Mission Bay Developers Take on Quake Challenges

Buildings, Parks Need Expensive Extra Work

Steve Ginsberg

The build-out of Mission Bay posed the question: What type of construction will hold up there should a magnitude 7.0 quake hit the region? Mission Bay, which was once actually a bay, contains some of the least stable soil in San Francisco.

“The biggest problem at Mission Bay is that the ground is bay mud. It’s like building on a bed of Jell-O. You need to drive pre-cast piles,” said engineer Kurt Lindorfer, a principal at Paradigm Structural Engineers who has worked in Mission Bay on Alexandria’s biotech buildings. “From a proximity stand point, Mission Bay is a lot farther from a fault line than many other places. It’s farther from the San Andreas and Hayward fault lines, seismically speaking, but because of its soil, it presents a series of problems.”

When landfill settles, there are often myriad maintenance issues a landlord must face in an earthquake’s aftermath. Much of Loma Prieta’s damage was caused by the settling and liquefaction of sand, engineers and seismologists acknowledge. But Loma Prieta’s lessons were not the most valuable, according to Lindorfer.

“The lessons we learned from the (1994) Northridge earthquake were really more important than the lessons we learned from Loma Prieta, as it pertains to Mission Bay. Before Northridge, we thought we were in good shape with the kinds of buildings we had. Since then, construction techniques have become more stringent.”