The Bay’s colorful salt ponds are fading, and that’s a good thing
By Angela Johnson
10 May 2017
Photo courtesy Charles Benton
Almost everyone who flies into San Francisco or San Jose airport has seen it -- a vibrant patchwork quilt of colorful water. There, on the southern edge of the San Francisco Bay, you can see bright pinks, pumpkin oranges, neon greens and deep magentas, contrasted against the dark blues of the natural bay water.
To get the best view, it helps to have a kite. Just ask College of Environmental Design Professor Emeritus of Architecture and kite aerial photographer Charles Benton. You can find him on the South Bay shoreline most weekends, talking to his kite like a pet as he slowly coaxes it up into the air.
“It’s just absolutely wonderful holding this line and being connected to this big invisible mass of air that’s floating past us...very satisfying,” he says as he unravels the kite line through a worn leather glove on his right hand.
Benton’s kite is red, blue and white, with a long tail that looks like a red feather boa. But the really cool thing about it is how he can fasten a digital camera to the line and send it up hundreds of feet in the air to snap pictures below.
“When I first started photographing down here, it was largely an intoxication with the sort of color and texture of the place,” Benton says.
That was over a decade ago when Benton took a sabbatical from his job as an architecture professor at CED to work with a microbiologist. The biologist photographed the Bay Area landscape from his microscope, and Benton captured the same area from above. One day, they came here, to the water’s edge of the South Bay. “I was immediately taken with the visually exuberant landscape, and now this is 10 years later, and I’m still photographing.”
This visually exuberant landscape -- the reds and the corals and deep oranges outlined with bright white borders -- looks like it could be natural, but the colorful squares are man-made salt ponds engineered to extract and harvest salt from the salinity of the bay water. All 8,000 acres of ponds are now managed by a company named Cargill.
“Cargill is harvesting about 600 tons of salt here in the South Bay. You can see the big stack of salt down in Newark. It’s the one remaining salt plant,” Benton says.
The mud and the Mediterranean climate make it a great place to harvest salt from the water. A handful of family-owned businesses kickstarted the industry over a century ago, before they were all bought up by Cargill.
“These are the remnants of really what is still an active enterprise, the evaporation of bay water to produce salt for industrial use and sometimes for the culinary use,” Benton says.
Salt making is a pretty simple process. Slightly salty bay water flows into one pond and then gravity does its magic. The salt water works its way from pond to pond to pond. As it does, it gets saltier and saltier through evaporation. “Those are colors related to the salinity of the salt ponds, and they are produced by microorganisms,” says Benton.
As the water gets saltier, fewer things can survive in it, and that’s why we get those magenta and bright pink colors: only a few types of algae and bacteria can bear the saltiest of ponds. They’re called halophiles -- salt lovers -- and they tend to be pretty colorful.
“So each band of salinity will host one or two types of halophiles, they go through a whole range of greens, reds, oranges and yellows,” Benton says.
Benton moves his camera with a radio airplane controller. He walks around for hours, adjusting the camera and taking photos every other second, sometimes running back and forth to make sure the camera doesn’t fall into the water. He likes to use a kite is because it can go high enough in the air to give perspective, but low enough to notice the changes in the landscape, and changes away from commercial salt.
“I am trying to capture the transition we are experiencing today, which is as rapid and dramatic as anything that has happened before, and it's going in a happy direction, too,” he says.
As part of a huge effort called the South Bay Salt Pond Restoration Project, the Cargill salt company has freed almost 16,000 acres of their salt ponds, managing them for wildlife instead and slowly transforming them back into their natural state: marshlands.
So far, the project has restored about half a dozen salt ponds in the South Bay, with three more coming in the next five years. In response, Bay Area specific species like the salt marsh harvest mouse and a bird called the Ridgeway’s Rail have bounced back.
Benton witnesses this shift from the camera on his kite: “I won’t say to my dismay as a photographer, but to my slight regret as a photographer, it's a landscape that’s changing from the very exuberant colors of salt making, the bright greens and fuchsias and oranges and reds to a more natural tones as salt making goes its way to restored marsh.”
View more of Professor Emeritus Benton's work here.