Mayor Ed Lee signed legislation Thursday that allows the controversial development of the 152-acre Parkmerced site in The City’s southwest corner, according to spokeswoman Christine Falvey.

The controversy stems from concerns of existing Parkmerced tenants about their future housing. Many are worried they won’t be able to return to their rent-controlled apartments after the completion of the project.

The massive development of 5,700 new housing units was narrowly approved Tuesday by the Board of Supervisors.

“I want to commend all the members of the Board of Supervisors for thoughtfully considering these two sensible and smart urban development plans, and ultimately approving both projects for the working families and future of San Francisco,” Lee said in a recent statement.

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