USCG’s Ballast Water Treatment
The Coast Guard is responsible for the U.S. effort to prevent the introduction and spread of aquatic nuisance species (ANS) through ballast water. To maintain their stability and safety or to maximize propulsion efficiency, during normal ballasting operations, ships fill their tanks with water containing living organisms. When discharged, the organisms in the ballast water are introduced into new habitats. These non-indigenous species may become established in the new environment and become aquatic nuisances.
ANS cause significant adverse environmental and economic impacts to the U.S. marine coastal and Great Lakes regions. For example, the management of zebra mussels near the Great Lakes has cost the U.S. economy millions of dollars annually. ANS can disrupt the food chain and reproductive success of native species. Once established, ANS are extremely difficult to remove. Prevention is a better and less expensive approach to protecting U.S. waters.
The Coast Guard proposed a standard for ballast water discharge applicable to vessels operating in U.S. waters and also intends to approve ballast water treatment systems (BWTS) for routine shipboard use. The Coast Guard partnered with the Environmental Protection Agency to develop a shore-based protocol for testing BWTS and establish shore-based test facilities. The Coast Guard is evaluating how facility differences can affect test results and developing methods to automate biological analysis. Automated analysis coupled with strong protocols will lead to standardization of test procedures. While many challenges remain, the ultimate outcome of this effort will provide a means for vessels to routinely treat ballast water and minimize the introduction of ANS.
For more information, visit www.uscg.mil.