The published extension to the Panama Canal is now playing a significant role for the design of both container ships and bulk carriers. The extended canal, expected to be operational in 2014, will have locks measuring 55m wide and 427m long and a depth of 18.5m.

In the existing locks, electric locomotives are used to keep the ship positioned in the middle, power is provided by the ship’s propeller. Thus a narrow clearance of some 0.6 m on each side is sufficient. This system will not be used in the new locks. The ships that can be accommodated are bigger, and locomotives will be insufficient in weight and power to handle these bigger ships. Hence, tugs will be used. This will require more space in the locks. Hence, the new Panamax limits have been specified as: Length (Loa) = 366 m, beam (B) = 49 m and draft (T) = 15.2 m.

When comparing the lock dimensions we find a clearance on each side of 3 m, and over 30 m fore and aft. This is to allow for the maneuvering with tugs. Questions have already been raised as to the need for such big clearances. For design of the New Panamax container vessel (NewPX), some speculation is currently going on as to whether another container row can be added, bringing the max beam up to about 51 m. It seems likely that the final dimensions are not yet decided, and that there may be room for changes in the years to come.