There were also plans to break the dams on the Biebrza and Narew rivers to flood the area, but the summer of 1939 was one of the driest seasons in Polish history and the water level was too low.
Postojao je i plan o rušenju brana kod rijeke Biebrze i Narve da bi se ta područja potopila, no ljeto 1939. bilo je jedno od najsušnijih u povijest Poljske pa je to bilo nemoguće.