Abstract This research was conducted in February 2021 at the mouth of the Dumai River, Rupat Strait. The purpose of this study was to determine the effect of sediment supply from land on changes in bathymetry in the waters of the Rupat Strait based on the analysis of suspended sediment (SSC) and suspended solids (TSS) divided by the area of the study. The method used is a survey method. The re…