Mulberry Harbour Port Winston, what was it and what remains now..

Chris Howlett Howlett Hydrographic Services Mulberry Harbour

Mulberry Harbours

What were the Harbours?

What is left today?

The Survey

What were the harbours?

• As early as 1941, while most were thinking of repelling a German invasion of Britain, a small group were exploring how Britain could re enter Europe to beat the occupying German force and liberate the occupied countries.

• An Army unit named Transportaon 5 or Tn5 was formed to invesgate means of rapidly pung ports back into operaon should the enemy destroy them before retreang. What were the harbours?

• Tn5 developed portable cranes, dredging machines and even prefabricated lock gates. They also built two new military ports in UK to receive stores from America. Military Port 1 was at Faslane while Military Port 2 was at Cairn Ryan.

• In 1942 their remit was enlarged to develop pierheads and bridges which could be deployed on open beaches and allow ships to discharge stores. What were the harbours?

• In August 1942 the ill fated Commando raid against the French channel port of Dieppe in which the aackers lost some 3,000 troops as either dead or captured while the defenders hardly noced proved the implausibility of capturing a French port by frontal assault.

• Eventually the audacious plan of building a port from pre-fabricated components, towing these over the channel and then building it on the far shore took hold. What were the harbours?

• Two harbours were ordered, each larger than the port of Dover and able to be put together in a maer of days. One harbour was for the Americans at and called Mulberry A while the second was for the Brish and Canadians at and called Mulberry B.

Construction

• 23 pier-heads

• 10 miles of road bridge comprising 660 80 foot spans • 670 floats to support the road bridge (470 concrete, 200 steel) • 8 shore ramps • 50 Bombardon floating breakwaters • 213 Concrete Phoenix caissons

Construction consumed over 210,000 tons of steel and 1,000,000 tons of concrete.

To maximise available building sites and workers, construction was spread throughout Britain. Construction

Construction

What were the components?

Gooseberries

Gooseberry 1 – Utah

Gooseberry 2 – Omaha Mulberry A Gooseberry 4 – Juno

Gooseberry 3 – Gold Mulberry B Gooseberry 5 – Sword Gooseberries

Corncobs

Blockships prepared in Scotland by cutting holes in internal bulkheads and placing charges below the water line then sailed to France to form instant breakwaters called Gooseberries.

Each landing beach had a gooseberry made of about 12 corncobs each.

Bombardons

Floating breakwaters moored seaward of main breakwaters to provide sheltered deep water anchorages. Original design was for a 200 foot long flexible air filled rubber tube with a 200 ton concrete keel nicknamed ‘Lilo’.

Production model was made of steel since it was felt that the rubber would damage too easily.

Bombardons

Mulberry B taken about June 9.

Gooseberry 3 is complete as are the Bombardons (indicated by red oval).

Whale roadways are advancing from the beach.

Gooseberry 4 at Courseulies-sur- Mer is also complete in the distance. Aerial photo of the US operated Mulberry A taken around June 15. The bombardons are at the top.

Phoenix

Phoenix

Concrete caissons sunk end to end to form a continuous . What were they?

Whale

Whale

Floating roadways and movable pier heads to allow ships to unload at all states of the tidal range. What were they?

Building What were they? In Use

Storm!

What is left today?

After the harbour was abandoned the bridges were removed with many being used to repair those destroyed throughout France. Beetles and Phoenix were also used to plug gaps in various dykes in Holland. Other steel items such as the Corncobs were largely salvage in the 1950s and 60s. The last movement of Phoenix units happened in 1953 after the great storm when several were towed to Holland and used to repair the breached sea defences.

Surveying