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ENVIRONMENTAL CONSIDERATIONS OF LARGE WASTEWATER TREATMENT PLANTS – THE CITY OF NIŠ CASE STUDY

Nowadays, the Republic of Serbia is at the bottom of the scale of European countries in terms of public utility equipment of the respective communal infrastructure particularly within the area of wastewater collection and treatment. The current situation in the area of water resources management in the Republic of Serbia indicates that the basic problems are insufficient construction of sewerage infrastructure in cities, i.e. insufficient coverage with the sewerage network of users connected to either public or private water supply network, followed by an insufficient number of constructed and operative wastewater treatment plants. In this sense, a particular problem is a requirement for relatively large initial investments in wastewater collection and treatment sector. Also, a special difficulty is the low price of delivered and channeled water within the existing system of public utilities, which is insufficient to provide maintenance of the existing water supply and sewage systems, regardless the future development and improvement of the existing system. Currently, only 10% of total produced wastewater quantity is treated in the Republic of Serbia, with different procedures and with uneven and, most often, insufficient purification effects. In addition to wastewater generated by the population (i.e. households connected to the sewer system), the special problem is the inadequate treatment of industrial wastewater. On the other hand, disposition of treated wastewater, disposal of separated sludge from the treatment process, odor and pest control, noise control, working conditions, etc. are significant challenges for the scientists, professionals and operators. Therefore, the aim of this paper is to comprehensively examine all environmental aspects on the example of a large wastewater treatment plant which is to be gained by the city of Niš, in the very near future.