Blocking - the piling up of ice in a river channel during an ice drift that can lead to flooding.

Stuck individual ice floes between bridges, shoals, islets, etc., blocking the way of ice flow and clogging the river bed.

Blocking usually occurs in constrictions and bends of rivers, on shoals and other places where the passage of ice floes is difficult.

Due to blocking, the water level rises, sometimes causing flooding. Usually large blockages are observed in spring on large rivers flowing from south to north.

The water level rise in rivers due to blockage of the living section by slurry is called a choke.

To combat blocking, the following are used: blackening of the ice surface, destruction of the ice cover by icebreakers, ice-cutting machines or by means of explosions, bombardment of the jam by aviation, use of compressed air.