Specific features of wastewater formation and inflow into municipal sewerage systems in Belarus

   The paper examines the conditions of wastewater formation entering the municipal sewerage system, categorized by main sources of inflow: domestic wastewater from the population, wastewater from enterprises and organizations, and additional inflow (infiltration). The structure and formation conditions of various wastewater categories are analyzed in detail, along with factors and specific features of their entry into sewer networks. Additional water inflow into this system is classified as organized and unorganized. Based on data from the 1-voda statistical report (Ministry of Natural Resources) “Report on Water Use” for the period 2020–2024, an assessment was made of the volume of additional water inflow into the municipal sewerage system and its impact on the efficiency of municipal wastewater treatment facilities. It was found that the volume of additional water inflow in the analyzed populated areas ranges from 0.82 to 49.66 %. At the same time, when broken down by populated area by population equivalent, the average share of the annual volume of additional inflow by group varies between 20.97 and 24.54 %, which is a fairly large value and indicates a significant share of additional water entering the sewerage system of the populated area and wastewater treatment facilities. The factor analysis did not reveal a direct functional relationship between the amount of additional water inflow and the equivalent capacity of treatment facilities, as well as the annual volume of precipitation, which indicates that the volume of additional water inflow is dominated by organized additional inflow, caused by the imperfection of the accounting system for certain categories of wastewater entering the municipal sewerage system.

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