How did the eastern breakwater at Dunkirk help evacuate troops?

During the Dunkirk evacuation, the eastern breakwater served as a vital, makeshift dock that significantly accelerated the rescue of Allied troops.1

After Luftwaffe raids destroyed the port's primary facilities, Capt. William Tennant—the designated "beachmaster"—determined that evacuating soldiers directly from the shallow beaches was too slow and arduous. He identified the eastern breakwater, which stretched approximately 1,400 yards (1.3 km) into the sea, as a superior alternative. Topped with a wooden boardwalk and wide enough for a column of troops to march four abreast, the structure allowed rescue ships to moor alongside it.21

By directing the bulk of the evacuation efforts to this breakwater, approximately 200,000 troops were able to board vessels more efficiently than those waiting on the open beaches. Ultimately, this tactical decision was instrumental in the successful rescue of over 338,000 Allied soldiers during Operation Dynamo.123