Mulberry Harbour. Port Winston, what was it and what remains now.. Chris Howlett Howlett Hydrographic Services

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1 Mulberry Harbour Port Winston, what was it and what remains now.. Chris Howlett Howlett Hydrographic Services

2 Mulberry Harbours Mulberry Harbour What were the Harbours? What is left today? The Survey

3 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 TransportaEon 5 or Tn5 was formed to invesegate means of rapidly pugng ports back into operaeon should the enemy destroy them before retreaeng.

4 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.

5 What were the harbours? In August 1942 the ill fated Commando raid against the French channel port of Dieppe in which the arackers lost some 3,000 troops as either dead or captured while the defenders hardly noeced 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.

6 What were the harbours? Two harbours were ordered, each larger than the port of Dover and able to be put together in a marer of days. One harbour was for the Americans at Omaha beach and called Mulberry A while the second was for the BriEsh and Canadians at Gold beach and called Mulberry B.

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8 Construction 23 pier-heads 10 miles of road bridge comprising 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.

9 Construction

10 Construction

11 What were the components?

12 Gooseberries Gooseberry 1 Utah Gooseberry 2 Omaha Mulberry A Gooseberry 4 Juno Gooseberry 3 Gold Mulberry B Gooseberry 5 Sword

13 Gooseberries Corncobs Blockships prepared in Scotland by cutting holes in internal bulkheads and placing scuttling 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.

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17 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.

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21 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.

22 Aerial photo of the US operated Mulberry A taken around June 15. The bombardons are at the top.

23 Phoenix

24 Concrete caissons sunk end to end to form a continuous breakwater. Phoenix

25 What were they?

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31 Whale

32 Floating roadways and movable pier heads to allow ships to unload at all states of the tidal range. Whale

33 What were they?

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35 Building

36 What were they? In Use

37 Storm!

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39 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.

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42 Surveying

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