Portable working deck

A working deck configured to access offshore well heads, the working deck comprising:

• a barge having an upper surface, wherein the upper surface of the barge is parallel to a surface of water on which the barge is floating;
• and
• transverse beams fixed to the upper surface of the barge;
• wherein:
• the working deck comprises at least two cantilever beams attachable on to the transverse beams;
• and
• a work platform comprising removable floor panels for accessing the well heads, wherein the work platform is positioned on the at least two cantilever beams and being movable in a lateral direction of the cantilever beams wherein the transverse beams are oriented perpendicular to a forward direction of the barge and comprise at least one of a track beam and one of a hold-down beam for receiving the at least two cantilever beams, wherein the at least two cantilever beams are able to be moved along the at least one track beam and the hold down beam to change the position of the at least two cantilever beams relative to the barge, wherein the working deck comprises a plurality of stiffening elements for stiffening the hold-down beam and to prevent or limit deformation of the hold-down beam.