The EPA says it won’t require permits for ships discharging ballast water despite complaints that the discharges are introducing invasive species into coastal waters.

The EPA, in a decision released in September, said the U.S. Coast Guard has jurisdiction over ships that discharge ballast water.

Right now, the Coast Guard requires ships to discharge ballast water before entering U.S. ports, but compliance is voluntary.

In 1999, the Pacific Environmental Advocacy Center and other environmental groups asked the EPA to regulate ballast water discharges under the Clean Water Act. But the EPA said ballast water is considered “discharge incidental to the normal operation of a vessel,” and therefore not subject to permits.

The EPA also said requiring permits would be impractical, because there are more than 78,000 commercial cargo ships and 110,000 commercial fishing ships docking in U.S. ports each year.

Environmental groups said that it is likely they will sue the EPA to attempt to persuade a judge to force the agency to use the Clean Water Act in the fight against invasive species.

“EPA has completely abdicated its responsibility,” Linda Sheehan, Pacific Region director of the Ocean Conservancy, a San Francisco-based environmental group, told Knight Ridder newspapers.

“Invasive species are like chemical pollutants that mate. Once they are here, they are here to stay. They cost hundreds of millions of dollars a year to keep in check, and environmentally, they push threatened and endangered species over the edge.”

Jon Brandt, a spokesman for U.S. Rep. Vernon Ehlers, R-MI, said that an update to the National Invasive Species Act now before Congress would give the EPA and the Coast Guard dual authority over ballast water.

A 2001 Bay Program report called for the federal government to regulate the handling of ballast water when it updated the act, and to significantly step up monitoring programs that look for foreign fish, worms, algae and other potential coastal water invaders.

After a ship unloads its cargo, it routinely sucks huge amounts of water into its hold as ballast to steady the vessel for its return voyage, usually releasing the water when it reaches its destination.

More than 3 billion gallons of ballast water are released into the Bay each year, as much or more than any bay in the nation.

Present federal law encourages vessels to exchange ballast water at sea before entering ports because organisms in high-salinity ocean water are less likely to survive when released into less salty coastal water.

The law also requires that ships report how they handled ballast water when they arrive in port.

But the Bay Program report indicates that only 22 percent of vessels actually made such a report when they arrived in the Chesapeake, and no penalty exists for failing to do so.