Rapid population growth in Bangladesh has led to an increase in the rate of urbanization across the country. Runoff is increased due to an increase in impervious surfaces as a result of urbanization. Sylhet City Corporation (SCC) is a metropolitan city in northeastern Bangladesh that is frequently afflicted by urban flooding and waterlogging as a result of storm runoff due to heavy rainfall. A substantial portion of the city suffers from severe drainage congestion, which is caused by the inadequate drainage system, lack of maintenance of drainage system, garbage dumping in the drains and canals, and illegal encroachment of drainage canals. The review of the existing drainage system and the causes of the drainage congestion in the city area have been assessed in this study. This study also focuses on the stormwater management of Goali chhara sub-system of eastern part of Sylhet City Corporation which is responsible for waterlogging in the study area. The Goali chhara sub-system has been modeled using GeoSWMM to analyze the stormwater runoff and to prepare a masterplan of drainage network considering the climate change issues. The design water level of the Surma river has been estimated from historical river water level data using the Gumbel distribution method. Moreover, analyzing the historical rainfall data of Sylhet Station, the IDF curve for short-duration rainfall has been developed and the design rainfall intensity of 2-hour and 5-year return period has been estimated. These hydrological parameters have been used in the model and prepare the drainage network masterplan. The model has been calibrated using the estimated runoff coefficients from the land use map for the sub-catchments. The stream cross-sections for the 10-year return period were found to be larger than that obtained for the 5-year return period. This research will help the local authorities of Sylhet City Corporation by allowing them to make drainage capacity expansion decisions that will tackle this critical challenge for the next 30-40 years.