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Some conversions are happening at California's missions. Not religious conversions, but seismic retrofitting. Many of the missions are made of adobe and date back to the late 1700s when Spain sent missionaries to convert Native Americans. The buildings may not withstand a major earthquake. From member station KAZU, Krista Almanzan has the story of one mission's renovations.
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KRISTA ALMANZAN, BYLINE: A heavy wooden door opens into the garden courtyard of the mission in the small seaside town of Carmel. The 220-year-old basilica stands at the far end. A crooked star-shaped window above the entry is said to symbolize that only God is perfect.
TAMAR SEKAYAN: The architecture, I think, is really what brings me here.
ALMANZAN: Tamar Sekayan and her husband, Justin, made the two-hour drive south from San Francisco. Like many Californians, she learned about the missions in elementary school.
SEKAYAN: I like going to all of the missions. It's part of California history, one I grew up with, so we wanted to stop in and check it out.
ALMANZAN: These days, the sounds and sights of the construction are just as noticeable as the centuries-old architecture. The basilica is in the middle of a seismic retrofit, so workers removed the red tile roof and replaced it with scaffolding and a protective plastic.
VIC GRABRIAN: They're going to try to put them back in the same way they were before because you'll notice if you look at this roof there's different patterns of how they've faded and everything.
ALMANZAN: That's Vic Grabrian. He's a parishioner at the Carmel Mission, member of the choir and president of the Carmel Mission Foundation. That means he's in charge of raising the money needed to restore the place.
GRABRIAN: We have to be so careful to preserve everything. When we finish the $5 million seismic retrofit, you won't be able to tell that we did a thing.
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ALMANZAN: The project involves drilling more than 300 vertical and horizontal holes into the 5-foot thick walls of the basilica and inserting steel rods. David Wessel is with the Architectural Resources Group, a historical consultant on the project.
DAVID WESSEL: They go all the way down into the foundation and in a sense kind of tie those walls together so that if there's movement the building will resist that and stay intact.
ALMANZAN: Wessel says in restoration, they have to pay close attention to the materials used, so the mission doesn't lose its character and patina of age. For example, when they start work on the dome that sits atop the basilica...
WESSEL: What that entails is the types of mortars that we've selected for repairing the cracks and the voids that have developed over time, and we're actually also developing a lime wash that will go over the top of the dome so that that will protect it from the rain and the moisture and filtration.
ALMANZAN: The last restoration on the Carmel Mission ended 60 years ago. All of California's 21 missions have undergone some work, but like Carmel, most need further repairs. Dr. Knox Mellon is the executive director of the California Missions Foundation. He says part of the challenge is location - all are near the coast and earthquake fault lines.
DR. KNOX MELLON: In retrospect, they couldn't have picked a worse place - the founders - to found the missions than the path they did in some ways.
ALMANZAN: The foundation is working to assess the condition of each mission and how much repairs will cost. At the Carmel Mission, the seismic retrofit is just the beginning of a $20 million restoration of the whole mission complex. For NPR News, I'm Krista Almanzan.