Ballast water management (BWM) is principally concerned with preventing the spread of non-native aquatic species in lakes, rivers and coastal waters. DNV GL has been the leading body worldwide in type approval of ballast water treatment systems (BWTS) following the IMO Guidelines G8 for type approval. More than 25 systems are being tested and approved at different locations around the world.

DNV GL has become the first class society with status as Independent Lab (IL) accepted by the United States Coast Guard (USCG) to evaluate and test technologies designed to treat ballast water on ships. DNV GL can now offer approval services that will assist BW treatment system manufacturers to achieve type approval from the USCG, in addition to the already established IMO approval.

In 2004, IMO adopted the International Convention for the Control and Management of Ships’ Ballast Water and Sediments. The Convention will enter into force 12 months after it has been ratified by 30 states representing 35 percent of the world’s merchant shipping tonnage. The Convention will apply to all ships and offshore structures that carry ballast water and are engaged in international voyages.

The Ballast Water Management (BWM) Convention requires:

  • A ship-specific Ballast Water Management Plan approved by the Administration on board
  • A Ballast Water Record Book on board
  • Ballast water exchange (Regulation D-1)
  • An approved ballast water treatment system (Regulation D-2)
  • An International Ballast Water Management Certificate.

The Convention stipulates two standards for discharged ballast water. The D-1 standard covers ballast water exchange while the D-2 standard covers ballast water treatment. The Convention requires either D-1 or D-2 standard after entry into force. If entry into force occurs prior to 1st of January 2017, the Convention will require compliance with D-2 according to the schedule in the table:

Constructed yearBW Capacity (m3)New schedule
Before 2009Between 1500 and 50001st IOPP renewal survey after entry into force of the Convention
Less than 1500 or greater than 50001st IOPP renewal survey after the anniversary date of delivery of ship in 2016
2009 or afterLess than 50001st IOPP renewal survey after entry into force of the Convention
Between 2009 and 20115000 or more1st IOPP renewal survey after the anniversary date of delivery of ship in 2016
After 20115000 or more1st IOPP renewal survey after entry into force of the Convention

However, if the Convention enters into force after 31 December 2016, the applicable date of compliance with D-2 standard is first renewal survey for all ships. Ships built after entry into force will be required to have a treatment system installed at delivery.

The revised US Coast Guard (USCG) regulations on ballast water management entered into force 21 June 2012. US legislation requires the ballast water treatment system (BWTS) to be type approved by the USCG. Currently, no BWTS has such type approval.

All ships calling at US ports and intending to discharge ballast water must either carry out exchange or treatment, in addition to fouling and sediment management. The exchange of ballast water will only be allowed until the implementation deadlines for treatment systems as shown in the table below. A third option is to use potable water (from the US public water system) and in such case the ballast tanks need to be cleaned and sediments removed beforehand.

Implementation schedule for the USCG ballast water treatment standard

Vessel's ballast water capacityDate constructedVessel's compliance date
New vesselsAllOn or after 1 December 2013On delivery
Existing vesselsLess than 1500 m3Before 1 December 2013First scheduled drydocking after 1 January 2016
1500 - 5000 m3Before 1 December 2013First scheduled drydocking after 1 January 2014
Greater than 5000 m3Before 1 December 2013First scheduled drydocking after 1 January 2016

Treatment must be done using either a USCG type-approved system or a system type approved by another Administration which the USCG has accepted. This is referred to as AMS. The USCG treatment discharge standard is the same as the IMO Ballast Water Management Convention D-2 Standard.

Additional requirements for USCG
The new USCG regulations also contain some additional requirements to the ship’s operation, which are summarised below:

  • Clean ballast tanks regularly to remove sediments.
  • Rinse anchors and chains when the anchor is retrieved.
  • Remove fouling from the hull, piping and tanks on a regular basis.
  • Maintain a BWM Plan that includes the above in addition to ballast water management (no requirement that the BWM Plan must be approved).
  • Maintain records of ballast and fouling management.
  • Submit a report form 24 hours before calling at a US port.

DNV GL is leading a partnership between DHI Denmark, Golden Bear in California, Delta in Denmark and Applica Test & Certification AS to test and evaluate systems to the USCG requirements. More test facilities are in the pipeline to be added to DNV GL’s network of sub-contractors worldwide.

DNV GL Services
DNV GL has wide knowledge of and expertise in ballast water management and treatment technologies. In order to support shipowners and manufacturers, DNV GL has developed a range of different services related to BWM:

  • IMO type approval of Ballast Water Treatment Systems
  • Evaluation, inspection, and testing of BWMS for type approval on behalf of USCG as an IL
  • Safety assessment of Ballast Water Treatment Systems
  • Approval of Ballast Water Management Plans
  • Approval of retrofit installation of Ballast Water Treatment Systems
  • Approval of test facilities engaged in environmental testing of BWMS
  • Approval of test facilities engaged in land-based and shipboard testing of BWMS

Approval programmes and DNV rules for installation of BWMS can be found under "Related information" on the right hand side.

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