C Ciliwung River with total length ±117 km is one of the most important rivers inWest Java. The second segment of Ciliwung River which is across the Kabupaten and KotaBogor has the length of watershed reaches approximately 16 km from the Sindang Rasa District to the Cibuluh District. Along that segment, there are various domestic and nondomestic activities as a potential source of contaminants. The main indicators of riverpollution which deals with the oxygen domestic conditions of the river are Biochemical Oxygen Demand (BOD) and Dissolved Oxygen (DO). A dynamic system model was constructed using the POWERSIM software, and used to describe the tendency of river waterquality fluctuation at certain parts. The population data and sanitation coverage was used to estimate for the analysis of point source pollution in terms of BOD and DO concentration.Verification calculations toward secondary data show that error percentages of the simulationresults of river water quality using this model are 22.44% for BOD and 9.21% for DO. There are data updates through calibrations and validation error percentages results are 27,89% forBOD and 21,99% for DO. Through modification, the model accuracy improved and the error percentages of the simulation results are 7.81% for BOD and 3.71% for DO. Further it has been compared to the scenario if implemented involves 100% sanitation servicepercentage for all domestic wastewater sources. In the second scenario, there is a communal wastewater treatment plant covering all the domestic wastewater from the first part to the sixth part of the river with average sanitation service percentage of 93,14% and 85% BODremoval efficiency. Even though both scenarios give similar results, the second scenario shows a more stable result with relatively smaller BOD concentration compared with the first scenario.