SAN FRANCISCO (CBS SF)— As the San Francisco Museum of Modern Art prepares to close for nearly three years for a 225,000-square-foot expansion project, a groundbreaking ceremony was held Wednesday morning to celebrate the start of construction.

The ceremony, attended by Mayor Ed Lee and other city and museum officials, comes just before SFMOMA plans to close its doors at the end of the day on Sunday to make way for the expansion, which will include a new 10-story addition along the back of the current building at 151 Third St.

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The new building will feature a glass-walled gallery facing Howard Street that will allow passersby to see some of the museum’s artwork when it reopens in early 2016.

Museum officials also recently announced that they intend to offer free admission to those 18 years of age or younger at the renovated museum, and that the final four days this week before the museum closes will be free to everyone.

Museum director Neal Benezra said the expansion is necessary because “we had simply outgrown this building in a profound way.”

The mayor touted the expansion, saying it will bring even more visitors to San Francisco.

“This is what our city does, it celebrates culture. This is what draws so many people,” Lee said. “This is a gift that will keep on giving.”

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Supervisor Jane Kim, whose district includes the museum, thanked SFMOMA for its commitment to educational opportunities for children, especially given budget cuts to art programs at public schools.

Students from nearby Bessie Carmichael Elementary School assisted in the groundbreaking, at which confetti shot out of a cannon as museum and city officials dug shovels into the dirt.

Benezra called the expansion “the most exhilarating and exciting time in the history of this museum.”

During the closure, SFMOMA plans on staging various off-site exhibits, including one unveiled last week at Crissy Field that includes large sculptures by local artist Mark di Suvero.

Museum officials are still collecting money to fund the expansion. So far, they have raised about 90 percent of the $610 million needed for the project.

More information about SFMOMA and the expansion can be found on the museum’s website at

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