Performance Effectiveness of Communal Wastewater Treatment Plant as an Effort to Control Pollution of the Gajah Wong River, Yogyakarta

Abstract The Gajah Wong River receives wastewater from the high population of Sleman Regency, including agricultural activities and home industries that contain organic pollutants. High pollutants cause dissolved oxygen depletion in waters can threaten lives various aquatic biota. construction a communal treatment plant (WWTP) for handling domestic is an effort to control river pollution. effectiveness WWTP performance based on key parameters continuously monitored, which purpose this research. Surveys 4 (four) WWTPs (Ngudi Mulyo, Wahana Bina Lingkungan, Tirto Mili, Karya Asri Ambarukmo) were conducted February – April 2021 with observed pH, BOD 5 , COD, NH 3 . Sampling by grab sampling at each inlet outlet using ABR (Anaerobic Baffled Reactor) RBC (Rotating Biological Contactor) technology 6 times. results provide overview quality characteristics has been treated (outlet) Ngundi Mulyo (NH 16.55 mg/L, 32.53 COD 213.52 pH 5) Lingkungan 29.85 262.36 6-7), 20.42 66.67 248.7 6-7) Ambarukmo 21.60 252.64 6-7). These reveal four still low not effective reducing NH3 parameters, except BOD5 reaches required standard, processed potential reduce water River. This result also signal managers improve processing process these WWTPs.