A public comment period has opened for Minnesota's new ballast water discharge permit for ships. The state will require permits for most of the ships calling on Minnesota ports like Duluth.
Eventually, ships will have to install technology intended to kill living creatures in the ballast water, but the MPCA's Paul Eger said that technology isn't ready just yet.
"There are a lot of things that can be done right now. For example, our permit includes some best management practices, so those will be in effect immediately, when the permit's issued. And then, one of the things that we want to see accomplished over time is the development and implementation of treatment technology on the ships, so there's certainly things that we can be doing right now," Eger said.
The permits will affect 300 or more ships. The MPCA says there are close to 60 unwanted organisms in Lake Superior believed brought into the lake aboard ship ballast water.
A comment period on the draft permit remains open until July 30.