Diego Rivera Mural Awaits its New Home


By River Bradley

Collaborator to The Guardsman


Lifelike images of Diego Rivera’s “Pan American Unity” mural will be freely accessible 

thanks to a National Endowment for the Humanities grant, as stated by Cultural Heritage Imaging Founder and Director, Carla Schroer. 


Mural caretaker and City College alumnus Will Maynez said, “What we’re trying to do now is leave a … highly detailed record of the state of the mural at 80 years of age.”


Nov. 2020 marked 80 years since the mural’s first public showing. Cultural Heritage Imaging (CHI), a non-profit organization that develops digital tools to preserve cultural artifacts, received a six-month, $47,000 CARES Act grant to complete documentation of the mural before its temporary move to the San Francisco Museum of Modern Art (SFMOMA), according to Schroer. 


Originally painted for a world fair on Treasure Island in 1940 as the main attraction of the “Art in Action” exhibit, the 22-foot-high, 74-foot-long mural went into storage until City College 

gave it a permanent home in 1961. 

Photo courtesy of the December 11, 2017, SFMOMA Newsletter.

Diego Rivera said about this mural, “My mural will picture the fusion between the great 

past of the Latin American lands, as it is deeply rooted in the soil, and the highly mechanical 

developments of the United States.” 


In the second half of 2020, experts at CHI finished what they started in 2015. The new 

grant funded “additional imaging, digital public access to the images, and integration with 

recently acquired conservation data,” Schroer said. 


To document the mural, CHI used a technique called photogrammetry to “create a 3D 

digital surface that replicates surface shape and color” using archival quality photographs, 

Schroer said. They used a high resolution camera with two different lenses, a 50mm lens to 

capture the detail, and a 24mm lens to capture the geometry of the surface. 


The mural is a fresco, which means it was painted on wet plaster, Maynez explained. The surface of the plaster “actually has a lot of texture that follows the design of the mural,” Schroer said. In the summer of 2019, SFMOMA gathered a conservation team to assess the state of the mural in preparation for the move and preservation.


“The big surprise” was when CHI arrived in June 2020 to complete the photoimaging. “They said, ‘Oh my God it’s so much brighter,’ because the conservators cleaned the entire 

mural, revealing the vibrant colors underneath years of dust and grime,” Maynez said. 


According to Schroer instead of photographing the edges and a few other spots as planned, CHI reimaged the entire artwork with the 50mm lens to capture the revitalized artwork. 


Part of the conservation work was mapping “giornata lines.” Giornata is an Italian word that means “one day’s work,” referring to the amount of painting that is done in a single 

day on a fresco, Maynez said. “You can imagine it, the mural’s made up like a jigsaw puzzle, all these odd shaped pieces that are dove-tailed together.” 


Stanford Digital Library Systems, a group within the Stanford Libraries system, “will 

digitally house the mural finished data, and make it publicly accessible through their Mirador 

viewer,” Schroer said. Once complete, the work can be viewed in layers — from the surface to the plaster, including the giornata lines. 


SFMOMA planned the move for an anniversary celebration of Rivera’s work in San 

Francisco for October 2020. However, the COVID-19 pandemic has pushed the museum’s plans to Spring 2021.


University of Mexico’s (UNAM) graduate mechanical engineering department has done 

the majority of the engineering and analysis of the mural. They even built replica panels, as reported by Maynez. 


Maynez said the challenge of the move to SFMOMA is preserving the lobby wall in the Diego Rivera Theatre because it was “installed permanently without the understanding that 

it could last centuries, which would require a future move.” 


“Luckily, the team moving the mural is world-class, and is CCSF’s best-case opportunity to implement the required move,” Maynez said. 


While the move to SFMOMA is delayed, but definitely still scheduled, in November 2020 City College ended its work with the original Design Build Team or Design Build Entity (DBE) hired to complete the mural’s new home. 


According to Rosie Zepeda, City College’s director of media, governmental relations, and marketing, SFMOMA will keep it until Fall of 2022, when it will move to the newly-built Performing Arts & Education Center. 


Board Trustee and Board Facilities Committee Chair, John Rizzo, explained the former DBE 

costs were higher than market rate, according to City College’s project management consultants. 


“We’re trying to have a synchronicity between when SFMOMA is contractually done with [the mural], and when we have a place to move it in so [it] doesn’t have to go to storage again,” Maynez said.  


The district established a construction budget with a cap of $81 million, and even with 

the industry standard of $1,400 per square foot, the board’s requirement of a 70,000-square-foot building puts the project over budget, according to Music Department Chair Madeline Mueller. 


According to Zepeda, the college has to follow the Multi-Year Budget and Enrollment Plan. City College is currently looking for another DBE, and even though they can’t pay market rate, Zepeda is confident the college will find one because construction companies have lost contracts during the pandemic. 


When asked what happens if the new theater isn’t finished in time, Zepeda said, “I don’t 

deal with what ifs.” She said the mural is a “huge responsibility, and we want it to be here for another 100 years.” 


The images of the mural will be free to view, but not downloadable due to copyright and 

licensing restrictions, Schroer said. CHI has to have the images ready by the end of January, and Schroer is hoping they’ll be available to the public shortly thereafter. 


The Guardsman