Water bodies worldwide are being invaded by non-native aquatic species. Ballast water is one of the primary vectors for aquatic nuisance species invasions. Most vessels carry ballast water for stability when they are without cargo, but discharge ballast water after they have loaded with cargo. Although many species seem much too large to be transported by ballast water, the majority of marine organisms have a small larval stage that is an ideal size to be sucked into a ballast tank and transported to the next port of call. Under the right conditions and without natural predators and parasites, non-native populations can increase dramatically, threatening or displacing native species and radically changing the natural ecosystem. Click here to download the ten most unwanted species.

In 1997, the member countries of IMO adopted voluntary ballast water management guidelines to minimize the risk of spreading aquatic nuisance species. The guidelines recommend that vessels exchange ballast water collected in coastal waters with mid-ocean water on depth of more than 2000 meters. In February 2004, the member countries of IMO adopted a binding international agreement for mandatory ballast water management which mandates a ballast water discharge standard. Click here to download Resolution A.868(20). Argentina, Australia, Canada, Chile, Israel, New Zealand, United Kingdom and United States all have legislated their national quarantine requirements of ballast water.

The highlight of the IMO Resolution A.868(20) standard
• Each ship that carries ballast water should be provided with her own specific ballast water management plan
• The plan should address relevant part of these guidelines, approval documentation relevant to treatment equipment, an indication of records required, and the location of possible sampling points
• Procedures of each member country that has its own ballast water management standard
• Reception and treatment facilities should be made available for the environmentally safe disposal of ballast tank sediments
• Discharge of ship's ballast water into port reception and/or treatment facilities may provide an acceptable means of control
• Ship should maintain appropriate records of ballasting and/or de-ballasting such as: date, tank location, tonnage, ship position, water temperature and salinity, etc. when taking on or discharging ballast water
• Ship should have her ballast water reporting form that contains ship information, ballast water on board and total capacity, ballast water tanks, ballast water history, etc.
• The uptake of ballast water should be minimized or where practicable, avoided in areas and situation such as: in or near marine sanctuaries, marine preserves, marine parks, or coral reefs, near sewage outfalls or dredging operations, areas identified by the member countries, in darkness when bottom-dwelling organisms may rise up in the water column, in very shallow water, or where propellers may stir up sediments, where tidal flushing is poor or when a tidal stream is known to be more turbid. Rinse anchors and anchor chains during retrieval at their place of origin
• Where practical, routine cleaning of the ballast water to remove sediments should be carried out in mid-ocean or under controlled arrangements in port or dry dock
• If it is necessary to take on and discharge ballast water in the same port to facilitate safe cargo operations, care should be taken to avoid unnecessary discharge of ballast water that has been taken up in another port
• When practicable, ships should conduct ballast water exchange in deep water (at least 2000 meter depth), in open ocean and as far as possible from shore (at least 200 nautical miles from shore)
• Where the flow-through method is employed in open ocean by pumping ballast water into the tank and allowing the water to overflow into ocean, at least 3 times the tank volume should be pumped through the tank
• In cases where ballast water exchange or other treatment options are not possible, ballast water may be retained in tanks. Should this not be possible, the ship should only discharge the minimum essential amount of ballast water in accordance with the member country's contingency strategies
• Thermal methods, filtration, disinfections including ultraviolet light may be used to treat the ballast water

Safety Precautions when ships engage in ballast water exchange at sea
• Avoidance of over and under-pressurization of ballast tanks
• Free surface effects on stability and sloshing loads in tanks that may be slack at any one time
• Admissible weather condition and freezing temperature
• Weather routing in areas seasonably affected by cyclones, typhoons, hurricanes or heavy icing conditions
• Maintenance of adequate intact stability in accordance with an approved trim and stability manual
• Permissible seagoing strength limits of shear forces and bending moments
• Torsion forces where relevant
• Minimum/maximum forward and aft drafts
• Wave induced hull vibration
• Contingency procedures for situation which may affect the ballast water exchange, including deteriorating weather conditions, pump failure, lost of power, etc.
• Monitoring and controlling the amount of ballast water
• Adequate training and familiarization of ballast water exchange

In the United States, the Code of Federal Regulations (CFR) Title 33, Subpart D - Sections 151.2000 thru 151.2065 regulate all vessels equipped with ballast tanks that operate in the U.S. waters and are bound for the U.S. ports. If your voyage is less than 24 hours, you must report before departing your port or place of departure. If your voyage exceeds 24 hours, you must report at least 24 hours before arrival at your port or place of destination.

All required information is to be sent to the National Ballast Information Clearinghouse (NBIC) using only one of the following means:


1. Internet at: http://invasions.si.edu/NBIC/bwform.html;
2. E-mail to NBIC@BALLASTREPORT.ORG;
3. Fax to 301–261–4319; or
4. Mail to U.S. Coast Guard, c/o SERC (Smithsonian Environmental Research Center), P.O. Box 28, Edgewater, MD 21037–0028.

The USCG may take samples of ballast water and sediment, examine documents, and make other appropriate inquiries to assess the compliance of any vessel subject to this subpart. The master of a vessel shall make available to the USCG the required records. Because of the safety concerns contained in §151.2030, will not be prohibited from the discharge of ballast water in areas other than the Great Lakes and the Hudson River. However, the vessel must discharge only that amount of ballast water operationally necessary to ensure the safety of the vessels for cargo operations and make ballast water records available to the local Captain of the Port upon request.