Flash floods caused by heavy downpours can result in economic damages (local floods). Prediction of such events relies mainly on weather forecast. As predictions of the time and place of heavy rains are not adequately precise, forecasting of fl ash
floods in small basins encounters serious limitations. Prediction of fl ash floods in small basins may be supported by delineation of basins prone to fl ash floods. The article presents results of investigation attempting to delineate such basins
The article presents spatial distribution of water fl ow velocity in Vistula River bed. The study area covers the Vistula River reaching from km 533.000 to 542.000, i.e. between Warsaw and Modlin. The aim was to establish spatial distribution