Changes of water pollution dynamics in Vistula river on Warsaw city area

The paper presents change of water quality within Vistula River in the city of Warsaw. Water samples for analysis were taken from four different measurement points in the period from February to June 2016. Based on the results of laboratory studies it was demonstrated that the Vistula River in Warsaw is exposed to the input of pollutants contributing to increase the salinity, especially in winter and early spring. The concentration of both chlorides and sulphates were highest in February and was decreasing in subsequent months of the year. At the same time it has been shown that during the entire study period the concentration of Cl– ion exceeded the limit values for water quality II class in Poland. While the SO4 2– concentrations in water samples taken in the winter months (February-March) exceeded the limit values for the second quality class, in April, it was within the acceptable range for II class water quality, and in May and June does not exceed the value referred to as standard for I class of water quality. Based on the analysis of indicators of nutrients (N-NH4 , N-NO3 , Ptot.) it was found that the Vistula is not exposed to eutrophication due to their low concentration, which indicates a very good water quality. At the same time permanganate index (CODMn) indicates a low organic load of Vistula.