Water quality characterized as a measure of the physical, synthetic, organic, and microbiological characteristics of water. Water quality monitoring and measurement give an experiential proof to support decision making on issues related to health and environmental impact. Maritime operations are one of the factors that contributed to the environmental impact, particularly on the water quality status. The interactions of Lumut water (Dinding River) with several maritime operations nearby can lead to marine pollution and bring negative effect to the natural habitation. Through preliminary observations, oil spillage and garbage were discovered at the surface water of Dinding River. This study is conducted to identify the current status of water quality at Dinding River. Water samples from 5 fixed stations along the river were collected regularly and analyzed to determine the status of water quality based on the chosen water parameters - Conductivity, Total Suspended Solids, pH, Total Dissolved Solids and Dissolved Oxygen. Pollution Index is used as a tool to determine the status of water quality at the research area. The results show that the water at Dinding River is moderately polluted.