CHICAGO -- The Chicago Park District has signed off on a 99-year lease for filmmaker George Lucas' proposed museum along Lake Michigan.

Park district officials voted unanimously Wednesday to approve the $10 lease on the lakefront property for the non-profit Lucas Museum of Narrative Art. The lease still has to be approved by the city's Department of Zoning and its Plan Commission.

Non-profit group Friends of the Parks is suing the Chicago Park District to prevent the museum from being built south of Soldier Field.

Current plans for the $400 million project call for a 300,000-square-foot structure with nearly 5 acres of green space.

Construction could begin as early as the spring and the museum could be operating by 2019 or 2020.