How Conserving One Bit of History Revealed Another

How a 1988–2012 project conserved América Tropical and uncovered L.A.’s historic Zanja Madre

Two conservators plug holes and plaster cracks in the surface of América Tropical during the 1990 conservation of the mural

Mural: © 2022 Artists Rights Society (ARS), New York / SOMAAP, Mexico City

Photo: Nancy Kaye

By Julie Jaskol

May 11, 2022

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In 1988, Getty and the City of L.A. began the process of conserving América Tropical, a mural by Mexican artist David Alfaro Siqueiros, high on a wall overlooking historic Olvera Street.

Siqueiros had painted the piece in 1932 at the request of civic boosters, but they were shocked by his scathing depiction of American imperialism and had the scene whitewashed. For most of its existence it was invisible, but increasing interest by the Chicano mural movement and the work of Siqueiros led experts to consider whether it could be brought back to life.

Getty and the City of L.A. proposed the conservation of the mural and the construction of a protective canopy, a viewing platform on the roof of a neighboring building, and an interpretive center that would tell the artwork’s story.

Mural: © 2022 Artists Rights Society (ARS), New York / SOMAAP, Mexico City

But first their attention had to be directed downward, beneath the ground.

Constructing the canopy and platform required the support of steel columns on top of foundations dug deep into the earth, and engineers flagged the very real possibility that the Zanja Madre lay underneath the building.

The Zanja Madre, or Mother Ditch, was the canal built by L.A.’s first settlers to bring water from the L.A. River to the brand-new village that would become the city. Originally open to the air, but later encased in brick, the zanja had become covered over the years by layers of dirt and concrete as streets and structures were built over it.

“The Zanja Madre is probably the oldest piece of infrastructure in Los Angeles. Everyone agreed it was important to preserve it and keep it intact,” said Edgar Garcia, assistant general manager of El Pueblo de Los Angeles Historical Monument, which includes Olvera Street.

 Three women and two children washing clothes at the Zanja Madre (Mother Ditch). A few small buildings, visible throughout the image, appear to serve as barns

Washing Clothes at the Zanja Madre, circa 1900. Security Pacific National Bank Collection, Los Angeles Public Library

Historians knew the zanja ran underneath Olvera Street—in fact, there was a 1952 plaque and some decorative brickwork on the pavement, denoting the possible course underground. But it was difficult to tell where exactly it ran. It wasn’t unusual to hit old bricks during construction downtown. “Frequently we don’t hear about it until the zanja is already just a pile of bricks on some lot somewhere,” said Garcia.

But that’s not how Getty and the City of L.A. operate. It took years, but the mural canopy and platform were redesigned to protect the Zanja Madre and keep it in place, excavated and available for public view.

The zanja is at the heart of the founding of Los Angeles, which is the tale that El Pueblo and Olvera Street seeks to tell. It is the story of the first settlers, known as the pobladores. This group of Black, Indigenous, Spanish, and multiracial families, including 11 men, 11 women, and 22 children, had been recruited by Spain to build a town. The ditch they dug created L.A.’s first aqueduct.

Water and aqueducts are also famously at the heart of L.A.’s expansion. No history of the city is complete without mention of William Mulholland and the aqueduct that brought water from the Owens Valley and allowed L.A. to become the metropolis of today. Mulholland, the chief engineer for the L.A. Department of Water and Power (DWP), was the force behind the ambitious project. When he first started his water career in L.A., his title was deputy zanjero.

The emergence of an intact section of the Zanja Madre was the perfect opportunity to add the story of water to Olvera Street. The city and the DWP are now designing a water museum around the zanja. “We never would have fully known where it was, if not for the Siqueiros project,” said Garcia.

For conservator Leslie Rainer, who led the preservation work on América Tropical, it’s an almost magical example of stratigraphy, or the analysis of layers.

“El Pueblo has so many layers of history,” she said. “Deep down you have the Zanja Madre from the earliest days of the original pueblo. Then you have Olvera Street, which was originally a part of the town that grew around the zanja. Then you have this controversial Siqueiros mural high above it all, which emerged from its layer of whitewash. These are real physical, geographic/topographical layers, and also cultural layers. Really a timeline of various uses.”

It’s also, she points out, a cycle of rebirth. “The mural was censored and neglected, then we conserve and protect it. Now the Zanja Madre gets unearthed and reclaimed. Layer by layer,” she said.

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