Very little went as planned at Omaha on D-Day, June 6 1944. Difficulties in navigation caused the majority of landing craft to miss their targets throughout the day. German defences were unexpectedly strong and inflicted heavy casualties on US troops as they landed. Under heavy fire the US engineers struggled to clear the beach obstacles, causing later landings to bunch around the few channels that had been cleared. Weakened by the casualties taken just to land, the surviving assault troops could not clear the heavily defended exits off the beach, causing delays for later landings. Small penetrations were eventually achieved by groups of survivors making improvised assaults, scaling the bluffs between the most heavily defended points. By the end of the day two
small isolated footholds had been won and which were then exploited over the following days to achieve the original D-Day objectives.
However, once the beachhead had been secured Omaha Beach became the location of one of the two Mulberry harbours. Construction of 'Mulberry A' at Omaha began the day after D-Day with the scuttling of ships to form a breakwater. By D+10 the harbour became operational when the first pier was completed, unloading 78 vehicles in 38 minutes.
Three days later the worst storm to hit Normandy in 40 years began to blow, raging for three days and not abating until the night of June 22. The harbour was so completely wrecked that the decision was taken not to repair it; supplies being subsequently landed directly on the beach until fixed port facilities were captured. In the few days that the harbour was operational 11,000 troops, 2,000 vehicles and 9,000 tons of equipment and supplies were brought ashore. Over the 100 days following D-Day more than 1,000,000 tons of supplies, 100,000 vehicles and 600,000 men were landed, and 93,000 casualties were evacuated via Omaha Beach.