Positioning A Caisson
It takes several hours to maneuver each caisson into its final position. The first phase is the approach from the anchoring point, followed by positioning the caisson in the water above the area where it will be placed on the seafloor. It is then ballasted and submerged with the base of the caisson resting in 20 meters of depth. This is accomplished with topographic monitoring systems which are read and interpreted by a survey manager who relays the positioning information to the commander controlling the tugboat cables which actually move the structure.