Stream bank erosion is a major source of sediment and nutrients to water bodies. High sediment and nutrient concentrations can degrade aquatic ecosystems and cause eutrophication. For decades major conservation efforts have been made to reduce stream bank erosion, not always successfully. The key for the successful mitigation of stream bank erosion is identifying the areas that are the most prone to such a type of erosion. The implementation of targeted approaches for stream bank conservation practices can reduce efficiently and cost-effectively sediment and nutrient from reaching the water bodies. The purpose of this study was to showcase, with the use of GIS, the areas more prone to stream bank erosion for two sub-watersheds. The two sub-watersheds belong to Axios River transboundary Basin that ends in the Thermaic Gulf of Northern Greece. Specifically, the different reaches of the streams of the two watersheds were separated in different categorizes based on how prone they were to stream bank erosion. The categorization was done within GIS, and the eight parameters utilized were: a) erosive rainfall, b) geology, c) stream

bank slope, d) meandering index, e) stream channel slope, f) watershed erosion coefficient, g) watershed vegetation cover and f) anthropogenic factors. The stream bank erosion categories for the reaches based on the above parameters were: a) no erosion, b) very low erosion, c) low erosion, d) moderate erosion, e) high erosion and f) very high erosion. Once the maps were developed in GIS, they showcased the stream bank erosion susceptibility for the different reaches. Several field measurements were afterwards taken in both sub-watersheds to validate these maps. The field measurements indicate that maps were quite accurate in highlighting reaches with high and very high erosion. Overall, this is an easily adopted method that could be utilized to identify areas highly prone to erosion. This could allow the targeted placement of conservation practices on stream bank that contribute most of the sediment and nutrients in a watershed.