Flood Potential of Polish Rivers

Comparison of the highest precipitation totals shows that they are lower in Poland than in Europe. This can be explained by moderate and transitional to continental climate of Poland and lowland relief of the country which do not enhance precipitation. Higher precipitation can be obtained by the accumulation of the snow and rapid thawing in the spring time. The different reaction of the rivers to precipitation can be measured by the use of flood potential index k proposed by J. Françou. Flood potential index is calculated using long term discharge measurements at hydrological posts located at major rivers of Poland. Highest values of k index represent Odra river mountain tributaries and upper Vistula tributaries. Lowest values of k index are characteristic for the lowland rivers with a high percentage of lakes and bogs in their catchments. It can be observed a change of flood potential index in the longitudinal profile of Odra and Vistula river reflecting their potential for flood hydrograph transformation. Flood potential index can be used in regional plans of flood risk management.