Ballast Water Management

Ballast Water Management – Deadline 31.12.2014

Since the introduction of steel hulled vessels around 120 years ago, water has been used as ballast to stabilize vessels at sea. Ballast water is pumped-in to maintain safe operating conditions throughout a voyage. This practice reduces stress on the hull, provides transverse stability, improves propulsion and manoeuvrability, and compensates for weight lost due to fuel and water consumption.

While ballast water is essential for safe and efficient modern shipping operations, it may pose serious ecological, economic and health problems due to the multitude of marine species carried in ships’ ballast water. These include bacteria, microbes, small invertebrates, eggs, cysts and larvae of various species. The transferred species may survive to establish a reproductive population in the host environment, becoming invasive, out-competing native species and multiplying into pest proportions.

The problem of invasive species in ships’ ballast water is largely due to the expanded trade and traffic volume over the last few decades and since the volumes of seaborne trade continue to increase the problem may not yet have reached its peak. The effects in many areas of the world have been devastating. The spread of invasive species is now recognized as one of the greatest threats to the ecological and the economic well-being of the planet.

After more than 14 years of complex negotiations between IMO Member States, the International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM Convention) was adopted by consensus at a Diplomatic Conference held at IMO Headquarters in London on 13 February 2004.

The Convention requires all ships to implement a Ballast Water and Sediments Management Plan. All ships have to carry a Ballast Water Record Book and are required to carry out ballast water management procedures to a given standard.

The specific requirements for ballast water management are contained in regulation B-3 Ballast Water Management for Ships and differ according to the age of the vessel and the ballast water capacity.

BWM Standards

There is a ballast water exchange standard and a ballast water performance standard.

Regulation D-1 Ballast Water Exchange Standard – Ships performing Ballast Water exchange shall do so with an efficiency of 95 per cent volumetric exchange of Ballast Water. For ships exchanging ballast water by the pumping-through method, pumping through three times the volume of each ballast water tank shall be considered to meet the standard described. Pumping through less than three times the volume may be accepted provided the ship can demonstrate that at least 95 percent volumetric exchange is met.

Regulation D-2 Ballast Water Performance Standard – Ships conducting ballast water management shall discharge less than 10 viable organisms per cubic metre greater than or equal to 50 micrometers in minimum dimension and less than 10 viable organisms per millilitre less than 50 micrometres in minimum dimension and greater than or equal to 10 micrometers in minimum dimension; and discharge of the indicator microbes shall not exceed the specified concentrations.

Other methods of ballast water management may also be accepted as alternatives to the ballast water exchange standard and ballast water performance standard, provided that such methods ensure at least the same level of protection to the environment, human health, property or resources, and are approved in principle by IMO’s Marine Environment Protection Committee (MEPC).

Ships constructed before 2009 with a ballast water capacity of between 1500 and 5000 have until 31.12.2014 to adopt regulation D-2 the Ballast Water Performance Standard.

By 31.12.2016 all ships will have to comply with regulation D-2

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