In September 2020, two major fires broke out in a large crude oil tanker in Sri Lanka’s maritime zones. An island with a vast sea area in the Indian Ocean, Sri Lanka, is prone to vessel sourced pollution. Crude oil can have a damaging impact on the environment, and therefore tracking the spill in the water is essential. Spaceborne sensors support monitoring oil pollution; however, optical sensors need clear skies for observation. The detection of pollution caused by vessels; in Sri Lanka’s maritime zones has previously been investigated by the author. This study examines the data collected by the Sentinel-1 satellite, whose sensing corresponds to the oil spill event, manually and using algorithms to detect the presence of oil spills. Two detected oil spill areas were measured to be 0.6 km and 1.4 km long. Further, in this study, the SAR sensor’s vertical signal transmission and reception mode produced acceptable results in detecting the spills and the vessel. Sentinel-1 SAR data is essential, in this case, to detect the presence of the oil spills and the vessels.