SAN FRANCISCO (CBS SF) — A proposal to establish citywide park closure hours in San Francisco came one step closer to approval Monday when it was passed by a Board of Supervisors committee.

The legislation, authored by Supervisor Scott Wiener, would establish closure hours of midnight to 5 a.m. at most parks around the city, with exemptions for highly traveled plazas like Union Square as well as streets and sidewalks that go through parks.

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Wiener, speaking at a hearing of the board’s land use and economic development committee Monday afternoon, said the proposal is an attempt to combat vandalism and illegal dumping in parks.

Those problems cost San Francisco more than $900,000 annually to clean up, according to the city’s Recreation and Park Department.

“I believe this legislation is long overdue and provides us with one more tool for protecting our parks,” Wiener said.

Violators would face a fine of up to $100 for a first offense, with escalating fines and a possible misdemeanor conviction for subsequent offenses, he said.

Rec and Park general manager Phil Ginsburg said department employees often arrive to work in the morning to find “destroyed toilets, kitchen sinks left out in the parks, sports fields driven over in the middle of the night,” among other damage.

“It’s very demoralizing,” he said.

Ginsburg says he speaks to officials at parks departments in other major cities and “when they hear we don’t have codified hours, they are truly amazed.”

San Francisco is the largest city in the country without enforceable park closure hours, according to Wiener’s office.

However, opponents of the proposal said it would primarily affect homeless people who sleep in the parks overnight.

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Jennifer Friedenbach, executive director of the Coalition on Homelessness, said the legislation would be displacing “very vulnerable people who are currently residing in these parks.”

She said, “These folks are committing no crime except not having a place to live.”

“You’re being targeted because you’re too poor to be in a city that’s fast becoming a park and playground for the wealthy,” said Tom Temprano from the Harvey Milk LGBT Democratic Club, which opposes the legislation.

Wiener said the city does have to create affordable housing and shelter space for low-income and homeless people but said vandalism and illegal dumping is also a serious issue.

“There’s no magic bullet,” he said.

The committee voted 2-1 to send the legislation to the full board, with Supervisor Jane Kim providing the lone dissenting vote.

“I feel very torn about this legislation,” Kim said.

“This type of behavior is unacceptable,” she said of the vandalism and illegal dumping, but added, “I don’t want people to go to jail because they can’t pay the fines.”

The legislation will come in front of the full board at its Oct. 29 meeting.

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