The Raid on Zeebrugge - 23rd April 1918

by Colin McKenzie

The King of the Belgians opens the Zeebrugge Mole in 1908

Zeebrugge

Zeebrugge stands at the end of an eight mile long canal connecting Bruges with the North Sea. The canal was completed in 1908 with a large set of lock gates at the Zeebrugge end, maintaining the water level in the canal at low tide. A smaller shallower canal connects Bruges with the sea at Ostende.

There are no natural harbours on the coastline near Zeebrugge and so to protect the lock gates and the entrance to the canal from the storms of the North Sea,  Belgian engineers built a harbour wall forty feet high and eighty yards wide stretching one and half miles out into the sea in a curving arc. At the time, this harbour wall (or Mole) created the world's largest man made harbour

The U Boat Threat

The reason for the Germans' great interest in Zeebrugge and the Bruges canal was the fierce submarine warfare they were waging against the British Isles. Ocean-going submarines which had been based on the North coast of Germany could now be moved to a new heavily fortified base at Bruges, cutting three hundred miles off their journey to the Atlantic to attack British shipping.

These submarine attacks continued throughout the war and by 1917 allied ships were being sunk at the rate of four hundred a month. Rationing had been imposed on the British people and the cabinet had been advised that England could be starved out of the War unless the submarine menace was brought under control..

The German U-boat pens in Bruges with their heavily re-inforced roofs. These pens lay at the end of the Zeebrugge canal (IWM)

U-boats often saved torpedoes by surfacing to attack un-armed merchant ships (IWM)

The Dover Patrol

The Royal Navy's Dover Patrol, with bases in Dover and Dunkirk was responsible for defending the English Channel against the German navy and preventing their submarines from using it as a route to the Atlantic. Under the command of Admiral Bacon a huge net, with minefields on either side, was strung across the Channel suspended from fishing boats and buoys.

Admiral Bacon and his colleagues were sure no German submarines could get past this barrage. But in early 1917 documents were found on board a captured submarine off the coast of Ireland which revealed that the Germans were still passing through the Straits of Dover, rather than using the much longer route to the Atlantic via Scotland. The Germans had escaped detection by sending their submarines on the surface at night, passing over the top of the barrage and the minefields.

But despite evidence to the contrary Admiral Bacon refused to accept that submarines were evading detection in the Channel. The Admiralty in London were more inclined to agree with his critics, the strongest of whom was Admiral Keyes the newly appointed Director of Naval Planning.

...Port of Zeebrugge

Admiral Keyes ...