Susanne Brito, 48, a mother of three from Uxbridge, Ont., died in hospital the following Tuesday.
Linda is the wife of celebrity businessman Kevin O'Leary, who was a passenger in the couple's boat at the time of the incident.
According to TMZ, the Ontario Provincial Police (OPP) obtained five videos from cameras in the area and concluded Linda was driving 17 miles per hour around 11:30 p.m., which police say was not a safe speed.
Also charged is Richard Ruh, 57, of Orchard Park, New York, with failing to exhibit navigation lights.
Linda O'Leary is scheduled to appear in court on October 29.
We're told Linda is going to "vigorously fight the charge".
He said last month that his wife was at the wheel when they were "in a tragic collision with another watercraft".
Linda and Kevin O'Leary are seen in this
Three other people suffered injuries as well; all were treated and released from the hospital.
Ruh did not immediately respond to a request for comment.
After the accident occurred in August, Kevin told ET in a statement that he was cooperating with authorities. O'Leary is cooperating with law enforcement in their investigation into this tragedy. "O'Leary under the shipping regulations in circumstances where the person has always been a cautious, and certainly experienced boater, came in a collision with an unlit craft on a dark and moonless night on Lake Joseph". "My thoughts are with all the families affected".
O'Leary, a businessman and former Dragons' Den star on CBC, made a bid for the federal Conservative leadership race before dropping out in 2017.
Our sources say the OPP obtained 5 videos from cameras trained on the lake and they concluded she was driving 17 miles per hour at around 11:30 PM. which police say was not a safe speed.
O'Leary now stars in the ABC show "Shark Tank".