American Coatings Association

BWM Global Treaty to Halt Invasive Aquatic Species Now in Effect


The International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM Convention) went into effect on Sept. 8, 2017. The BWM Convention seeks to stop the spread of potentially invasive aquatic species by requiring ships to manage their ballast water to remove, render harmless, or avoid the uptake or discharge of aquatic organisms and pathogens within ballast water and sediments.

The BWM Convention was adopted in 2004 by the International Maritime Organization (IMO), the United Nations’ specialized agency with responsibility for developing global standards for ship safety and security and for the protection of the marine environment and the atmosphere from any harmful impacts of shipping.

The International Paint and Printing Ink Council, for which ACA serves as Secretariat, works on this issue through its Marine Coatings Technical Committee (MCTC). The MCTC is currently examining whether increasingly aggressive ballast water treatment systems using active substances that are anticipated to be installed as a result of this Convention could potentially impact ballast talk linings currently subject to approval under the IMO’s Performance Standard for Protective Coatings requirements.

Ballast water is routinely taken on by ships for stability and structural integrity. It can contain thousands of aquatic microbes, algae and animals, which are then carried across the world’s oceans and released into ecosystems where they are not native. Untreated ballast water released at a ship’s destination could potentially introduce new invasive aquatic species. Expanded ship trade and traffic volume over the last few decades have increased the likelihood of invasive species being released. Hundreds of invasions have already taken place, sometimes with devastating consequences for the local ecosystem, economy and infrastructure.

Under the BWM Convention all ships must carry a ballast water record book and an International Ballast Water Management Certificate. All ships engaged in international trade are also required to manage their ballast water to avoid the introduction of alien species into coastal areas, including exchanging their ballast water or treating it using an approved ballast water management system.

Initially, there will be two different standards, corresponding to these two options:

  1. The D-1 standard requires ships to exchange their ballast water in open seas, away from coastal waters. Ideally, this means at least 200 nautical miles from land and in water at least 200 meters deep. By doing this, fewer organisms will survive and so ships will be less likely to introduce potentially harmful species when they release the ballast water.
  2. D-2 is a performance standard which specifies the maximum amount of viable organisms allowed to be discharged, including specified indicator microbes harmful to human health.

New ships must meet the D-2 standard from Sept. 8, 2017, while existing ships must initially meet the D-1 standard. An implementation timetable for the D-2 standard has been agreed, based on the date of the ship’s International Oil Pollution Prevention Certificate (IOPPC) renewal survey, which must be undertaken at least every five years.

Eventually, all ships must conform to the D-2 standard. For most ships, this involves installing special equipment.

Shipboard ballast water management systems must be approved by national authorities, according to a process developed by IMO. Ballast water management systems have to be tested in a land-based facility and on board ships to prove that they meet the performance standard set out in the treaty. These could, for example, include systems which make use of filters and ultraviolet light or electrochlorination.

Note that the coming into force of the BWM Convention has no impact on the requirement to comply with existing U.S. Coast Guard requirements, which differ in some important respects from the IMO requirements and are imposed on ships in U.S. waters under U.S. port state authority.

Per the IMO, to date, more than 60 ballast water treatment systems have been given type approval.

Contact ACA’s Allen Irish for more information.