Initially subordinate to the Referee of the Riverine Fleet in the Ministry of Military Affairs in Warsaw, in 1932 it was separated as a semi-independent branch of the navy based in Pińsk.
Other members of the staff were: On September 15, 1939, the Riverine Flotilla received orders from the commanding officer of the Independent Operational Group Polesie, Gen. Franciszek Kleeberg.
Because of a possible breakthrough of the German forces in the northern sector of the front, the orders for the Flotilla were to prepare a defence of a 200 kilometres long front along the Prypeć river.
However, a particularly dry and sunny summer resulted in shallow waters preventing many ships from reaching their area of operations.
In addition, the Soviet invasion of September 17, 1939, made the plans obsolete.