The Royal Canadian Engineer units assigned to the Normandy landings consisted of the 5th Field Company of 1st Army Troops, and from the 3rd Canadian Division; the 6th, 16th and 18th Field Companies and the 3rd Field Park Company. The 5th Field Company and one section of the 18th had the vital role of clearing underwater and other landing obstacles while the other units were to help the Division get ahead once it landed. The Royal Navy cleared obstacles in more than three feet of water while the Royal Engineers attached to the Canadians gathered or destroyed obstacles in shallow water where an elaborate minefields had been laid.
Due to the late landings and a higher than expected tide, clearing the beach obstacles was badly disrupted and was mostly delayed until the receding tide uncovered the obstacles. The high sea-wall combined with enemy fire caused trouble but the 5th Assault Regiment Royal Engineers who were assigned to support the 3rd Canadian Division assault employed specialized armoured vehicles and eventually cleared four exits by either breaking down the wall, clearing obstructed ramps or by laying assault bridges over the wall.
The Royal Canadian Engineers suffered heavy casualties as they laboured to remove charges from the beach obstacles while under fire, but by the evening the engineers had cleared a 40-yard gap on Mike sector and a 1600-yard gap on Nan sector.