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A new, revised map of San Francisco has hit the stands. Not a street map or a bus map. It's a map of the city's underground waterways, and it includes a change to what could be San Francisco's oldest urban legend. KQED's Amy Standen reports.
AMY STANDEN, BYLINE: This is a story about creek geologists - people who study underground waterways. And I don't think it's going out on a limb to say that this is the only such story you'll ever hear that begins in the basement of a porn studio.
JANET SOWERS: Water's welling up from the bottom, from underneath and there's bubbles coming up through it.
STANDEN: This is Janet Sowers.
CHRISTOPHER RICHARD: Well I can hear the bubbles coming up...
STANDEN: And that's Christopher Richard. They're in the studios of Kink.com in San Francisco. It's an online fetish pornography studio that happens to have a stream running through its basement. We're told to stay clear of the actors.
UNIDENTIFIED WOMAN: Yeah.
UNIDENTIFIED WOMAN: We're making porno over here.
STANDEN: Sowers and Richard are water detectives and map makers. They look for clues of the old creeks and marshes that once ran across the city and were long ago paved over. One of those clues is above ground, a short walk away.
So we're going to...
RICHARD: Camp and Albion. Yeah, so we got a couple more blocks to go.
STANDEN: Richard is taking me to see a bronze plaque, in the heart of the city's Mission District. It's the setting of a mystery that has nagged him for years.
RICHARD: The site of the original Mission Dolores Chapel and Dolores Lagoon. On June 29th, 1776...
STANDEN: According to the legend, Spanish settlers set up camp here on the shores of a lake called Laguna Dolores, where Ohlone Indians fished and canoed. But that, Richard says, can't be. He pulls out a topographical map, and points to the place we're standing right now. He says back in the 18th century, it overlooked a creek bed, a canyon.
RICHARD: What just really nobody can explain is how you would've had a 40-foot deep canyon here...
STANDEN: And above it, a lagoon. This is gravitationally impossible. How can you have a lagoon on a ridge above a creek?
RICHARD: It would've immediately drained away.
STANDEN: This fact ate at Richard, who is a curator at the Oakland Museum, so he started looking into it, combing through historical records. He says the story of the lagoon can be traced back to a single paragraph, written by the Spanish explorer Juan Batista de Anza in March, 1776.
UNIDENTIFIED MAN: (Reading) I found a good site for planting crops with irrigation by taking the water from an ojo de agua o fuente.
STANDEN: Christopher Richard says de Anza is actually talking about three separate bodies of water, not one. But when historians read this, they got confused. Where de Anza described a creek, they thought he was talking about a lake.
RICHARD: It's all just a big misunderstanding, but it has become legend.
STANDEN: Richard's work has ignited a controversy. One local resident, who helped get the plaque put up, said he was too angry to even be interviewed for this story. He and others spent years researching the lagoon and its history. Now someone's telling them they were wrong?
Back on Albion Street, a car pulls into a nearby driveway. Tom Schmidt, a software engineer gets out.
TOM SCHMIDT: I wish they would take it down. I don't like the sign. I'm sorry if that sounds awful.
STANDEN: He says the tour groups are noisy. They leave trash on the sidewalk. And for what?
SCHMIDT: I guess I don't understand these things. It'd be one thing if there were still historical buildings, but there's just apartment buildings here now.
STANDEN: To mapmakers Janet Sowers and Christopher Richard, that is the whole point. We can't see anymore what this city looked like 250 years ago, so you have to use your imagination.
SOWERS: Imagine it as grassland. Imagine it with cattle grazing on it. And imagine being able to look over there and see that distance without these buildings in the way.
RICHARD: Our lives are dedicated to figuring out what is from what isn't. That's what a scientist does.
STANDEN: Richard and Sowers would like to see the plaque taken down, or at least revised. They say there's nothing really wrong with a creation myth. But they'd prefer the truth.
For NPR News, I'm Amy Standen in San Francisco.
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