HALIFAX -- A review has been ordered into the Halifax police investigation of the death of a blind woman who was found lying beneath a city bridge almost four years ago.

Holly Bartlett was discovered unconscious under the McKay Bridge in Halifax early on March 27, 2010, and died in hospital the following day.

The police investigation at the time concluded the 31-year-old woman had become disoriented after leaving a taxi in the early morning hours and fell 10 metres off a concrete abutment that anchored two thick cables at the suspension bridge across Halifax harbour. It is surrounded by a chain-link fence.

Last year, Bartlett's family contacted the chief of police to say they had concerns about the investigation.

Chief Jean-Michel Blais said in an interview Monday that he visited the site, talked to the family and arranged interviews with them.

He said he asked for investigators from the Quebec City to look into the case because of the continuing concerns of the family and his own desire to know if anything could have been done differently.

It remains unclear how Bartlett managed to get out of the taxi, walk down a pathway and pass through a hole in a fence before reaching the abutment.

"What's unusual is the distance that was travelled by Ms. Bartlett and the fact she managed to get into that area," Blais said.

He said Bartlett appeared to have travelled almost 300 metres between the curb and the place where she was found.

Toxicology reports concluded she had a blood alcohol level of 0.09, or 90 milligrams of alcohol in 100 millilitres of blood, Blais said. "If you were to extrapolate backwards, her blood alcohol the night before was 0.2, which is over twice the legal limit to be able to drive a vehicle," he added.

Marion Bartlett said the family is pleased and surprised that her daughter's case is being reviewed.

"We're confident now that after four years, this is a step in the right direction," she said in an interview.

Blais said Halifax police believe the case was an unfortunate accident, but he remains open to any fresh evidence.

"Perhaps we could have done something else in this investigation. That's fine, we will do that something else," he said.

He said police interviewed a taxi driver who dropped off Bartlett near her home.

"We have no evidence leading us to believe there was any foul play involved in this," he said.

"Yes, there was an interaction between the taxi driver who drove her to the entrance to the building, but there's nothing that leads us to believe he was involved in the accident leading to her demise."

Blais said he asked Quebec City's police department do the review because they operate in a similar-sized city and are the closest with a large major crimes unit.

He said he expects the review and possible recommendations to take about two months to complete.