Mayor Ed Lee signed off on the $2 billion deal in July, clearing the way for California Pacific Medical Center' s new hospital at Van Ness and Geary.
Construction is expected to begin next June. The new Cathedral Hill Medical Center will have more than 300 beds and offers another centrally located emergency center.
The deal also calls for the remodeling of Saint Luke's Hospital in the Mission District.
Both projects are due to be completed in 2019.