Ballast Water: A Marine Pollution Often Unknow
Ballast Water play an important role in the safety and stability of ships. Unfortunately, introduction of invasive species through ballast water discharge has been a serious concern for marine ecosystem.
An unrecognized marine pollution
With the loading and unloading of untreated ballast water, vessels become a vector for the transfer of organisms from one part of the world to another.
Thus, maritime traffic contributes to the introduction of organisms alien to the local ecosystem, causing significant ecological problems that can also affect coastal health and economy.
What is ballast water used for?
It is fresh or saltwater held in the ballast tanks and cargo holds of ships.
It is used to adjust the overall weight of the vessel and its internal distribution in order to keep the ship floating safely. To take an example, on a journey when ships are not carrying cargo, full ballast tanks filled are required to remain stability in rough seas.
Ballast water management is an emerging environmental issue.
This water contains a significant concentration of potentially pathogenic organisms and micro-organisms (viruses and bacteria). Discharge of this water without appropriate treatment encourages the introduction of new exogenous and invasive species that can contribute to the disruption or weakening of certain marine and river ecosystems.
Facts and figures :
- 10 billion tonnes of ballast water are transported around the world every year and fill about 4 million Olympic-sized swimming pools;
- 7,000 species are transferred into ballast water every hour of every day;
- A new invasive species is introduced every nine weeks.
Some animals such as green crab, zebra mussel and round goby are examples of marine invasive species found in Canadian waters. To learn more about these and other aquatic invasive species introduced through ballast water, click here.
New international awareness
In response to this, the International Maritime Organization (IMO) developed the “International Convention for the Control and Management of Ships’ Ballast Water and Sediments”. The agreement was adopted in 2004 and entered into force in September 2017.
Why so late?
For this international convention to enter into force, it had to be ratified by at least 30 states, representing more than 35% of the world fleet (a qualified majority). After more than 10 years, the convention was finally approved the 8th of September 2017 with the ratification of Finland.
The Convention consists of 22 articles, accompanied by an annex that sets out rules, about control and management of ships’ ballast water and sediments. These new provisions determine the obligations of States and ships in this area.
An International Convention to offer a global response to this crucial issue
This international maritime treaty requires signatory flag states to ensure that ships flagged comply with standards and procedures for the management and control of ships’ ballast water.
However, the solutions recommended by the Convention come up against obstacles due to the complexity of deballasting on the high seas and the current lack of satisfactory water management processes.
From 2024, all ships are required to have approved Ballast Water Management Treatment System, according to the D2 standard (usually through the use of a ballast water treatment system). Regulations include a change from the old way of managing ballast water (exchanging ballast water in mid-ocean, which strands organisms in a hostile environment) to modern ballast water management systems (that treat ballast water to minimize the number of organisms).
On June23, the Ballast Water Regulations came into force in Canada. Established under the Canada Shipping Act, it is a way for Canada to protect its environment and economy from aquatic invasive species.
At the national level, France ratified the convention in May 2008. The law for the reconquest of biodiversity ensuredits implementation.
Today, they are 314 known alien marine species on the French coastline!