THE ANALYSIS OF VARIABILITY IN WATER QUALITY IN THE BIALA TARNOWSKA RIVER

The paper presents the results of hydrochemical tests of Biała Tarnowska River, right-bank tributary of Dunajec. Water catchment area of 983.3 km2 has a submontane character and it is located in Małopolska Province. 64% of the area is used as arable land, the rest is forest land and urbanized and built-up areas. Downstream, in the area close to the city of Tarnów, industrial areas prevail (chemical industry). The testes were carried out from 2010 to 2012 in three measuring-control points located along the 82 km river section. 32 physicochemical indicators, obtained from the Voivodeship Inspectorate of Environmental Protection in Kraków with a local branch in Tarnów, were analysed in the paper. Based on the obtained results it was stated that the water potential in the middle and upper course of the river (1st and 2nd point) was below good and in the lower course (3rd point) it was good. The chemical status of the tested surface water in these points was good. Because of high concentrations of total suspended solids in each point, the river water cannot be used in water supply for human consumption. Exceeded concentration of total suspended solids, among other things, is the reason why river water does not fulfil the natural conditions of habitat of the salmonid and carp family fish. Out of 15 tested water physicochemical indicators, 14 were statistically higher in the lower part of the catchment area. Greater water pollution in the middle and lower course of the river is caused by anthropogenic pressure.