NEW YORK, JAN. 21 -- More than 703 tons of Bronx household trash were awash after a garbage barge sank today in the polluted East River.

Trash barge No. 109, one of more than 20 in the city's sanitation fleet that make daily runs to a Staten Island landfill, collided with an empty city sewage tanker in the early morning fog and sank about 7 a.m. Three other garbage barges in the fleet sustained minimal or no damage.

Although the river is usually too dirty for fishing and swimming and is not a source of drinking water, the city's Department of Sanitation set up an elaborate rescue operation -- using mechanical diggers, skimmer boats and crane lifts -- to retrieve what the Bronx had discarded.

Department spokesman Jim Hart said salvagers put a containment boom in place to prevent the garbage from floating away.

Hart thinks the drifting trash is "headed for Long Island. I just hope it doesn't wash up on the Jersey shore," he said, recalling the legal warfare that erupted last summer when New Jersey blamed New York for solid wastes that washed up on its beaches.

The Environmental Protection Agency's local office dispatched inspectors to survey the situation from a helicopter and reported that close to 95 percent of the garbage has been contained, spokeswoman Kim Helper said.

Petty Officer Brad Terrill of the U.S. Coast Guard, which is investigating the collision, reassured all sludge boat captains sailing the East River that "neither the barge nor the garbage pose any hazard to navigation."

The barge, which will be refloated, was part of a raft of four barges being pushed by a tug. Visibility was one-quarter to one-half mile but worse in patches of fog, Coast Guard officials said.

There have been four accidents involving garbage barges in the last 10 years, Hart said.