San Francisco salt ponds: photos show their dramatic transformation
Barbara Boissant's photographs have been compared to the works of American artist Mark Rothko for their blocks of deep reds, oranges, pinks, and greens. But these hues are not mixed on a palette, they are unfiltered images of the salt ponds of San Francisco Bay.
The images, taken over a period of more than a decade, document the restoration of the area from a center of commercial salt production to its natural state of tidal marshes, mudflats, and other wetlands. The ongoing South Bay Salt Ponds Restoration Project, which began in 2003 after the land was acquired from the international food corporation Cargill, aims to restore more than 15,000 acres of salt ponds - an area roughly the size of Manhattan. This was reported by edition.cnn.com.
The rich, unnatural colors in Boissant's early photographs are the result of the water's salinity. She explains that Dunaliella salina, an algae that produces beta-carotene, a red-orange pigment, thrives in salty environments. So do pink halobacteria, as well as sea shrimp, which feed on algae and enhance the bright colors.
During the restoration, artificial dikes built to hold back water to collect salt are gradually removed, allowing the tidal systems to flow through them again.
"Those dramatic oranges, reds, purples are slowly turning to greens, dark blues, and browns," Barbara says.
Despite being less photogenic, this change is a positive sign, says Dave Helsing, executive director of the South Bay Salt Pond Restoration Project. "Our goal is to get rid of these bright colors because they are remnants of the hypersaline water left over from the days of salt mining," he adds.
In this way, it is hoped that wildlife will once again flood the area, from endangered salt marsh mice to migrating shorebirds and waterfowl, or fish such as leopard sharks and steelhead.
Barbara Boissant grew up in the area and still lives here with her two daughters. She recalls visiting the salt ponds for the first time during a third-grade science lesson. It wasn't until many years later, in 2010, when she flew over them in a helicopter, that she saw what they looked like from above.
"Visually, it was amazing," she says. And at that moment, she decided to follow the restoration of the bay over a long period of time. She started by taking to the air once a year to photograph the salt ponds. Then Covid-19 came, and unable to fly, she began experimenting with shooting from ground level and even underwater.
Today, wildlife is reclaiming space. The restored ponds and artificial nesting islands create shallow water habitat that attracts hundreds of shorebirds and ducks looking for food.
In addition to restoring wildlife, converting former salt ponds into tidal marshes will bring other benefits, such as flood protection as sea levels rise.
Another benefit is for those living in the neighborhood. The public can access the area through a network of trails and viewing platforms. If people get to know nature, they are more likely to realize its value. However, visitors should respect the wildlife and not encroach on sensitive habitats of endangered species.