QUAL2K WATER QUALITY MODELLING OF THE CIKAPUNDUNG RIVER FROM SUKARESMI BRIDGE TO SOEKARNO-HATTA STREET FOR DISSOLVED OXYGEN, TOTAL NITROGEN, AND TOTAL PHOSPHORUS

• Main Author: Ramadhan, Farhan
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/79380
• Institution: Institut Teknologi Bandung

This final project studied Cikapundung River segment within the administrative region of Bandung City. Cikapundung River segment of this study receives pollutant load from domestic sources and commercial activities. The objective of this study was to analyse the nutrients: total phosphorus and total nitrogen, in the river as an impact from domestic and commercial activities within the city, and to formulate water quality control scenarios by modelling the water quality parameters with Qual2K (Q2K) software, to reduce the concentrations of total phosphorus (TP), total nitrogen (TN), as well as to increase the dissolved oxygen (DO) concentration in Cikapundung River. The modelling process was done by inputting data to Q2K calibration by trial-and-error, and then validation through NSE, MRE, and R2 methods. The model was subject of three water quality control scenarios: local oxygenation through weir, optimization of pollutant load to fulfil the regulations, and pollutant load reduction to achieve Citarum Harum’s water quality index of 60. Based on the modelling of those three water quality control scenarios, in which the scenario 1 was set as the existing condition, Scenario 2 only succeed in increasing the DO concentration. Scenario 3 requires 99.34% and 99.56% reduction for TP to meet Class II stream standard regulation and US EPA’s recommended TN concentration, followed by an increase of DO to above 5 mg/L across all reaches. Scenario 4 resulted in the requirement of reduction of TP pollutant load to 88.64%. The Q2K model was also used to determine the Total Maximum Daily Load (TMDL) for the Cikapundung River, where TP and TN has TMDL of 1386.38 kg/day and 2296.74 kg/day respectively at low-flow conditions.