Eutrophication is a global problem that has a major impact on aquatic ecosystems. Over the past 50 years, the nutrient content of lakes and streams has increased as a result of urban development and agricultural sources. It can cause health problems for both humans and animals through direct contact or when consumed. In addition, it can result in the extinction of aquatic organisms. By studying the topography, soil chemistry, hydrology and human impact of areas, we can understand how nutrients are transported from their sources of origin to surface water, where they increase nutrient content. Understanding this is crucial to identify and prioritise areas that require action to reduce the effects of eutrophication. The purpose of this study was to trace potential sources of dispersion of nutrients to the surface water through analysis of these. The site chosen for the study was the area of Tvärålund where the stream Sjöbäcken and lake Tväråträsket are located, where 11 sampling points were also placed. These had the purpose of proving any emissions from ancillary activities. The results indicate that only one of the selected sampling points was contaminated from active point sources (individual sewers) while the remaining points showed a constant increase supported by a linear relationship between distance from the reference point and measured concentration.