Proponents of an initiative aiming to promote use of buildings in Downtown Berkeley for public benefit announced Tuesday that they had gathered enough signatures to put the plan on the November ballot.

The Green Downtown and Public Commons Initiative would require that historic buildings be used for community benefits instead of commercial purposes. Additionally, the initiative would limit the height of buildings in the Civic Center area, which includes the post office, Old City Hall and Berkeley High School, to 50 feet and the surrounding Downtown area to 60 feet.

Under this initiative, developers who wish to exceed these height restrictions must follow a set of rules stipulating that the buildings are environmentally friendly and made for public benefit.

“The idea is to rezone properties so they can be used for civic, cultural, educational or other community services, which is consistent with what these buildings were built for and have been used for over the past 100 years,” said Councilmember Jesse Arreguin.

According to Arreguin, the initiative will help provide the “force of law” necessary to implement the goals of Measure R, a city zoning initiative approved by voters in 2010 that he said did not go far enough to promote the use of Downtown buildings for the public benefit.

Proponents of the initiative also hope this measure will delay the sale of the post office, arguing that it will be more difficult to sell if it cannot be used for commercial purposes.

“The post office, having been used for public benefit for so long, should be kept for public purposes,” said Greg Jan from the Green Party of Alameda County.

Opponents of the initiative, however, believe it imposes too many restrictions and would drastically hurt city efforts to revitalize the Downtown area.

“There are so many poison pills in it that when you take it cumulatively, then there isn’t a project that makes economic sense — that a developer will find feasible,” said Councilmember Laurie Capitelli.

Capitelli added that because the Berkeley post office and other old buildings are on the National Register of Historic Places, they are not at risk of being demolished.

Arreguin, however, said the initiative is about more than just preserving historic buildings, arguing that preserving what they are used for is just as important.

The initiative will also provide jobs and create diverse housing opportunities for low-income individuals, Arreguin said.

“We shouldn’t do our community planning around how to maximize developer profits,” Arreguin said. “It’s all about what the community needs.”

The city registrar has 30 days to approve the signatures supporting the initiative. If about 2,600 votes are verified, the City Council must vote on whether to immediately adopt the ordinance or to put the measure before Berkeley voters in November.