Is San Francisco really sinking? | KALW

Is San Francisco really sinking?

Feb 21, 2019


Listener Alexjandra Rodriguez asked us, “Does San Francisco sink, or is it the whole Bay Area?”

Spinnaker Way at Caesar Chavez Park in Berkeley is a bumpy and undulating road because it’s sinking. Roland Burgmann, a professor in the Earth and Planetary Sciences department at University of California, Berkeley, says before it started sinking, the road was built “straight and flat.”

Burgmann and I are standing on top of sinking land and we can also see more sinking land across the bay. Specifically, we can see Treasure Island, where Burgmann says the northwest corner “is going down especially fast.”

Additionally, parts of South San Francisco, Alameda, and Foster City are also sinking. Places built on top of landfill or mud (like Treasure Island or Caesar Chavez Park) are sinking. Burgmann says Caesar Chavez Park used to be a real landfill, so "there’s a lot of trash.”

And as the land sinks, in some places as much as half an inch per year, the sea level around the bay is also rising at about one-tenths of an inch per year. In these areas where the water is rising and the land is sinking, Burgmann says it’s possible that one day, “they will no longer be places you can walk on.”

One thing people can do is reduce the amount of water they pump from the ground, for things like drinking water, because pumping out the groundwater only makes the land sink faster. If people don’t take any action, Burgmann says many places in the Bay Area are going to be underwater in 50 years.