Sometimes journalists think like economists.
Close the Seaway until oceangoing ships prove they won't continue to bring in strange new species in their ballast waters.
This doesn't necessarily mean closing Great Lakes ports to international cargoes. Those cargoes could be transferred from oceangoing ships to lake freighters or they could be placed on trains to finish their journeys. Yes, that would cost a little more than allowing oceangoing freighters free travel through the lakes. But given the cost that more invasive species will add, the price is worth it.
Most of the Lakes traffic is bulk cargo from lake port to lake port in any event, and the biggest ore carriers are too large for the Welland Canal.
Preliminary results from a federally funded study under way at the University of Notre Dame estimate that the economic loss tied directly to 57 exotic species scientists believe were delivered to the lakes by overseas vessels is about $300 million a year. And there are a lot more than 57 invasive species in the lakes now.
On the other side is the economic benefit of the seaway: about $55 million a year in terms of transportation savings, according to a 2005 Joyce Foundation-funded analysis of cargo flows on the Great Lakes. In a strict cost-benefit analysis, the seaway loses, big time.