Jim Lienkaemper, USGS

New guide to the Hayward Fault in UC Berkeley’s backyard

Horst Rademacher invites you to lace up your walking shoes, grab a water bottle and take a leisurely tour of the most dangerous earthquake fault in the Bay Area – the one that cuts directly through the UC Berkeley campus.

His newly revised self-guided tour of the Hayward Fault takes you to Memorial Stadium, which was recently retrofitted so that it can flex with the slow creep along the fault, and the Hearst Memorial Mining Building, which floats on base isolators, with stops at the campus’s 900-foot mine shaft as well as offset curbs and streambeds at the base of the Berkeley hills. Throughout he explains the geology underlying the area, in particular Strawberry Creek Canyon, and the engineering required to build safely in a seismically active area.

The Hayward Fault slices through the Lawson adit, a mine first excavated by Berkeley mining students 100 years ago. Today, much of the mine has collapsed and is unsafe, though the seismology lab maintains an earthquake monitoring station inside. 360 image by Stephen McNally.

   

“UC Berkeley is the only major university in the world that has a dangerous earthquake fault running through its campus,” said Rademacher, a journalist, researcher in the Berkeley Seismological Laboratory and lecturer in the Department of Earth and Planetary Sciences. “While teaching my class ‘Earthquakes in Your Backyard’ and while interacting with many members of the campus community, I have noticed that most folks are not aware of this fact. I want to raise awareness of the hazard the fault poses, and want to show how much the university has done to mitigate some of the risk by spending billions of dollars on seismic retrofit and upgrades.”

Rademacher and many others in the seismology lab frequently give visitors tours of the fault, but existing guides to the nearby sites have not been comprehensive and were outdated, he said. Revising these guides became a pet project.

“It was time to put a new guide together and add a historical perspective,” he said.

Horst Rademacher uses a mirror to look down a borehole near Memorial Stadium before lowering a seismometer. Robert Sanders photo.

He suggests downloading the PDF and checking out the sites, which should take about two and a half hours and involves some hill and stair climbing. A tour can provide a good appreciation of and a healthy respect for the inevitability of seismic movement on the fault, which creeps along at a rate of a few millimeters per year and is thought to be capable of generating a magnitude 7.5 earthquake.

He notes that while engineers took great care to build the stadium to “accommodate” the fault and at the same time make it much safer, “The Hayward Fault is raising its ugly head. You can already find cracks in the ground and on stairs, you can see the movement of sections of the stadium walls. While one can retrofit and renovate a great stadium, one cannot stop the plates from drifting in their epic tectonic shift.”

2011 video about the renovation of California Memorial Stadium. (Video by Roxanne Makasdjian and Philip Ebiner)

RELATED INFORMATION

The Hearst Memorial Mining building was retrofitted with base isolators to allow the building to float during a large earthquake.