The biological structure of the Upper Vistula basin consists mainly in natural plant communities. Generally they properly protect stream beds. Studies of the natural communities enable identification of the plant species which, together with technical structures, contribute to regulating and reinforcing banks against the destructive effect of flowing water. Based on phytosociological studies on the biological cover of bed banks in the Soła, Skawa and Dunajec basins, the author shows that grass, shrubs and trees can play a vital role.