The thesis deals with the issue of intrusion of extraneous water into the sewage system. Preventing and reducing the possibility of intrusion of extraneous water into the sewage system is an important factor in reducing operating costs of wastewater treatment plants.
In the theoretical part of the thesis, at the beginning, Slovenian and European legislation relating to the collection and treatment of wastewater is presented. Next there is some theory about water protection areas. More information is given on collection and treatment of urban waste water and extraneous water. The final part of the theoretical part describes municipality of Tišina and wastewater treatment plants in Murski Črnci and Petanjci.
In the practical part of the thesis, we calculated the proportion of extraneous water for each pumping station according to the data of the electricity consumed. From the data about sold water quantities it is clear, that the amount of water sold in Tišina is very small compared with the flow at the wastewater treatment plants, so we tried to determine which pumping stations have largest share of intrusion of extraneous water into the sewage system. Because there are 39 pumping stations that pump water towards the wastewater treatment plants, intrusion of extraneous water into the sewage system presents a huge financial burden for the municipality. For pumping stations where we calculated large shares of extraneous waters, we tried to anticipate the causes of the intrusion of extraneous water. In conclusion, the thesis presents possible solutions and measures by which it is possible to identify and reduce the intrusion of extraneous water in the sewage system.