Possible Solutions

Since the 20th century, many exotic animal and plant species have been introduced into the Great Lakes-St. Lawrence Basin. This phenomenon has accelerated over the past 30 years. To protect Canadian waters, ballast water management practices have been modified.

In 2001, the Ballast Water Control and Management Regulations were introduced as part of the Canada Shipping Act. In 2004, the International Maritime Organization adopted the International Convention for the Control and Management of Ships' Ballast Water and Sediments, which came into effect in 2005.

Current Canadian regulations require all ships entering Canadian waters to conduct mid-ocean ballast water exchange in zones located off the Atlantic coast. This procedure replaces fresh water with salt water, ejecting exotic organisms. If freshwater species remain in the tanks, they are not generally able to survive the increased salinity. However, certain species can survive in both fresh and salt water, and are therefore more difficult to eliminate.

Ballasting and unballasting operations must not compromise the safety and maneuverability of the ship. To increase the safety of such operations, the use of flow-through exchange systems has been proposed. These systems simultaneously add and discharge ballast water, allowing it to be exchanged without affecting the ship's stability.

However, ballast exchange does not eliminate all exotic organisms in residual water and sediments. Regular, systematic rinsing of the ballast tanks with salt water could help get rid of such residues.

The hulls of pleasure craft must be cleaned regularly to avoid spreading invasive species. This also applies to fishing boats and gear.