Introduction Water is a universal symbol of life. The reality of water resources in Bangladesh, however, is a cause for grave con- cern. Both the quantity and the quality of surface and ground water supplies are already uneven, and the incidence of pol- lution and of scarcity is on the rise. Water is essential for all living beings, and man is no exemption. So most of the human civilization has developed on the banks of rivers, lakes or seas. Today, nearly 40 percent of the world's food supply is grown under irrigation, and a wide variety of indus- trial processes depends on water (BCAS, 2000). Bangladesh is a land of rivers. Around 230 rivers flow through the coun- try including 53 international rivers. Urbanization is the main reason of pollution for these rivers and other water bod- ies (DoE, 2001). Several studies (DoE, 1993; Hossain, 2001) showed that surface water quality of the rivers of the coun- try is highly polluting day by day. River Karnafully is the largest and an important river in Chittagong and the Chittagong Hill Tracts, originating from South Lushai Hills, a lofty range of Hills of Assam in India at Latitude 23 o 53 / N and Longitude 92 o 27 / E. The Karnafully river enters into region Chittagong in the west and south?west directions and finally falls after a course of 180 km, into the Bay of Bengal in 22 o 14 / N and 91 o 47 / E at Patenga, leaving the city of Chittagong on its right bank, about 16 km away from the out- let. Before that, it travels through mountainous wilderness making a narrow loop at Rangamati and then follows a zigzag course forming two other prominent loops, the Dhuliachhari and the Kaptai. The hydroelectric dam is situ- ated just before the entrance of the river into the Kaptai loop. River Karnafully that facilitated the initiation with escalation of the dwelling places as well as industrialization along its shores. During its flow it promotes industrial, agriculture, fishing, household and navigational infrastructure. It is now faced with terrible deterioration of natural water characteris- tics (Hossain and Khan, 2002). In Chittagong the Karnafully made most significant change in its course from Kalurghat downwards. The change has been taking place for more than a century. Formerly, the river had a western and southwest- ern course from Kalurghat followed by Sampanghata, Suloop Bahar, Kapashgola, Chowk Bazar, Roomghata, Ghat Water Quality Parameters: A Case Study of Karnafully River Chittagong, Bangladesh M. Iqbal Sarwar,* a Ahmad Kamruzzaman Majumder b and M. Nurul Islam c a Department of Geography and Environmental Studies, University of Chittagong, Bangladesh, b Department of Environmental Science and Engineering, Kathmandu University, P.O. Box 6250, Kathmandu, Nepal, c Department of Geography & Environment, Jahangirnagar University, Savar, Bangladesh Abstract The river Karnafully is one of the Himalayan River originating from the Lushai Hills in India. The catchments of the Karnafully and its allied streams cover 5,500 (14,000 sq km) square miles. Water samples were collected from Karnafully River along different points and ana- lyzed for various physiochemical parameters during winter. Effects of industrial wastes, municipality sewage and agricultural runoff on the river water were investigated. The study was conducted between the Kaloorghat Bridge and Patenga estuary including Chittagong port. This is the most polluted area due to the presence of many chemical fertilizers, iron, leather and pharmaceutical industries. All these industries discharge their untreated toxic waste water directly into the river Karnafully. The study involved determination of physical and chemical parameters of surface water at different points. The mean values of water temperature, total suspended solids (TSS), total dissolved solids (TDS), total solids (TS), turbidity, dissolved oxygen (DO), bio-chemical oxygen demand (BOD), chemical oxygen demand (COD), pH, elec- tric conductivity and total alkalinity were 23 o C, 365.87 mg/L, 8018.8, 8518.33 mg/L, 31.54 FTU, 1.55 mg/L, 6.65 mg/L, 13961 μs/cm, 247.47 mg/L, 560.27 mg/L and 4.8 mg/L respectively. Key words: Physiochemical parameters, Winter season, Monsoon season, Dissolved oxygen, Biological oxygen demand. Bangladesh J. Sci. Ind. Res. 45(2), 177-181, 2010 Short Communication BCSIR Available online at www.banglajol.info BANGLADESH JOURNAL OF SCIENTIFIC AND INDUSTRIAL RESEARCH E-mail: bjsir07@gmail.com * Corresponding author: E-mail: iqbalsrwr@yahoo.com