Robert Lochner (engineer) harbours to Franklin Roosevelt and Winston Churchill. The decision to go ahead was taken and full-scale trials of the floating breakwater started in April 1944. During the trial, an onshore gale produced heavy seas, but Robert's bombardons calmed the waves effectively. Assembling two Mulberry Harbours the day after the landings on 7 June 1944 was one of the most remarkable engineering feats in history. A total of 1,500,000 tons of harbour equipment had to be taken across the channel in an operation involving 150 Allied tugs, and by D-Day 'plus 12', most of Lochner's concrete breakwaters were in position. On
Mulberry harbour Dundas & Whitson, Mowlem, Nuttall, Parkinson, Pauling & Co. and Taylor Woodrow. On completion they were towed across the English Channel by tugs to the Normandy coast at only 4.3 Knots (8 km/h or 5 mph), assembled, operated and maintained by the Corps of Royal Engineers, under the guidance of Reginald D. Gwyther, who was appointed CBE for his efforts. Both locations for the temporary harbours required detailed information concerning geology, hydrography and sea conditions. To collect this data a special team of hydrographers was created in October 1943. The 712th Survey Flotilla, operated from naval base HMS "Tormentor" in