In the Saale river catchment (DE) as well as in in the catchments of river Vltava and river Ohře (CZ) several dams and retention areas exist, that played an important role for reducing the flood peaks during the past flood events. The German Federal Institute for Hydrology analysed in cooperation with the Masaryk Water Research Institute and AquaLogic Consulting the effect of Czech (on river Vltava and Ohře) and Thuringian retention measures on extreme flood events at the Elbe.

The analyses show that during the flood 2011 the measures at Vltava and Ohře as well as the control of dams at the Saale caused reduced flood water levels all along the German Elbe. The average reductions are between 1.04 m at the gauge Usti nad Labem and 33 cm at the gauge Wittenberg. Hence, it could be significantly contributed to the reduction of flood risks.

The results also show: All measures that have a positive impact on the Czech Elbe catchment are also beneficial for the German catchment area: Even at the gauge Neu-Darchau (about 540 km below the Czech-German border) the flood 2011 was reduced from a 50-yearly event to a 25-yearly event.

Summary for 2011 (german only):

Calculation for 2002 and 2006 (german only):

Summary of all calculations (german only):

Responsible Partners: German Federal Institute for Hydrology, BfG, DE; Masaryk Water Research Institute, VUV, CZ; AquaLogic Consulting, CZ; Thuringian ministry for agriculture, forestry, environment and nature protection, TMLFUN, DE