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Sector Insights

The Ballast Water Management Convention: an update

07.06.2019 Maritime

Rory Macfarlane

Rory Macfarlane Partner

Whatever your view on BWM, it is here and is here to stay. In this article, we summarise the key requirements for BWM and then take a look at some of the practical problems the industry has encountered in the last 18 months.

“The biggest challenge is matching the additional power and space requirements when retro-fitting into existing vessels”
 “PSCs must be instructed not to overly rely on the new regulations to hinder shipowners’ smooth operations”
“A waste of time and money to appease the vocal environmental lobby with limited benefit and no return on investment”

Three quotes from three clients when asked to summarise their view on Ballast Water Management (“BWM”) in one sentence. Whatever your view on BWM, it is here and is here to stay. In this article, we summarise the key requirements for BWM and then take a look at some of the practical problems the industry has encountered in the last 18 months.
Most owners and operators should be familiar with the requirements of the Ballast Water Management Convention (“the Convention”) as it has been in force since 8 September 2017. However, a second key date is imminent. Vessels that were in existence prior to 8 September 2017 are required to move from ballast water exchange to ballast water management by their first IOPPC renewal after 8 September 2019. It should be noted that the US has a separate and more stringent regime than that which is set out by the Convention and the implementation of that regime is unaffected by the requirements of the Convention. Shipowners whose vessels trade in the US are reminded that they still must ensure that they comply with the current US legislative requirements.
Our previous articles have covered the requirements of the Convention in detail. However, by way of reminder, we set out below a simplified summary of a shipowner’s key obligations. 

The Convention

The Convention’s aim is to protect marine ecosystems by preventing the spread of potentially harmful aquatic organisms transported in vessels’ ballast water. The regime requires ships to manage their ballast water so that such organisms and pathogens are removed or rendered harmless before the water is released into a new location. It applies to all ships which use ballast water during international voyages and which are registered under contracting parties to the Convention. There are some narrow exceptions (such as ships that trade only within the waters of a single contracting state), but most of the world’s trading fleet must comply.

 The Convention also makes clear that port states which are contracting parties are to apply the rules of the Convention to all ships as necessary so as to ensure that ships flying the flag of non-contracting parties do not enjoy more favourable treatment. The definition of vessel is fairly wide and extends to submersibles, floating craft and platforms, FSUs and FPSOs.  
The Convention falls broadly into two parts. The main body of the Convention (Articles 1 to 22) deals with the obligations on member states. Then there is the Annex that contains the provisions (Regulations A-E) with which owners must comply. These impose both documentary requirements and system requirements.
Documentary requirements
All vessels subject to the Convention must have on board an international BWM Certificate. To obtain this, owners will need a flag-state approved ship specific BWM Plan. Each vessel must also carry a BWM Record Book. 
System Requirements
There are two options under the Convention: Ballast Water Exchange and Ballast Water Management. Both have a procedure (Annex: Regulation B) and a prescribed standard (Annex: Regulation D). 

The “exchange” standard is found in Regulation D-1. It was included as a temporary solution to be used until all relevant vessels become obligated to meet the “performance” standard required for full Ballast Water Management. It essentially requires exchange to be conducted in the open seas, although the extent to which this is reasonable, or operationally practical, is controversial.

The standard for ships operating Ballast Water Management is found in Regulation D-2. This D-2 performance standard specifies a maximum amount of viable organisms allowed to be discharged into the sea within a prescribed volume of water. To conform to this standard, most ships will require specialist flag-state approved equipment. If the system uses an active substance as part of the treatment process, then this too will need flag-state approval.

Operating problems – some recurring themes

At an industry event in Singapore last year, Intertanko indicated that between 60% and 80% of its members reported that the systems installed on their vessels were not working correctly; failures were becoming a daily occurring problem. Industry reports suggest that the reasons behind these failures can be divided broadly into the three following categories:

Poor installation
As many as 50% of problems encountered with BWM systems could have been avoided by more careful selection and installation. Thought must be given to both how the ship intends to trade, as well as its compatibility with the existing ballasting system. Owners yet to install systems on their ships should ensure that they use experienced superintendents to oversee the system selection and installation work.

Cost-cutting on equipment
Type approval and system robustness are not necessarily the same. The more recent systems coming to market tend to use more resilient components. However some operators have sought to reduce the operational cost of instalment by using cheaper parts for equipment considered by Class to be non-essential (piping, sensors, valves etc.).  

This approach may prove to be a false economy. Whilst this may reduce costs in the short term, in the long term it will lead to increased maintenance costs and a greater risk of system failure culminating in regulatory sanction.  

Operation and maintenance

Many vessels have had ballast water management systems in place for several years, but have not to date been mandated to operate them. This has often resulted in their maintenance being overlooked. Owners are now finding out that these systems are not operating correctly, require costly repairs and, in some cases, their replacement. 

Owners must ensure that the vessel’s chief engineer fully understands the rationale behind the systems installation and precisely how to operate and maintain it.


Whilst the Convention is relatively straightforward as a piece of legislation, as always the devil is in the detail of compliance. Not for the first time in recent history, the maritime industry is having to meet the substantial practical and financial challenges of regulatory change. 

Even properly installed, well-designed systems can have shortcomings. Some filtration screens may not be adequate to remove smaller marine organisms. Some of the popular biocides (active substances) may only be available in specific ports or regions. The effectiveness of systems using UV treatment methods can be compromised by murky water and high levels of suspended particles. Whilst space restrictions will rule out certain systems during retro-fitting, owners may also need to consider the vessel’s likely trading pattern to avoid problems post-instalment.

As 8 September 2019 comes and passes, and more of the world’s fleet transitions to full Ballast Water Management, we can expect to see the instances of vessel detention and regulatory sanction increase.

A reliable system and well-trained crew will be an owner’s first, and most important, line of defence.

This article was drafted with assistance from Clare Birchenhough.

Article authors:

Rory Macfarlane