✓ Our backyard: Field Trip & The Hayward Fault

the last major earthquake on the Hayward Fault

1868 with magnitude of 6.8-7

frequency of major earthquakes on the HF

150 years between earthquakes

Consequences that could result from a potential major earthquake

• Fatalities and injuries: estimated 800 deaths (+ hundreds more from fire) and 18K injuries

• Displacement: approximately 411K displaced by damage and utility outages

• Cost: total losses estimated at $110 billion

• Water service restoration in highly affected areas take 6 weeks to 6 months

natural hazards associated with a potential earthquake

ground shaking, fault offset, liquefaction, land slides, aftershocks

Haywired Scenario: what, who, and why?

• What: A realistic M7.0 earthquake scenario on the Hayward Fault created to model cascading impacts (aftershocks, fires, infrastructure + digital outages).

• Who: Developed by the USGS with the HayWired Coalition (50+ agencies: ABAG, Bay Area cities, PG&E, BART, water districts, universities).

• Why: To guide preparedness and risk-reduction by showing what a plausible major Hayward Fault quake would look like—helping policymakers and residents strengthen resilience before the inevitable event.

Where does the fault roughly run on campus?

eastern part of campus, along the base of the Berkeley Hills, passing directly beneath the California Memorial Stadium.

different buildings retrofitted with respect to earthquake safety

• Barrows Hall received "bookends"—additional jacketing of reinforced concrete added to the ends of the building.

• The Residence Halls (like Unit 1) received exterior steel concentrically braced frames (x-braces) to prevent structural swaying and collapse.

• Latimer and Hildebrand Halls (Chemistry buildings) received external concrete exoskeletons and internal unbonded braces, respectively, to resist shear forces.

How does fault interact with the stadium

• The fault passes directly beneath the field, subjecting the structure to persistent tectonic stress and creep damage.

• The fault creep split the exterior wall in Section KK, where a gap of up to 50 centimeters (nearly 20 inches) developed over decades and is still visible today.

How much motion occurs on the Hayward Fault per year?

long-term slip rate: 10 mm/yr

creep rate: 4 mm/yr
about 6 mm/yr of strain is accumulating on locked segments of the fault

How did Founder’s rock get to its current position?

hypothesis - the right-lateral strike-slip movement of the Hayward Fault carried the rock to its current position on campus, transporting it over 10 miles from the Leona Quarry in Oakland