Saving fish in troubled waters

A Michigan Technological University professor has developed a new water treatment that could help keep a deadly fish disease out of Lake Superior.

A Michigan Technological University professor has developed a new water treatment that could help keep a deadly fish disease out of Lake Superior in North America.

Prof David Hand of the civil and environmental engineering department at the university has devised a simple way to treat ballast water in vessels ranging from pleasure craft to ore boats.

His method is designed to kill the virus that causes viral hemorrhagic septicemia (VHS), an often-fatal disease that has been attacking fish populations in the lower Great Lakes.

Prof Hand's treatment is simple. The ballast water is disinfected with sodium hypochlorite - ordinary household bleach. Then it is treated with ascorbic acid, or vitamin C, which neutralises the bleach before the water is released into the lake.

With good initial results, Prof Hand has tested his method on the Ranger III, a National Park Service vessel that shuttles visitors and staff between the mainland and Isle Royale National Park.

In the next few weeks, the Great Ships Initiative will conduct independent laboratory tests on his system at the University of Wisconsin-Superior to help determine if it is safe, effective and inexpensive.

Other partners in the effort are the US National Park Service and the US Fish and Wildlife Service.

Since 2003, VHS it has caused massive declines in population among fish species, ranging from walleyes to salmon, in all of the Great Lakes except Superior.

If tests show that his system is as safe and effective as he believes, Prof Hand hopes to map a strategy to implement its use throughout the Great Lakes.

The Great Ships Initiative is a public-private collaborative that aims to halt the ship-driven spread of exotic species through the Great Lakes and the St Lawrence Seaway.

In addition to conducting research and development on possible ballast treatment systems, the Great Ships Initiative supports harbour monitoring and develops financial incentives to encourage ballast treatment and to protect the Great Lakes ecosystem.