<p>The present research work aims to document the changes in channel planform and morphology consequent to the commissioning of Mukutmanipur dam on the Kangsabati river in 1974 using a temporal database consisting of district maps, topographical sheets of the Survey of India, and landsat images for the period 1921–2018. The data sets have been analyzed using various GIS techniques, mapping, and field investigation. For assessing the changes, the stretch of the channel under investigation has been divided into three reaches and 24 segments. The results highlight the significant impact of the dam on each and every parameter of the study. The entire channel sinuosity index (SI) increased to 1.80 in the post-dam year (1988) from 1.72 in the pre-dam year (1921). Similarly, the braiding index (BI) value and <i>B-W</i> ratio of the entire channel increased to 1.75 and 2.35 in the post-dam years 1988 and 1978, respectively. So, the impact is noted immediately after the commissioning of the dam, particularly in the alluvial tract of the river, while bedrock tracts of the river remain unaffected. No significant changes in the selected planform parameters are noted thereafter. Hence, the downstream impact of the dam is seemingly short-lived. The study area is located in a densely populated area of west Bengal, where the marginalized people are dependent on various river-based economic activities. Therefore, a thorough study of the regional regime of river dynamic processes becomes essential. From this perspective, such a study is highly significant.</p>