The Duu River is heavily polluted through varied human activity along its course. Despite the potential health hazards that the pollution of water bodies has on aquatic lives and persons who use the water bodies, river pollution persists. Samples from four points Slipway Community, Rock Spring Valley Community, Jallah Town 1 and Jallah Town 2 communities were subjected to both physical and chemical tests. The study identified uncontrollable dumping of wastes, defecation and institutional failures as root causes of pollution of the Duu River. The main anthropogenic causes were identified as indiscriminate dumping of refuse, channelling of raw sewage, defecation, discharge of untreated effluents from clinics and households waste into the Duu River. Physical tests showed that the Duu River was polluted since its turbidity exceeded Liberia Water Quality Standard (LWQS) class II (≤5 mg/l) for surface water. This indicated that Duu River is polluted with chromium wastes or chromium materials which was disposed and has leased into the river. The defecation and dumping of wastes into the river are on the increase among other human activities. On this note, building of toilet houses, providing of garbage cans, sanitizing citizens on how their activities can harm life in the river including themselves, timely collection of wastes and proper enforcement of laws were recommended.