Get ships into shape
Making treatment mandatory would protect fragile great lakes
By Craig Saunders
For decades, Lake Erie was the toxic dumping ground of the American industrial heartland. Public pressure in the 1970s led to a multimillion dollar cleanup, and today, Lake Erie is considered a miracle: The Lake That Lived. But while Erie may be winning its battle with pollution, it's still under attack from another threat — invasive species. Arriving at a rate of about one every eight months and facing few if any predators, foreign creatures challenge native species for survival, and threaten the lake's ecology and the many economies it supports.
There is a solution. Since many invasive species arrive in the ballast tanks of the 450 to 550 saltwater freighters that enter the Great Lakes each year, enacting laws that would require any visiting ship to treat its ballast water would virtually eliminate the risk of foreign animals being pumped out.
Ships use ballast water to balance the weight of their cargo. As this weight changes, the water, and anything living in it, is pumped out. This practice is believed to have introduced zebra mussels, originally from West Asia, to the Great Lakes in the '80s. Current regulations compel ships to flush their ballast water in the open ocean, but residue and organisms can still remain. Systems that kill off anything living in the ballast tanks have existed for years, but at $600,000 to $36 million per ship for a treatment system, the shipping industry has been reluctant to buy these technologies.
But given the costs of invasive species, it's time for the Canadian and U.S. governments to forceship owners to make the investment. Zebra mussels alone have caused billions of dollars in damages, while a new invader, the Caspian Sea- originating round goby, is threatening the lake's $200 million fishing industry. That fish, along with the infamous zebra mussel (now largely replaced by its hardier cousin, the quagga mussel), has also been linked to botulism outbreaks killing off area seabirds.
While all the Great Lakes are being invaded by foreign species, Lake Erie, with its shallow, warm waters, is the most inviting and therefore the most at risk to these stowaways. Unless swift, decisive action by Canadian and U.S. governments is taken, all the hard work that's gone into saving Lake Erie might be for nothing.