Original sentence: As commander of the Marinestation der Nordsee, he was oversaw the building (1905-08) of a heavy gun fortress installation at Cuxhaven at the mouth of the Elbe River to protect the Elbe estuary, Hamburg and the North-Baltic Sea Canal (Kiel Canal from enemy raids from the North Sea.In 1900 and 1902 he was senior admiral at Wilhelmshaven
Edited sentence: As commander of the Marinestation der Nordsee, he oversaw the building (1905-08) of a heavy gun fortress installation at Cuxhaven at the mouth of the Elbe River to protect the Elbe estuary, Hamburg and the North-Baltic Sea Canal (Kiel Canal from enemy raids from the North Sea.In 1900 and 1902 he was senior admiral (commander) at the North Sea Naval Station (Marinestation der Nordsee) at Wilhelmshaven