Every year, tens of thousands of ships dock in 26 states to unload goodies from other countries. In a process called ballast exchange, they release 48 million gallons a day of fresh, brackish, or salt water they sucked in at another port to stabilize the vessel for its perilous transoceanic journey.

Not all the 3,000 (or so) plant and animal species that're sucked in with this water survive the trip or can live here, but many do. Zebra mussels (from Russia) clog Great Lakes intake pipes. Snakehead fish (from Africa and Asia) gobble resources in our lakes and rivers, but at least we in turn can eat them.

State requirements for managing ballast water vary, so for more than 20 years two federal agencies and both houses of Congress have tried to reconcile these into a single coherent standard.

The U.S. Coast Guard leads the effort. Like all federal entities charged with devising a one-size-fits-all program, it wants to get a handle on the problem. Ship owners are supposed to submit basic information (like how, if at all, their vessels treat this particular form of water pollution) for a National Ballast Survey that was mandated in 1996, but usually don't. Same goes for ballast water management plans and reporting.

Northwest Environmental Advocates of Portland, Ore., is attacking the problem through another federal agency. Three times since 1999, the nonprofit has sued to get U.S. EPA to require a National Pollutant Discharge Elimination System (NPDES) permit for ship discharges under the Clean Water Act. Each time, the organization gets a little closer to achieving its goal.

No single treatment approach removes every single organism from ballast water, so everyone's arguing over methodology. Environmentalists distrust biocides while engineers weigh heat versus filtration. Shipping companies don't want to spend the money on retrofitting or training employees on new equipment when they don't know what standards they're shooting for. Technology developers don't want to invest in R&D if there's not going to be a market for their products and services.

This month could bring a breakthrough, though. According to Water & Wastewater Equipment Manufacturers Association President Dawn Kristof Champney, EPA's expected to release a court-ordered proposed regulation. The Coast Guard is preparing to issue its final rule, which is parked in the Department of Homeland Security awaiting final review by the Office of Management and Budget. Hopefully, one or both are based on soon-to-be-ratified International Maritime Organization standards. If so, everyone will finally know what's expected and what their deadlines are.

Now, the Asian carp is an exception to this discussion. We brought that one on ourselves. To learn how, read “Fish out of Water” in the Oct. 25, 2010, edition of The New Yorker magazine. I promise you'll laugh.

- Stephanie Johnston,
Editor in Chief

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