TRAVERSE CITY, Mich. (AP) — A plan gaining support in Congress and backed by the cargo shipping industry would establish a nationwide policy for dumping ballast water into U.S. waterways that environmental groups say would open the door to more invasive species like zebra and quagga mussels, which have wreaked economic havoc from the Great Lakes to the West Coast.
The proposal was tucked into a $602 billion defense bill that the House passed last week, the latest twist in a longstanding struggle over how to handle water that ships carry in huge tanks during overseas voyages. Ballast provides stability in rough seas but harbors fish, plants and even viruses, which find new homes when vessels discharge the water in distant ports. Some multiply rapidly, out-compete native species for food and spread disease.
The debate focuses on how extensively ship operators should be required to treat ballast water to kill as many organisms as possible before the water is released.
Rep. Duncan Hunter, a California Republican who sponsored the House provision, said it's intended to simplify a confusing patchwork of state and federal ballast regulations that is burdensome to shippers and hampers interstate commerce.
"There has to be one single federal rule that everybody's required to go by," Hunter told The Associated Press by phone.
Environmental groups fighting for tougher treatment standards say Hunter's amendment would be a significant step backward. It would exempt ballast water discharges from regulation under the federal Clean Water Act, stripping the Environmental Protection Agency of power to set and enforce standards and leaving the Coast Guard, which currently shares those responsibilities, solely in charge.
"The Clean Water Act is the nation's only comprehensive law that can combat an environmental plague of aquatic invasive species that costs the U.S. economy billions of dollars and touches every single state in the union with its destructive powers," said Nina Bell, executive director of Northwest Environmental Advocates in Portland, Oregon.
In a statement, the White House said the Hunter amendment "undermines the ability to fight the spread of invasive species" and would "irreparably hinder the successful prosecution of unlawful discharges."
The Senate is expected to vote next month on its own defense bill. If the ballast water provision is not added, it will be among issues the two chambers will negotiate to produce a final version.
Critics contend the issue should be considered separately but was attached to an essential military bill to shield it from a presidential veto. But supporters say the annual defense measure routinely includes provisions dealing with the maritime industry because it's important to national security.
The EPA in 2013 required vessel operators to limit the number of live organisms in ballast water, based on international standards adopted by the Coast Guard the previous year. It also required oceangoing vessels to exchange their ballast water at sea, or rinse the tanks with saltwater if empty to kill freshwater creatures that may lurk inside.
A federal appeals court ordered the EPA last October to toughen the rules, saying treatment methods such as filtration, ultraviolet light and chlorine application could further reduce the number of surviving organisms. That order will be nullified if Hunter's amendment is enacted, environmentalists say.
Hunter said his provision is intended to set standards that match the best available technology for ballast treatment and could be strengthened as methods improve.
But Neil Kagan, attorney for the National Wildlife Federation, said the measure provides no financial incentive for the industry to do better.
"Ships could continue to discharge using the current technology forever," he said.
By prohibiting states from imposing stronger requirements, the measure would block them from protecting sensitive waters such as the Great Lakes, where quagga mussels and other invaders have upended ecosystems and caused untold economic damages, Kagan said.
Great Lakes shipping and ports organizations endorsed the Hunter amendment, saying it would give existing federal standards more time to work.
The provision "integrates best available technologies, best management practices and strict oversight to set a national approach to the prevention and control" of invasive species in ballast water, they said.
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