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Loads Of Pollutants Discharged To The Batic Sea By The Oder And Vistula Rivers 
During A Flood Wave In July And August 1997. 
Anna Bozek & Waldemar Jarosinski 
Institute of Meteorology and Water Management 
ul. Jordana 10/11 
40-056 Katowice 
Abstract 
Measurements of concentrations of pollutants performed on the routine basis within the 
framework of the Surface Water Monitoring in Poland, together with the measurements of 
flows in the Vistula and Oder rivers enabled assessment of the magnitude of loads of pol 
lutants carried by a flood wave in July and August, 1997. 
Evaluation of loads of pollutants discharged to the Baltic Sea by waters of the flood wave was 
based on measurements done in two bench-mark gauging sections located near the mouths of 
the Oder (in Krajnik) and the Vistula (in Kiezmark) rivers.Flows calculated for these two 
gauging sections for period of flood are presented in graphes below. 
For evaluation of quality of the river water, the following parameters were selected: BOD, 
COD-Cr, chlorides, dissolved solids, suspended matter, calcium, magnesium, nitrate nitro 
gen, total nitrogen, phosphates, total phosphorus, zinc, cadmium, copper, lead and mercury. 
When comparing ranges of concentrations observed during the flood, for the Vistula at 
Kiezmark and for the Oder in Krajnik, with values measured in summer months in the years 
from 1990 to 1996, almost all of the indices during the flood didn’t approach extreme values 
observed since 1990. 
It can be stated that 24 hours loads of certain pollutants carried by water of the Vistula and 
Oder rivers increased markedly in the analysed period, first of all due to a manyfold increase 
in the magnitude of water flow. Maximum increase of daily loads was observed for these pa 
rameters, which achived the maximal values of concentrations during the flood period, in a 
moment when maximum flow was observed. In the Vistula these were: COD-Cr, suspended 
matter, nitrate nitrogen, phosphates, cadmium, copper and mercury. 
For the same reason, in the Oder river, the maximal increase of dayly loads were observed 
for: phosphates, zinc, copper and lead. Loads of pollutants discharged to the Baltic Sea by 
the Oder and Vistula rivers during the flood wave in July and August 1997, compared with 
loads in an analogous period of 1996 are presented in tables 1 and 2.