Flood defense embankments are hydraulic engineering structures that have a permanent or occasional function of protecting the protected area from floods. As with all engineering structures the designer must know and understand the physical - mechanical properties of the foundation soil and construction materials, and how the foundation soil and embankment structure will react under load, either during construction or in the use phase under normal and extreme operating conditions. In order to define the soil parameters with which the analysis of the embankment construction will be carried out, it is necessary to carry out quality geomechanical research works and laboratory tests. Geotechnical investigation works consist of field research works and laboratory tests. The analysis of the obtained results of field and laboratory tests determines the parameters of the soil material at the location of the site and along the location of the embankment. Geostatic calculations prove that the building structure during its construction and use will meet the basic requirement of mechanical resistance and stability in the part in which the soil, rock and groundwater affect the building structure. Calculations in the Republic of Croatia are carried out according to the Croatian standards Eurocode 7 and Eurocode 8:  standard HRN EN 1997-1: 2012 and HRN EN 1997-1: 2012 / NA: 2012  standard HRN EN 1998-5: 2011 and HRN EN 1998-5: 2011 / NA: 2011. If geostatic calculations do not prove the stability with the proposed embankment geometry, layers of the foundation soil and materials from the excavation site, one of the geotechnical solutions is to improve the properties of the soil and embankment layers with geosynthetics. All necessary calculations for the needs of embankment sizing were performed in the GEOSTUDIO 2016 program (GEO-SLOPE International Ltd., Calgary, Alberta, Canada).