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The sewage treatment plant of the Dhaka Metropolitan, known as Pagla Sewage Treatment Plant (PSTP) was designed to treat a maximum flow of 120,000 m3 /day of domestic sewage generated from about 18 per cent population of the metropolitan. The final effluent from the treatment plant is discharged into the adjacent Buriganga River. The treatment process in application is basically a low cost option consisting of grit chamber, primary sedimentation tank, facultative lagoon, chlorination system and sludge lagoon (Figure 1). There has always been a general complaint of shortcomings of the overall performance of the plant, which is in fact evident from an obnoxious and foul smell even at the fag end of the plant. In quest of optimisation of treatment process; a study was undertaken where both qualitative and quantitative aspects of sewage with particular emphasis on the characteristics of influent, effluent and sludge were checked and determined with laboratory aids. The hourly as well as seasonal variations of various parameters were also studied. This paper highlights some significant aspects of the study and aims at drawing conclusions in order to facilitate optimising the sewage treatment operation of the plant.