Ballast Water Management

Do you need a ballast water management (BWM) system?  The IMO Ballast Water Management convention entered into force on 8 September, 2017.  But to make matters more confusing, all US vessels are also subject to the USCG ballast water rules, which are different. 

How are the Coast Guard ballast water management (BWM) regulations and IMO BWM Convention different?

(FAQ from USCG Website)

The main difference between the Coast Guard BWM regulations and the International Maritime Organization (IMO) BWM Convention is in the equipment testing and verification protocols. In 2005, as updated in 2008, the IMO released G8 Guidelines for the type approval of ballast water management systems (BWMS) by flag administrations. At present, these are recommendatory guidelines, as they have not come into force as a mandatory code yet. The guidelines are applied differently by flag administrations, and they do not require type approval testing to be conducted by an organization independent of the manufacturer. In contrast, U.S. type approval testing procedures are mandatory, detailed, and specify testing that is independent from manufacturers.

It is important to note that the ballast water discharge standards in the Coast Guard regulations and the IMO BWM Convention are similar, but not the same. The discharge standard in regulation D-2 of the BWM Convention is written in terms of “viable” (meaning able to reproduce) organisms, while the Coast Guard’s discharge standard is written in terms of “living” organisms. Also, as noted here, the testing requirements to prove that a BWMS meets the discharge standards are different.

Not All Systems are Equal

There are several different technologies for ballast water treatment.  Good operation depends on selecting the right system for your application.  If you select the wrong system, the costs can compound:

  • Extra power to UV lamps – more fuel burned in the generators
  • Replace UV lamps more frequently – $10k+ each time
  • Change filters more frequently
  • Constantly purchase chlorine or other chemical treatments
  • Purchase neutralizer to cancel out the chemicals you just injected
  • Pay pollution fines because the system didn’t work

To control these costs, you need to select the right system for your application.  The effectiveness of each technology depends on the water temperature, salinity, vessel voyage length, and a host of other factors. 

DMS has experience with the detailed investigation of these BWM systems.  Nicholas Barczak, a senior engineer at DMS, once worked on a detailed study to compare various technologies for ballast water treatment.


Ballast Water Treatment, US Great Lakes Bulk Carrier Engineering and Cost Study – Volume 2: Analysis of On-Board Treatment Methods, Alternative Ballast Water Management Practices, and Implementation Costs


Select the right system for your operational needs.  That selection starts with hiring DMS to support you.

A Plan for Ballast Water Management

The best system depends on the operational profile of your vessel.  DMS has extensive experience comparing systems from all major vendors.

  • Vendor comparison and selection
  • Machinery space arrangements
  • Foundation designs
  • Piping diagrams
  • Regulatory assessment

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