Our field of expertise

Mooring caisson removal

Five caissons which until recently have been used to moor the spare lock gate of the Noordersluis have lost their purpose and needed to be removed and transported to a new location.


To remove and transport the caissons safely and efficiently to a new destination. HAPO International Barges B.V. has awarded Saltwater Engineering to perform transport engineering by deploying their H-332 barge which is fitted with the PLM 15000 E ringer crane.


Safety first

First a rigging plan, with a custom designed lifting beam, and a loading plan are developed to fully utilize the barge. SPMT’s are being deployed to shift two of the caissons on deck because the available crane capacity is not sufficient to position all caissons by lifting only. In addition, a seafastening design and deck strength verification is performed and merged into a stowage plan to ensure safe transport.

One of the main challenges was to create lifting points to enable the crane to hook up efficiently onto the caissons. In close cooperation with civil engineering company IBT B.V. the solution has been found to design custom trunnions which will be slid into pre-drilled holes of the upper part of the caissons.

In all performed engineering elements Saltwater has shown to be able to find custom solutions which fully fit the client’s needs and capabilities, without losing sight of quality and cost efficiency.

Removal of 5 caissons at Ijmuiden.
Removal of 5 caissons at Ijmuiden.

Specific project data

Project information


  • Rigging plan
  • Lifting beam design
  • Loading plan
  • Sea fastening design
  • Deck strength verification
  • Stowage plan
  • Lifting points design