Ballast water is water carried in ships’ ballast tanks to improve stability, balance and trim. It is taken up or discharged when cargo is unloaded or loaded, or when a ship needs extra stability in foul weather.
When ships take on ballast water, plants and animals that live in the ocean are also picked up. Discharging this ballast water releases these organisms into new areas where they can become marine pests.
Ballast water management
The Victorian domestic ballast water management system is designed to protect Victoria’s marine environment by minimising the risk of introduction of marine pests via ships’ ballast water. Such pests can have significant impacts on the community's use of our waters, lead to trade restrictions and affect other growing industries, such as aquaculture. An example is the significant impact that the Northern Pacific seastar from Tasmania has had on Port Phillip Bay since it was discovered in the late 1990s.
Victorian domestic ballast water management arrangements were introduced by the Victorian Government in 2004. They are outlined in the Waste Management Policy (Ships’ Ballast Water), which forms part of Victoria’s legal system.
EPA has produced a CD for shipping operators and agents that provides a user’s guide on domestic ballast water obligations in Victoria under the Environment Protection (Ships’ Ballast Water) Regulations 2017.
EPA’s Protocol for environmental management: Domestic ballast water management in Victorian state waters (publication 949) explains how ships can meet their ballast water obligations set out in the policy, and is included on the ballast water CD.