Some Great Lakes governors are at odds with one another over a fight against a common enemy — aquatic invasive species.

According to the Milwaukee Journal Sentinel, New York has been asked to ease its ballast water regulations (set to take effect in August 2013) for ships on the Great Lakes. The governors of Indiana, Ohio and Wisconsin, along with the Canadian government, made the request.

Wisconsin is one of three Great Lakes states (along with Michigan and Minnesota) with a ballast water permitting program up and running. But New York’s rules would be the region’s most stringent, with discharge standards exceeding those of the International Maritime Organization.

At issue is the technological feasibility of implementing standards tougher than the IMO’s and the impact that New York’s rules could have on the shipping industry.

For years, Great Lakes states have been calling for a stronger federal response. Later this year, the U.S. Environmental Protection Agency will propose a new Vessel General Permit; also pending is the U.S. Coast Guard’s final rule for a ballast water discharge standard. Under the first phase of this proposed rule, the IMO standard would be used. Tougher federal rules would follow as ballast water treatment technologies, and the ability to test them, advance.