Early this summer, while Great Lakes residents and tourists return to beaches to swim and open waters to boat and fish, something else is happening in a far less scenic part of the region-meeting rooms in six cities. Sitting behind conference tables and standing at microphones, officials and citizens will be exchanging views on the future of Great Lakes shipping. Included will be debate over one option the U.S. Army Corps of Engineers wants to investigate: a plan to manipulate the ecosystem to introduce the world's largest ships at an outrageous cost to taxpayers.

Why is this even being considered?

To understand, we have to consider the history of human attitudes toward the Great Lakes since the founding of the United States and Canada. While praising the Lakes for their beauty, we have never been able to resist the temptation to believe they can be improved and bent to our will.

Responding to overfishing in the 1800s, early manipulators of the Lakes introduced a variety of exotic fish that have since colonized the Lakes. Industrial tycoons proposed diverting all the waters of Niagara Falls to power all of North America, wrecked scenic sand dunes to build factories, and poured their toxins into harbor muds that are still contaminated 100 years later. Shipping proponents dug canals that allowed the parasitic sea lamprey to enter the four upper Lakes and nearly wipe out the fishery. Polluters used the "assimilative capacity" of the Lakes to dilute their wastes, making them nearly unfit for recreational uses like swimming and fishing.

For too much of our history, governments and big business have regarded the Great Lakes as a storehouse to be ransacked, reconstructed and "enhanced."

That all changed in the 1970s. As citizen outrage about pollution peaked, a few visionaries proposed a new way of living among the Lakes. Called the "ecosystem approach," this policy envisioned considering the health of the system in totality, rather than assuming humankind could be healthy even when the Lakes were sick. Most importantly, the ecosystem approach urged caution and humility in altering the complicated Basin that contains 18% of the world's surface fresh water.

The results of this approach are tangible. Levels of phosphorus pollution are down more than 70% since the 1970s. Chemicals like DDT and PCB have declined by over 90%. We can use our beaches more often and, within limits imposed by contaminants like mercury, enjoy the bounty provided by the vast fish stocks of the Lakes.

But the ecosystem approach hasn't yet been tried in one area of Great Lakes policy-the control of exotic species. In 1981, Canadian researchers predicted that a non-native species, the zebra mussel, had potential to reach the Great Lakes through ships carrying ballast water, survive and upset the Lakes' food web. What did the U.S. and Canada do with this information? They shelved the study because it would have threatened the interests of companies with oceangoing vessels. Five years later, the zebra mussel appeared, and taxpayers are paying $1 billion a year to control it.

Now the U.S. Army Corps of Engineers and Transport Canada are holding public meetings on whether or not maintaining the current St. Lawrence Seaway system until the year 2060 is desirable. But the backdrop for these meetings is a favorable study the Corps finished in 2002 that supported as one option, at a potential public cost of $10 to $20 billion, allowing 1,000-foot ships with 35-foot drafts to operate through the Lakes. Although this proposal is technically on hold while this summer's meetings and a supplemental study go forward, the history of the Corps and other shipping proponents strongly suggests that the "Big Dig," as it's nicknamed, will be back on their drawing board.

Why is that bad? Well, for one thing, the shipping industry has successfully blocked legally-binding controls on the dumping in the Great Lakes of ballast water that contains invasive species like the zebra mussel, round goby and spiny waterflea. About every seven months, a new alien species enters the Lakes. The "Big Dig" would mean even more oceangoing vessels in the Lakes-and more invaders.

Worse, the proposal would destroy sensitive fish and wildlife habitat through the carving of islands, dredging of contaminated sediments and deepening of channels. It would also increase the speed of water flow out of the Great Lakes and permanently lower Lakes levels.

In other words, the shipping industry and its friends in the Corps and Congress want to have their cake and eat it too. They want to escape binding ballast water controls and reap more profit at public expense through the manipulation of the Lakes.

That's why many environmental groups are now advocating, rather than expanding the Great Lakes navigation system, closing it down to oceangoing vessels by requiring the shifting of cargo from saltwater to freshwater vessels at a central point like Montreal. That would be consistent with the ecosystem approach-and deserves the support of Michigan citizens, top legislators and our governor. But a newspaper in Duluth, which covets the extra shipping profits, calls the idea "extreme."

What seems more extreme to you: blasting islands and dredging channels at a cost of $10 billion, while inviting more alien species to upset the Great Lakes, or shutting the door on them and protecting these waters we call home?