Livanjsko Field in Bosnia and Herzegovina is the largest karst field in the world. It is on the list of Wetlands of International Importance, protected under the Ramsar Convention (The List of Wetlands…, 2013). The river Cetina which runs through the field is downstream used for drinking
water preparation. In the Livno Field there is a settlement Grborezi with approximately 1000 residents and no sewage treatment. The settlement has new sewage system, ending in a small concrete septic tank of 5 m3 in volume for primary treatment, with outlet into surface water Cetino.
Constructing the wastewater treatment system at this location is of key importance for conservation of protected environment Livno Polje as well as downflow drinking water quality. Professional study of this case was made by international organizations, all of them concluding that constructed wetlands are the most appropriate technology (Gotovac in sod., 2008). Based on the study (Gotovac in sod., 2008) and an existing outline scheme number 48/09 (Ameršek, 2010), we made a detailed design of constructed wetland. The proposed system consists of mechanical pretreatment and seven reed beds with subsurface flow. The combination of vertical and horizontal flow treatment wetland was used to achieve optimal efficiency. Anti-flood measures were also considered.
The thesis consists of technological and technical descriptions of treatment components, detailed design, list of materials and cost estimate. This kind of wastewater treatment would be the optimal solution to Grborezi sewage treatment problem as it takes environment protection, drinking water conserving and financial perspective into account.