(CN) - A federal appeals court in Cincinnati upheld a Michigan law regulating how ships take in and discharge ballast water, saying the measures helped keep ships from spreading "aquatic nuisance species" such as the zebra mussel from port to port.
A coalition of shipping companies and port associations challenged the constitutionality of the Michigan Ballast Water Statute, which forces ship operators to pay for a permit to use Michigan's ports. The state Department of Environmental Quality issues permits only to ocean-bound vessels that won't discharge any ballast water or promise to do so using "environmentally sound technology and methods" meant to prevent non-native species from entering the water.
Ships take on ballast water to balance the vessel after unloading cargo. The ballast water taken in at one port and dumped at another can carry aquatic organisms that often thrive in their new environments in the absence of natural predators.
To obtain the required permits, ship operators must fill out a three-page application and pay a $75 application fee, plus a $150 annual fee.
Plaintiffs claimed these fees, and the statute that mandates them, violate the Commerce Clause, the 14th Amendment and provisions of the Michigan constitution.
The district court dismissed the claims, and the 6th Circuit affirmed.
"Michigan, for undisputedly legitimate reasons, has enacted legislation of a type expressly contemplated by Congress," Judge Kethledge wrote. "We have no basis to disrupt the result of those democratic processes."
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