The report, which was obtained through an access to information request, says the unidentified woman arrived through an employee entrance just before 8 p.m. Easter Monday and stayed in the mayor's office about 45 minutes.
At the time, "the mayor appeared to be intoxicated as he was slurring his words, red in the face and sweating profusely," the report reads.
Security video also obtained through access to information shows the mayor being brought to a car in the city hall parking garage by his councillor brother Doug Ford and another guard just before 10 p.m.
"The mayor can be seen stumbling around and even falling to the ground before being seated in the vehicle," the report says.
Doug Ford is seen getting into the driver's seat with his brother on the passenger side. The car leaves the parking garage a few minutes later, after first attempting to take the wrong exit.
The woman does not appear in the video.
Asked about the incident Friday, Doug Ford said he was "not too sure" what happened that night but that he and his brother are "looking at moving forward."
"Rob is doing great at his treatment centre and we look forward to him getting out on June 30," he said.
The mayor announced on April 30 he was seeking help for an alcohol problem, just as new allegations of substance abuse surfaced in several published reports.
The Toronto Star and the U.S. website Gawker first reported in May 2013 seeing a video that appeared to show the mayor smoking crack cocaine.
Months later, Ford admitted to trying the drug while in one of his "drunken stupors'' and to using drugs while in office.
That led council to strip him of most of his mayoral duties.
Though the mayor then publicly swore off alcohol, he was later forced to admit to drinking after another videotaped incident in which he used Jamaican swear words and slagged the city's chief of police.