For nearly a year, authorities have been unable to identify a slight woman whose body was pulled from the Allegheny River near Fox Chapel Yacht Club.

	This illustration, prepared by police artists, depicts an unidentified woman whose body was found in the Allegheny River near O'Hara and the Fox Chapel Yacht Club.

The woman's badly decomposed body was found Oct. 24, wrapped in a blue blanket bound with duct tape and with a plastic grocery bag over her head. She was wearing a long-sleeved white blouse, blue jeans, white socks, white underwear and black slippers.

Dr. Cyril Wecht, the Allegheny County coroner, said yesterday that the woman died of a drug overdose, probably a heroin overdose, and that she also had phenobarbital, a sedative, in her system.

At a news conference, he released a picture, prepared by police artists using measurements and photos provided by the coroner's office, of what the woman may have looked like.

Authorities decided to "bring this to the public once again," Wecht said, in hopes of producing a break in the case.

The coroner's office and Allegheny County police have made extensive efforts to identify the woman, using fingerprints, seeking information from Crime Stoppers and following up on leads. They even checked water flow patterns in the Allegheny River to assess how far the body could have traveled.

But so far, who she is remains a mystery.

The case is rare in Allegheny County but not unique. The coroner's office is trying to identify three other adults, all women, among hundreds of cases spanning more than a decade.

On Oct. 3, 2000, a woman's mummified remains were found in an abandoned railroad tunnel in Homestead. A stainless steel crown on one of her teeth resembled those made in Eastern Europe.

On June 28, 1999, the skeletal remains of a black woman, about 18 to 20 years old, 5 feet 7 inches tall and 120 pounds, were found in the cellar of a vacant home in the 600 block of North Avenue in Wilkinsburg. Police said she had been strangled six months to a year earlier.

On June 19, 1997, an elderly black woman was found in a sleeping bag behind a Ponderosa restaurant on Route 65 in Avalon.

Also unsolved is the case of a newborn, with its umbilical cord attached, found floating in the Ohio River off Neville Island on April 11, 1999, Allegheny County police said.

Chief Deputy Coroner Joseph Dominick said infants pose special challenges to investigators unless witnesses come forward, in part because dental records and fingerprints are unlikely to provide clues.

None of the women carried identifying information, Dominick said. And no one has come forward who could identify them.

The situation is unusual for the coroner's office, which handles about 8,500 cases annually, conducting autopsies in about 1,200 of them.

Usually, the identity of the deceased can be confirmed within a few days, Dominick said, often through a picture ID or help from family members or friends.

In many cases, fingerprints are taken or an expert is called in to determine if the deceased can be identified through dental records.

But fingerprints don't help if they are not on file, or if the remains are too deteriorated to obtain them. While authorities were able to lift prints from the woman found near the yacht club, they did not match any in FBI records, Dominick said.

The coroner's office also considered about a dozen people reported missing, some of whom had dental records. But they did not match, either, he said.

DNA evidence could be gathered that could provide positive identification, but that information, too, has to be matched to an identified source, Dominick said.

Despite the obstacles, investigators do have a number of clues to the woman's identity.

They have determined she was about 5 feet 3 inches tall and 97 pounds, in her late 20s to early 40s, with medium-length brown or blond hair and brown eyes.

Wecht said the body showed no signs of beating or other trauma. But the woman's gall bladder had been removed and she had several surgical scars on her abdomen and a scar behind her right ear.

A check with the Army Corps of Engineers determined that the body could have traveled past locks or dams. It could have been dumped upstream, possibly as far away as New York, Wecht said. Dominick said the body was likely in the river at least a week.

Wecht said he remains surprised when no one comes forward to provide identification.

"It's kind of hard to believe that a young woman like this wouldn't have been reported missing."