Ottawa police appear to be on the verge of laying charges in connection with a sexual assault in an Ottawa taxi over the weekend.

CBC News has learned a 55-year-old male driver is suspected of picking up a 20-year-old woman near the intersection of Bank Street and Hunt Club Road, taking her to an area near Walkley and McCarthy roads and sexually assaulting her inside the vehicle.

Using GPS data, cab models and information on the drivers, police and Blue Line taxi officials were able to narrow their search from around 1,000 taxis to about 50.

They then ordered that group of taxis to come to a garage where police were waiting to examine the cameras, which are required in every taxi by a city bylaw.

It was then they found the video footage they had been looking for, giving them reason to impound a taxi.

Footage gone after 5-7 days

Time had been increasingly against the police, since the city’s bylaw department says images are wiped from Ottawa’s taxi cameras after five to seven days.

The amount of time that had passed since Saturday meant the data was on the verge of being erased.

Hanif Patni, president of Coventry Connections, said the investigation was like a haystack with a thousand needles in it. (CBC)

The head of the company that owns Blue Line and provides tracking services to other major Ottawa taxi companies said tips from their drivers also helped with the search.

“It was only a matter of time. Our network of drivers wouldn't stand for someone getting away with something like this,” said Hanif Patni, president of Coventry Connections.

“What we first have to do is take this haystack with a thousand needles in it and try to figure out which ones we want to take a look at.”

No charges have been laid against the male suspect, who has been working for Blue Line for about a year.