The Clean Upper Upa project is one of a number of projects contributing substantially to an improvement in the quality of the natural environment. It will bring better quality water in the upper sections of the Upa River, as well as a greater degree of protection for subterranean water. 32 sewer lines have been laid under the project with a total length of 29 km, along with modernization of the wastewater treatment plant in Bohuslavice nad Upou. Construction was carried out in cooperation with Metrostav and OHL ZS.