The Los Angeles County Museum of Art has published a final environmental impact report for the proposed $650-million rebuild of its Miracle Mile campus, detailing more changes to the project.

Since unveiling plans for its Peter Zumthor-designed makeover in 2013, LACMA's plan has evolved over several iterations. Originally depicted as an amorphous, black building inspired by the adjacent La Brea Tar Pits, the project underwent its most serious change in 2016, when LACMA announced its intent to bridge the structure over Wilshire Boulevard. A subsequent design change switched the proposed building's exterior to sand-colored concrete.

The project's latest iteration does not diverge significantly from its prior form, but does make adjustments to the Zumthor building's size and footprint. The most notable changes are a reduction in the square footage of the proposed building from approximately 390,000 to less than 350,000 square feet. Additionally, the removal of several planned galleries on the building's upper level will shorten its maximum height from 85 feet to 60 feet.

Other revisions to the design largely focused on its ground-level appearance, adding transparency to improve street activation across the site - particularly along Wilshire Boulevard. The amount of proposed open space that will be added to the campus - 2.5 acres - remains the same.

The revised LACMA project would also come with a significantly speedier construction timeline. While the previous design would have been built over an approximately 68-month period, the updated project could be constructed over approximately 51 months. This faster timeline is possible due to both the more modest scale of the project, as well as the ability to overlap more phases of the buildout.

An updated groundbreaking date has not been announced - the project's draft environmental impact report had estimated that work would begin in 2018.

LACMA is not the only Los Angeles area museum working on an eye-catching expansion. Just west of the LACMA campus at Wilshire and Fairfax Avenue, the Academy of Motion Picture Arts and Sciences continues with construction of its Renzo Piano-designed home - a $300-million facility that will inhabit a restored May Company department store and a new building in the shape of a glass-and-concrete sphere.

At Exposition Park, the Lucas Museum of Narrative Art is in the midst of construction of a $1-billion spaceship-like structure designed by MAD Architects.

The proposed LACMA rebuild has been the subject of controversy in the Los Angeles architecture world, as the Zumthor building would replace structures designed by notable mid-century architects William Pereira and Hardy Holzman Pfeiffer. Several Pereira-designed buildings are targeted for redevelopment in the coming years, including a portion of Times Mirror Square and the former headquarters of the Metropolitan Water District.