By LAUREN GIBBONS
Capital News Service
LANSING — The underbellies of cargo ships and their ballast water have become a battleground for environmentalists and shipping businesses throughout the Great Lakes. Michigan’s rigorous treatment standards for ballast water, which most large vessels use as a balancing mechanism when carrying heavy cargo, have caused friction between environmental and industrial interests as legislators consider a proposal that might keep invasive aquatic animals out of the lakes without crippling the state’s shipping industry. A bill sponsored by Sen. Mike Green, R-Mayville, would lessen the standards and allow ships to use ballast water exchange, a method of exchanging freshwater ballast for saltwater ballast without additional treatment. That change would match national and international requirements put in place by the U.S. Coast Guard and the International Maritime Organization. Supporters of the bill argue that looser standards would help rebuild the state’s shipping industry and allow more seafaring vessels to export Michigan cargo, but environmental activists and some senators are concerned the lowered standards will make the Great Lakes more susceptible to invasive animals.