Riverbank erosion has been a serious concern in Assam since a long time as the mighty river Brahmaputra flows through the state at a stretch of 720 km. Matmara, Dhakuakhana sub-division of Lakhimpur district, Assam has been one of the places that has faced the brunt of severe erosion in the past years. Therefore, this study has been taken up with the aim to analyze the effectiveness of the geotubes that were installed in Matmara for erosion and flood control. A 5 km long structure for protection was constructed using sand-filled geotextile tubes (geotubes), arranged in a one-over-two formations, with each tube measuring 40 m in length. The objective of the study was to measure the shift of the bankline from the year 1990 to 2023. The study was carried out over a course of 33 years with 10-year intervals, viz., 1990, 2000, 2010, 2020, and 2023. LANDSAT imageries from USGS Earth Explorer were downloaded for the study. The ArcGIS version 10.8.2 was used for the analysis. This study revealed that after the installation of geotube dykes, the bankline started shifting to the right side of the bank from the year 2020, whereas before the protection measure, the bankline in the years 1990, 2000, and 2010 was shifting to the left side, indicating severe erosion of the bank. Soil tests were also conducted in that area to check the availability and fertility of the soil where geotubes were installed. pH was found to be in alkaline range, whereas other parameters, such as the NPK content and OC and EC of the soil, were found to be very low in range. Residents who had experienced the severe flood of 2000 have been living comfortably in their shelters for the past 12 years, free from the threat of further flood and bank erosion.