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Ballast water management:

How to get compliant by 2024

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We have gathered everything you need to know about the IMO ballast water management convention in a quick guide.

This e-book will also show you when to start planning in order to be compliant by 2024 ...


International Ballast Water Management convention

In the coming years, mobile drilling units, shipping operations and marine fleets, will be challenged to comply with the new Ballast Water Management (BWM) convention by the International Maritime Organization (IMO). This BWM convention requires many vessels to install a new and type approved ballast water treatment system (BWTS) by 7 September 2024.

IMO is the maritime regulatory agency of the United Nations and the IMO convention requires ballast water to be treated to specific standards prior to discharge. The convention entered into force on 8 September 2017 and applies to all vessels that carry ballast water across borders. The new rules state that all semi-subs, jack-ups, drill ships and vessels need to have an approved ballast water treatment system retrofitted at their first renewal survey after 8 September 2019. 

Under this convention, all ships and vessels in international traffic must manage their ballast water according to a ship-specific ballast water management plan. All ships must have a ballast water record book and an international ballast water management certificate. The ballast water management standards will be phased in over a period of time. 

Do not wait until the last minute ...

The Ballast Water Management convention requires you to comply with the convention at the latest by 7 September 2024. As a result, type approved systems, approved suppliers and shipyard slots are expected to be in high demand as we draw closer to 2024.

Therefore, it is important to know that putting off the installation of an approved ballast water management system until 2024 could result in issues with yard, material and supplier availability. This means that you might not be able to comply with the rules in due time. We expect that most of the IOPP renewals will take place from 2021-2023. You should start to plan ahead today! 

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What is "ballast water"?

Ballast water is used to maintain the vessel stability and to ensure vessel structural integrity.

As ships unload their cargo or move around heavy items onboard the vessel, ballast water is typically pumped in or transferred between tanks.

When water is then transported to other geographic areas, the discharge of ballast water in other ecological zones may result in the establishment of harmful aquatic organisms creating a detriment to the marine environment. This is globally recognized as a serious threat to the biological diversity and human health in general.

The threat of untreated ballast water

Ballast water is a threat to the marine environment due to the many marine species carried in ships’ and rigs’ ballast water. The problem is caused by vessels taking in ballast water in one location and discharging ballast water in a new location. Ballast water from other locations will hold alien bacteria, microbes, small invertebrates, etc. Invasive species carried in ballast water may survive to establish a reproductive population in the new host environment. Alien species risk out-competing native species and they multiply into pest proportions.

Ballast water will continue to be an inevitable part of international shipping operations and offshore operations, but the aim of the recent ballast water rules is to limit the impact on marine life by controlling ballast water management.

Read more


Know these BWM standards

As a vessel owner / mobile unit owner, you should invest some time in gaining a thorough understanding of the new requirements and regulations. However, in order to give you a quick overview, we have extracted some of the important elements that you need to act upon (see full convention here @IMO) Please keep in mind that some national governments and even local ports have defined their own ballast water management rules. Regulations B-3, B-4, D-1 and D-2 define the most significant rules for implementation of the ballast water management convention.

1. Ballast water exchange standards
B-4 and D-1 set the standard for ballast water exchange. B-4 states that ballast water exchange must take place in open sea, no less than 200 nautical miles from land and at > 200 m in depth. The D-1 standard requires an exchange method with efficiency of 95 per cent volumetric exchange of ballast water. The ballast water can be exchanged by sequential flow through or dilution methods.

Exchanging ballast water mid-ocean is an intermediate solution until the regulation is fully implemented. Eventually most vessels and mobile units will need to install an on-board ballast water treatment system.

2. Ballast water treatment performance standard
Regulation B-3 requires vessels to perform ballast water management using a type-approved treatment system that meets the performance standard defined in Regulation D-2.

In standard D-2, the IMO defines the permitted number of organisms and the allowed concentrations of indicator microbes in the discharged ballast water: “Ships conducting ballast water management shall discharge less than 10 viable organisms per cubic metre greater than or equal to 50 micrometres in minimum dimension and less than 10 viable organisms per millilitre less than 50 micrometres in minimum dimension and greater than or equal to 10 micrometres in minimum dimension; and discharge of the indicator microbes shall not exceed the specified concentrations.”

As an offshore asset owner, you have probably noticed that several types of water treatment technologies meet the D-2 standards. Some systems provide physical solid-liquid separation and others use chemical or physical treatment technologies. All vessels must be in compliance with the D-2 standard by the date of their first IOPP renewal survey following the BWM Convention’s entry into force on 8 September 2017 (read about the Alfa Laval system that uses UV technology).

Vessels and mobile units built prior to 8 September 2017, must be retrofitted with a type-approved ballast water treatment system that meets the above performance standard. New ships are required to have a type approve system installed at the time of delivery. Vessels that operate without a treatment system can be in compliance until their next scheduled dry docking by meeting the ballast water exchange standard described in Regulations B-4 and D-1.

D1 or D2 standards do not apply to ships that discharge ballast water to an approved reception facility.

3. Approval requirements
In addition to meeting the D-2 standards, the D-3 standard requires that ballast water treatment systems receive type approval from an IMO surveyor before it can be considered in compliance.

This rule applies to all systems, regardless of treatment technology. Approval is conducted in accordance with IMO guidelines.

Ships and vessels of at least 400 GT can expect regular inspections to ensure that regulations and procedures are followed. All ships and vessels must therefore be ready with the following:

  • An Approved and ship-specific Ballast Water and Sediments management plan. This plan must provide standard operational guidance for the planning and management of vessels’ ballast water and sediments and describe safe procedures.
  • A Ballast Water Record Book: Ballast water exchange and/or treatment should be recorded in this book. The record book can be electronic record system or be integrated into another system. Entries must be maintained on board the vessel for minimum two years after the last entry has been made.
  • A valid international Ballast Water Management Certificate.

Special US Coast Guard requirements

The “US Coast Guard (USCG) Ballast Water Discharge Standard” requires all vessels (that need to discharge ballast water in US waters) to have a ballast water treatment system that is type approved by the USCG. The standard defined by USCG is almost the same as the IMO regulation. This USCG rule also require installation of type-approved treatment system prior to deballasting in US waters.

However, for vessel owners it is important to understand that many IMO type approved treatment systems fail to meet the USCG requirements. Only few systems have been approved by both the IMO and the USCG - one example of such system is the PureBallast 3.2 by Alfa Laval!

Contact our Ballast Water Management specialists

Simon Wall

Semco Maritime A/S
Esbjerg Brygge 30
6700 Esbjerg

Nicolaj Bjerre

Operation Manager, Rig & Offshore

Semco Maritime Inc.
4321 Kingwood Dr. Suite 572
Kingwood, TX 77339