It was never realistic to assume that treated ballast water would not contain any viable organisms when discharged.

The G8 guidelines, which set out the type approval process for ballast water management systems, were first agreed at the IMO before any systems had even been developed.

The IMO has been dealing with the problem of invasive species being transported around the world in ballast water for decades. The issue was already on the radar in the 1970s. At MEPC 31 in 1991, the IMO adopted voluntary guidelines that focused on not releasing ballast water, exchanging ballast water or discharging it into shore-based reception facilities. On-board treatment systems were mentioned as a possibility for future research.

In the years following the adoption of the Ballast Water Convention in 2004, the types and number of treatment systems grew, with over 80 receiving type approval. However, G8 specified a limited salinity range for testing these systems, and there were no requirements to conduct tests using fresh water or different water temperatures. There were also concerns about the need to monitor the effectiveness of the disinfection process for only five days. In any case, G8 was only a guide, and results could reflect the individual nature of the test water obtained near a particular test house.

Then the U.S. Coast Guard rejected a treatment that rendered organisms permanently unusable but not necessarily dead. This resulted in OEMs using UV treatments having to meet two different standards to gain global approval for their systems.

Fast forward to MEPC 81 in March of this year, six months before all ships must meet the D-2 standard (which requires treatment, not just replacement), depending on the anniversary of the survey, and the details are still being worked out. After long discussions and three rounds of voting, the text for the interim guidelines for ships ballasting in challenging, sediment-rich waters was finally approved.

After long discussions and three rounds of voting, the text for the interim guidelines for ballasting ships in challenging, sediment-rich waters was finally adopted at MEPC 81. Image courtesy of IMO

The nature of the animal

Controlling invasive species is an ongoing battle against the diversity and tenacity of life. The black goby embodies the ability of some species to not only survive but thrive in new environments. It is a voracious and aggressive fish; a well-known invader that has been introduced into many countries. Originally from the Black and Caspian Seas, it thrives in varying salinities, warm or cold water, and a wide variety of foods.

The species is now native to the Great Lakes, along with zebra and quagga mussels and other species, many of which are thought to have arrived in the country in ballast water. Since ballast water exchange by ships before entering the Strait was fully implemented, no new cases of invasive species have been reported. However, inland fishermen operating only within the Strait have further spread the already introduced species. A study published this year found that untreated samples from inland fishermen can contain thousands of eggs or resting stages of organisms per cubic meter of ballast water.

Despite its success on the Great Lakes, ballast water exchange is not considered sufficient because even ships without ballast on board have been found to contain living organisms in the deposits at the bottom of the tanks, which are excreted when the ship is re-ballasted.

Focus on performance

It is tempting to think that the effectiveness of treatment systems has improved over time as the industry has evolved and regulations have become more stringent. A study of 228 vessels during 2017-2023 found that this was not the case. Almost all vessels met the D-2 standard for indicator microbes and organisms

Inspection house SGS has played a key role in developing sampling and testing procedures to collect representative samples of the large quantities required to verify that ships’ wastewater meets the D-2 standard. The company has conducted compliance testing and commissioning tests on over 2,000 vessels worldwide.

“Our sampling experts often work alongside crews during sampling operations, providing valuable training,” says Cameron Talbot, Australian Marine Services Manager at SGS Australia. “As compliance and voluntary due diligence sampling become more widespread, I expect crews will gain expertise in critical sampling aspects such as filtrate disposal and sampling point maintenance. Regular sampling also provides vessel operators with greater insight into whether their systems and procedures meet the D-2 performance standard, leading to higher compliance rates and improved protection of the marine environment.

“Currently, compliance is often assumed rather than verified.” He says many port state controls may need support in building capacity for this task or need to work with specialised, accredited laboratories.

Shipowners who are put in the situation of having to circumvent the system are often considered “guilty” and can get a bad reputation in environmental terms.
Manoj Subramanian, International Chamber of Shipping (ICS), Technical Advisor for Maritime Transport
Image courtesy of ICS

Pointing the finger

By 8 September 2024, an estimated 40,000 vessels will be fitted with a treatment system. The phased approach to compliance between the entry into force on 8 September 2017 and 8 September 2024 was widely seen as a victory for common sense, as it gave OEMs, shipyards and shipowners time to install so many systems.

However, this was also the start of more problems for ship owners. Manoj Subramanian, technical advisor to the International Chamber of Shipping (ICS), says it is still common for a ballast water management system to be bypassed during ballasting, and it is becoming increasingly difficult for the relevant parties to figure out what went wrong, who was at fault and how to improve the situation. It is important to note, he says, that if the ballast water management system is bypassed, it is significantly more difficult for the ship to meet D-2 standards.

“Shipowners who are put in a position where they have to circumvent the system are often seen as ‘guilty’ and can get a bad environmental reputation as this is seen as opting for an inferior, cheaper ballast water management system but puts them in a difficult regulatory situation.

“Instead of blaming shipowners alone for circumventing the system, the inherent deficiencies of the system must be addressed. Therefore, ICS strongly advocates for a more consistent regulatory approach that leads to a more consistent and stringent set of requirements, from the type approval phase of a system through to the implementation phase of the Ballast Water Management Convention.”

ICS has identified several main reasons why crews circumvent their ballast water management system: lack of knowledge of the equipment on board the vessel and gaps in the information in the manufacturer’s manual, lack of timely support, machinery not suitable for real-world use and lack of availability of spare parts.

Redrawing the fronts

An experience-building phase was initiated at MEPC-71 in 2017, followed by the approval of a review plan at MEPC-80 in 2023, allowing for amendments to the Convention in 2026.

“This is 10 years too soon,” says industry veteran William H. Burroughs, founder and CEO of Monstrant Viam, who has worked on various class, OEM development, research and regulatory development projects. “In fact, we have only just started talking about problematic water quality and malfunctioning ballast water treatment systems. That will not be resolved for a decade or more.”

Amendments to the Convention are currently being drafted. It is important to obtain approval for the use of mobile BWMS, either for emergency response or for portable systems shared by a fleet of vessels.”

It advocates the recognition of “ballast water receiving” treatment systems that have pipelines that allow ships to discharge ballast water on land.

“These upgrades represent 10% of the cost of installing a ballast water management system and are nothing compared to the lifetime maintenance and operating costs of a system.”

Shore-based treatment systems will serve a regulatory purpose when shipboard systems fail to meet D-2, and they could also be a source of pretreated, fully IMO-compliant ballast water for ships, he says. But that would require a change in U.S. Coast Guard regulations.

In reality, we have only just begun to talk about problematic water quality and malfunctioning ballast water treatment systems.
William H. Burroughs, Founder and CEO of Monstrant Viam
Image courtesy of Monstrant ViamAn unnoticed victory

At present, there is little point in trying to determine whether the number of invasive marine species is declining. Such studies are difficult at best, as is concluding that a species was introduced through ballast water when other mechanisms (biofouling, release into aquariums, etc.) are also possible. And by definition, the Convention’s limits on the number of viable organisms that may be introduced are above zero.
If the transmission rate of potentially invasive species will never reach zero, are complex, expensive and time-consuming containment measures worthwhile? Organizations such as the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services might point to the billions of dollars lost in infrastructure and biodiversity as a justification for action, but a study of the port of Douala in Cameroon offers port states a more targeted approach.

Ninety-five percent of Cameroon’s goods are delivered by sea, and Douala receives ballast water from 41 ports and 20 ecoregions. Using specific trade routes, such as those from Antwerp, Durban, and Dakar, the researchers identified the invasion risks that could be mitigated by adhering to the D-2 standard. They modeled the likelihood of a species being alien based on biogeographical differences; the likelihood of its introduction based on ballast water volume, travel time, and treatment efficiency; and the likelihood of its establishment based on similar factors such as salinity and water temperature between the two ports. They concluded that the D-2 standard would reduce the likelihood of a biological invasion in Douala by at least 97%. At least 97%, but not 100%.