Near two kilns where Mexican immigrants had fired pottery, they found figurines that had survived decades underground, including a ceramic frog, a donkey and a man riding an ox.
None of the items was considered significant enough to halt the dam expansion. But the digs had another effect, sparking interest in Prado. The resulting preservation efforts, though modest, have fulfilled Prado residents' dream of creating a vibrant historical record that will remain after they die.
Among the most ardent chroniclers of old Prado was the late Christena Fear Desborough. A descendant of one of the town's most prominent farming families, she was in her late 30s when the great flood struck.
She helped organize Prado reunions and picnics. She always asked the old-timers -- who called themselves "Rinconites" -- to bring written accounts, old photographs and other memorabilia. Onetime neighbors renewed acquaintances over sandwiches and coffee and swapped newspaper clippings and old photos.
Desborough also collected keepsakes and wrote an exhaustive and opinionated chronicle of Prado's development and destruction. In the unpublished manuscript, she took potshots at Orange County, which lobbied aggressively for the dam.
"How one county could have so much influence ... is something the average 'Rinconite' has never fully understood," wrote Desborough, who died in 1988.
Her prodding resulted in the creation of a place to display historical items, now called the Heritage Room at Corona library. A sampling of the pottery and other artifacts collected from the archeological digs is on display at the San Bernardino County Museum. The Corps of Engineers published a book on its ceramics discoveries titled "The Mexican Potters of Prado."
Randy Amelino, 50, of Corona lived a few miles from old Prado for a dozen years before learning about its history. As a member of the Toastmasters, a speech-making group that often stages historic reenactments, he portrayed Lynn Lillibridge, Neil's father, and other pioneers during a cemetery tour sponsored by the Corona Historical Preservation Society several years ago.
Later, he struck up a chance conversation with a Prado survivor at a Mexican restaurant.
"It opened my eyes," said Amelino, who owns a cleaning products company in Corona. "To have a whole place flooded out and to see that kind of destruction is something. I think it's an important part of history."
Amelino has mixed feelings about what happened. "We live in a flood zone, so we know the dam had to be there," he said. "Unfortunately, a small town had to be sacrificed for this to happen.... It's like the growth of the West. It's ever-expanding."