THE VISTULA RIVER LOW FLOWS IN WARSAW IN THE 21ST CENTURY

Abstract

The aim of the paper is an analysis of low flows – a phenomenon of persistent low water levels and flows in the riverbed – of the Vistula River at the Warszawa-Nadwilanówka gauging station. The study concerned the beginning of the 21st century, against the 1951–2000 period. In order to determine the low flows on the daily flows hydrographs, they were cut-off by the threshold level method. According to the adopted criterion, low flows are rather rare on the Vistula in Warsaw. The longest and most severe drought in terms of outflow deficit occurred in 1951. In the last years of the studied period (2003, 2012, 2015), droughts have reached a considerable sizes, but were no greater than the low flow observed in 1951. Since 1985 no winter low flows have been recorded.