,02 mg/l-0,07 mg/l), 2018 (0,03 mg/l-0,06 mg/l). Average chlorine concentrations exceeded Quality Standards according to the Law of No. 82/200101 (Chlorine 0,03 mg/l). The high concentration of chlorine in the Panasen River water bodies is partly due to the application of KCI fertilizers, pesticides to rice fields, horticultural lands, and domestic waste. (paper)