Changes in the Quality of Domestic Sewage Caused by the Reduction of Water Consumption in Households

Since the 1990s, there have been trends in Central and Eastern European countries to reduce water consumption. This phenomenon is closely related to the political, social and economic changes in these countries and the introduction of economic instruments in water management. The article presents the changes in water consumption in households in the years 1950–2019 depending on the degree of equipping buildings with sanitary facilities, and the structure of water consumption for particular purposes. For the same period, the quality of sewage generated in households is presented on the basis of bibliography. The content of total suspended solids was the main analysed parameter. The last part of the article presents the quality of wastewater discharged to fourteen Polish wastewater treatment plants. The majority of the analysed plants show an increase in the concentration of total suspended solids in the domestic sewage discharged to them. This phenomenon may be influenced by the decreasing water consumption in households.