Orange County Dist. Attorney Tony Rackauckas, Joyful Child Foundation founder Erin Runnion and other advocates from victims' right groups were among those in attendance at the meeting.
Runnion spoke before the council about national statistics that show that the majority of sexual assaults go unreported to police.
"Surely you can agree that this is the least we can do as a community to protect our children from the few that we have caught," Runnion said of convicted sex offenders.
There were 44 registered sex offenders listed as living in Irvine as of June, according to a city staff report.
Adopting the ordinance is "common sense," said Councilman Jeffrey Lalloway, who first brought forward the ordinance as a discussion topic at the May 10 council meeting.
"We must always look for ways to increase the safety of the city's children," he continued.
Lalloway had pushed for a version of the ordinance which banned all registered sex offenders from entering parks. But a motion was made by Councilman Larry Agran to narrow the ordinance to ban just those offenders convicted of crimes against children.
A similar ordinance was adopted by the Orange County Board of Supervisors on April 5 in which limited "registered sex offenders' access to locations such as the regional and wilderness parks, nature preserves, recreational trails, historic sites, harbors, and beaches where children regularly gather," according to the ordinance.
Under the ordinance, registered sex offenders are banned from William R. Mason Regional Park, a 345-acre county-owned and maintained park on University Drive in Irvine, unless they get permission from the sheriff.
If the city ordinance is approved, registered sex offenders convicted of crimes against a minor would be banned from city-owned and maintained parks, which include the Orange County Great Park, 18 community parks and 37 neighborhood parks. However, like the county ordinance, registered offenders can apply for exemptions to enter parks in special cases.