Loma Prieta Case Study

17th October 1989

The earthhquake measured 6.9 on the Richter Scale

The epicentre was 10 milles from Santa Cruz in northern California

Occurred on the San Andreas Fault

Tremors lasted for 15 seconds

Bay Bridge and the Nimitz Freeway both partially collapsed - Bay Bridge was rebuilt within a month but the Nimitz Freeway had to be demolished and was not rebuilt until 1997

Traffic was brought to a standstill

Homes were left without power (an estimated 1.4 million people were affected)

Fans ran on to the Candlestick baseball stadium as the whole stadium swayed

63 people were killed (it was initially reported as 300 but the figure was lower than expected because many people had left work early to watch the World Series Baseball on TV so there was less traffic on the roads)

3,500 were injured

100,000 buildings were damaged

12,000 people were made homeless

242 buildings were damaged at Stanford University

San Francisco suffered 22 structural fires

The War Memorial Opera House in San Francisco was damaged

Buildings in downtown Santa Cruz were destroyed - they consisted of unreinforced masonary and were at least 50 - 100 years old so weren't built to survive

Soil liquifaction in San Francsico's Marina District, where houses had been built on water-saturated unconsolidated mud, sand and rubble

The earthquake cost $4.4 billion

House prices in the area fell by 2%

1/4 of all businesses in Santa Cruz suffered damage, which affected their ability to trade

Good media coverage of the event

Underground transport was shut down

Traffic was stopped from going on the damaged bridges

There was not enough emergency communication to manage all information and resources effectively

On 26th October, President George H. W. Bush signed a $1.1 billion earthquake relief package for California and private donations also contributed to the aid given

The Governor of California, George Deukmajian, declared there would be an enquiry to discover why the highways hadn't survived despite being constructed to survive larger earthquakes than this one

The War Memorial Opera House shut for 18 months and had  a $49.5 million seismic retrofit

Damaged bridges and buildings were rebuilt and improvements were made to avoid a reoccurance of the event

Better education, with an increase in drills and more practices so people would know what to do

The Seismic Hazards Mapping Act was passed in 1990, requiring land developpers to address earthquake hazards in high-risk areas (i.e. deemed likely to suffer from ground tremors, soil liquefaction etc.)