The report on April's Elements Music Festival also suggests an unsupervised entrance was the portal for illegal drugs into the venue at the city's Northlands complex.
It says the drugs were brought in through a DJs and promoters entrance not supervised by police or security, or were tossed over a fence into a smoking area.
It also says that over two nights, several patrons had to seek on-site medical help for life-threatening conditions.
Sgt. Nicole Chapdelaine of the city's Public Safety Compliance Team says that without prior emergency medical planning, the likelihood of someone dying from an overdose would have been extremely high.
The report, which will go to the city's executive committee next week, says one patron is still in intensive care and may need acute medical aid for the rest of their life.
City Coun. Dave Loken says despite all security efforts, there are still questions about how illegal drugs can be kept out of such events.
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