Between 1809 and 1812, Traversay's main tasks were improving shipbuilding and coastal defences in the Baltic Sea. He reorganized the Baltic fleet structure (over 32 000 men), creating the system of permanent regiment-sized units (fleet crews, ) that supplied manpower to ships and ground forces. This system proved itself during the War of 1812 and subsequent campaigns against Napoleon, and survived until the fall of the House of Romanov.