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Ballast Water

Ballast water discharge

Ballast water is one of the major pathways for the introduction of nonindigenous marine species. Ballast water is fresh or saltwater held in the ballast tanks and cargo holds of ships. It is used to provide stability and maneuverability during a voyage when ships are not carrying cargo, not carrying heavy enough cargo, or when more stability is required due to rough seas. Ballast water may also be used to add weight so that a ship sinks low enough in the water to pass under bridges and other structures.

Usually ballast water is pumped into ballast tanks when a ship has delivered cargo to a port and is departing with less cargo or no cargo. Ballast water is then transported and released at the next port-of-call where the ship picks up more cargo. If a ship is receiving or delivering cargo to a number of ports, it may release or take on a portion of ballast water at each port. In such cases, the shipís ballast water contains a mix of waters from multiple ports.

The release of ballast water may introduce non-native organisms into the port of discharge. These introduced species, or bioinvaders, are also referred to as exotic species, alien species and nonindigenous species. (Source: Massachusetts Institute of Technology Sea Grant - Ballast Water)


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Spotlights

Selected Resources

The section below contains selected highly relevant resources for this subject, organized by source. To view all related content for this subject, click on "View all resources for subject" in the top left of this page.

Partnership

Pacific States Marine Fisheries Commission.
GloBallast Partnerships Programme.
Building Partnerships to Assist Developing Countries to Reduce the Transfer of Harmful Aquatic Organisms in Ships’ Ballast Water, simply referred to as GloBallast Partnerships (GBP), was initiated in late 2007 and is intended to build on the progress made in the original project. This was initially planned as a five-year project, from October 2007 to October 2012, but was extended until June 2017.

Federal Government

Library of Congress. Congressional Research Service.
Congressional Research Service Report RL32344.
U.S. Government Printing Office. Federal Depository Library Program Electronic Collection Archive.
Compiled and Edited by: Gregory Ruiz and David Reid, NOAA Technical Memorandum GLERL-142.
See also: GLERL Technical Reports for more reports

International Government

Transport Canada.
European Maritime Safety Agency.

State and Local Government

Hawaii Department of Land and Natural Resources. Division of Aquatic Resources.
New York Department of Environmental Conservation.
Reprinted and provided by: Clear Waters Magazine (Fall 2011, Vol. 41, No. 3)
Washington Department of Fish and Wildlife.

Michigan Department of Environmental Quality.

California State Lands Commission.
California Department of Fish and Wildlife. Office of Spill Prevention and Response.

Michigan Department of Environmental Quality.

Minnesota Pollution Control Agency.

Academic

Massachusetts Institute of Technology Sea Grant. Center for Coastal Resources.
University of California - Davis.

Professional

Prince William Sound Regional Citizens' Advisory Council.
National Research Council. Committee on Ships' Ballast Operations.