Summary:

The authors performed an estimation of the dynamic of the river bed changes caused by sedimentation and erosion processes. The physical and rheological parameters for chosen cohesive and semi-cohesive sediments were investigated. Mud samples were taken from 3 different localisation on Middle Odra (Poland) and from 2 localisations on Warnow river (Germany). Rheological characteristics were studied with use of the rotative viscometer. Erosion characteristics of the mud’s were studied accordingly to methodology of Migniot [1968]. Results for Middle Odra were verified in the natural scale during the passage of the catastrophic flood through barrage Brzeg Dolny in 1997. This flood caused partly erosion of mud’s from the upstream part of this barrage.