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December 21, 2010

MADISON - Wisconsin is proposing to change its requirements for oceangoing ships arriving in its Great Lakes waters. The change would set ballast water discharge standards to those required by the International Maritime Organization. The proposed change reflects the latest science about reducing the risk from invasive species carried in the ships' ballast water, state officials say.

The proposed modifications to a general permit issued by the Wisconsin Department of Natural Resources to large oceangoing commercial ships will be the subject of a public hearing January 26 in Superior.

Large commercial ships take on and release water to help balance the vessels as cargo is loaded on and off. Along with the water, plants, animals and pathogens are taken in and released as well. Ballast water is the primary way aquatic invasive species such as the zebra mussel, round goby and spiny water flea have been introduced into the Great Lakes over the last century.

Wisconsin issued a ballast water discharge general permit effective February 1, 2010, with a requirement to determine, by the end of 2010, if effective treatment systems would be available by the implementation date.

The department engaged the Ballast Water Collaborative, a group of experts from academia, government, the shipping industry, testing facilities, treatment vendors and nonprofit organizations in an unprecedented in-depth discussion and review of ballast water treatment technologies and the science available to measure their effectiveness. The collaborative concurred with the latest science and technology reports that treatment systems have not been approved to the level Wisconsin's standard required and cannot be measured to that level to prove the treatment effectiveness. The group concluded that technology does not yet exist to verify whether a treatment system can rid ballast water of organisms effectively enough to meet Wisconsin's standard. A feasibility report (pdf)) based on the findings is available on the DNR website. This standard is set at a level of 100 times the International Maritime Organization standard.

After considering the best science and technology now available, Wisconsin is proposing to set the discharge standard in the permit modification to the international standard. Under the proposal, Wisconsin would continue to require oceangoing ships to treat ballast water to reduce the remaining organisms to a level that meets the international numerical standard.

To provide added protection, Wisconsin is also proposing to continue requiring ships to flush their ballast tanks at sea. This ballast water exchange process is now required by the federal government but is likely to change when revised federal rules are final, according to Matt Frank, secretary of the Wisconsin Department of Natural Resources.

"We want to be confident that we're getting the highest level of protection possible, and right now that includes making sure ballast water exchange continues, even if the final federal rules drop that requirement," said Frank. "The latest research suggests that ballast water exchange, combined with the required international standard, may result in better protection for our Great Lakes and inland waters."

Breaking research shows that exchanging ballast water at sea can reduce, typically by 95 to 99 percent, the number of invasive species that have the greatest chance of surviving and causing trouble in freshwater bodies, according to Sarah Bailey, PhD, a research scientist for of Fisheries and Oceans Canada, and a member of the collaborative.

Earlier research raised questions about the effectiveness of ballast water exchange. Bailey's research is showing that when the exchange is done right, the plants, animals and pathogens are purged at sea as the ballast water is exchanged; organisms remaining in the tank are then subjected to the saltwater taken in, which kills and weakens many of them,

"We've been completing analysis of flushing and we're finding such exchange is much more protective of freshwater ports than marine ports," said Bailey. "This idea of combining exchange with treatment may be a more meaningful increase in protection because you're now addressing two of the three factors necessary for a successful invasion, not just one."

The three factors are: how many of a particular species are released over time; whether environmental conditions (including salinity and temperature) are hospitable to a species; and whether the food chain is conducive to the survival and growth of a species.

In issuing its general permit, Wisconsin joined Minnesota, Michigan and New York in regulating large oceangoing ships entering Great Lakes waters to provide greater protection than provided by federal permit requirements. After more than a decade the federal government is still working on developing ballast water regulations.

Meanwhile, Wisconsin and other Great Lakes states, the federal government and the shipping industry jointly support the Great Ships Initiative, a research effort designed to find the most cost-effective treatment technology for freshwater shipping on the Great Lakes. It is expected that these research efforts will lead to better and quicker protection of the Great Lakes from aquatic invasive species.

Certain Wisconsin requirements for handling ballast tank sediment, seawater, and other substances took effect on February 1, 2010, and applied both to oceangoing ships and to the ships that travel only within the Great Lakes. Other requirements will phase in over time, specifically the numerical treatment standard that would apply only to oceangoing ships. New ships must meet the requirement in 2012 and existing ships in 2014. These implementation dates will remain effective in the proposed permit modification.

"If proposed changes to the permit requirements are made," Frank noted, "Wisconsin still has one of the most protective ballast water permits in the Great Lakes."

FOR MORE INFORMATION CONTACT: Susan Sylvester, DNR - (608) 266-1099 or Theresa Nichols, Fisheries and Oceans Canada - (204) 983-0600

Last Revised: Tuesday, December 21, 2010

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