Coast Guard sets ballast cleansing requirements

JOHN FLESHER AP Environmental Writer Published:

TRAVERSE CITY, Mich. (AP) -- The Coast Guard is requiring oceangoing ships to cleanse ballast water before dumping it in U.S. waters to protect the Great Lakes and ocean coastal areas from foreign species invasions.

A regulation announced Friday orders cargo vessel operators to install technology limiting the number of live organisms in ballast water. The limits follow international standards that the shipping industry says are achievable, but environmentalists say are too weak.

The regulation drops an earlier proposal to impose significantly tougher limits by 2016. Instead, the Coast Guard said it will do more research on whether stronger requirements are achievable.

Ballast water keeps ships stable in rough seas. Invasive species such as zebra and quagga mussels have hitched rides inside ballast tanks to U.S. waters, where they've caused billions of dollars in damages.