Compiled by Lara Godbille, Director, U.S. Navy Seabee Museum, Naval History and Heritage Command
June 6, 1944
During World War II, nearly 325,000 men served as U.S. Navy Seabees. Although the majority of them deployed to the Pacific theater, many Seabees also served in the Atlantic theater. In particular, the Seabee played a vital role in the invasion of Normandy. During D-Day of the Normandy invasion on June 6, 1944, the Seabees were among the first to go ashore as part of Naval Combat Demolition units. Working with U.S. Army Engineers, their crucial task was to destroy the steel and concrete barriers that the Germans had built in the water and on the beaches to forestall any amphibious landings. When sunrise revealed their presence, they came under brutal German fire. Entire teams were wiped out when shells prematurely detonated their explosives. Despite the danger, the survivors continued to work until all their explosive charges were planted. As a result of their heroic actions, the charges went off on schedule and huge holes were blown in the enemy’s defenses.
The arduous assignment of the combat demolition units was only the beginning of the Seabees’ work on Normandy’s beaches. After the invasion fleet had arrived off the coast, approximately 10,000 Seabees of Naval Construction Regiment 25 (25th NCR) began manhandling their pontoon causeways onto the beach. It was over these causeways that the infantry charged ashore. Under constant German fire, directed at slowing or stopping the landings, the Seabees succeeded in placing large numbers of these pontoon causeways. Allied troops and tanks subsequently swept ashore in ever greater numbers and pushed the German defenders inland.
The Seabee contribution to the success of the invasion was not restricted to assembling and placing pontoon causeways. They also manned the large ferries known as Rhinos that carried men and supplies from the larger ships to the beaches. These ferries were actually little more than floating pontoon structures powered by giant outboard motors. Huge amounts of much needed equipment were hauled ashore on Rhinos during the first few days of the invasion.
The Seabees also built offshore cargo and docking facilities, piers, and breakwaters. These were constructed out of old cargo ships, special prefabricated concrete structures that were floated over from England, and the ubiquitous steel pontoons. The huge port area that was formed out of this odd combination of materials became known as Mulberry A. Even after the artificial harbor was partially destroyed in a severe storm, the Seabees landed hundreds of thousands of tons of war material daily. In addition to these massive amounts of supplies, by July 4, only 28 days after D-day, the Seabees had helped land more than a million Allied fighting men on the shore.
During the war, the Bureau of Yards and Docks (the predecessor to NAVFAC), published a biweekly periodical called the Seabee News Service which gathered and disseminated information about what the Seabees were doing during the war; in many ways it was the World War II era equivalent to Seabee Online. Unlike official reports, the stories printed in the Seabee News Service revealed a more human side of the war. Below are two articles that reveal more about the Seabees involvement during the invasion of Normandy excerpted from the Seabee News Service.
Civil Engineer Corps officers with the 111th Naval Construction Battalion walking on one of the main causeway highways at Utah Beach.