The Task:

Marlin was commissioned to carry out a Ballast Water Treatment Unit (BWTU) service on board the cruise vessel Marella Explorer while the ship was operating overseas in Corfu. Ballast Water Treatment Systems are a highly specialised area of marine environmental compliance, designed to ensure vessels meet international regulations for preventing the transfer of invasive aquatic species through ballast water discharge.

Due to the technical nature of these systems, servicing must be carried out by experienced engineers who understand both the mechanical and UV treatment components involved. The project required rapid international mobilisation to meet the vessel during its operational schedule abroad.

What We Did:

Our engineers travelled to Corfu to board the vessel and conduct a comprehensive inspection and service of the ballast water treatment system.

The work included:

• Full inspection of the UV chamber assemblies and confirmed there were no visible leaks.
• Testing of all UV lamps, which were confirmed to be operating correctly.
• Inspection of the wiper plate magnet and indication system.
• Examination of the POD filter discs, where debris accumulation on the outer surfaces was observed as expected, while the filter faces themselves remained clean.
• Assessment of the pumps and system operation, verifying correct operation while identifying a loose guard requiring attention.
• Checked that the backflush cycle operated correctly, ensuring the filtration system was functioning as designed.

The Outcome:

The ballast water treatment system was confirmed to be operating correctly and in good overall condition following inspection and testing. Minor observations were recorded, including a loose guard on the backflush pump, allowing the vessel’s engineering team to address the issue proactively before it developed into a larger problem.

Marlin has the capability to mobilise internationally at short notice, supporting marine operators wherever vessels are operating. Our expertise in specialist BWTS servicing ensures vessels remain compliant with international environmental regulations while maintaining reliable system performance.