The
Northridge earthquake occurred on January 17 1994 at 4:31 AM
Pacific Standard TimeThe Pacific Time Zone observes standard time by subtracting eight hours from Coordinated Universal Time . The clock time in this zone is based on the mean solar time of the 120th meridian west of the Greenwich Observatory. During daylight saving time, its time offset is UTC-7.In the United States...
in
ResedaReseda is a San Fernando Valley district in the city of Los Angeles, California.- History :The area now known as Reseda was originally inhabited by Native Americans of the Tongva tribe that lived close to the Los Angeles River...
, a neighborhood in the city of
Los Angeles, CaliforniaLos Angeles is the largest city in the state of California and the second largest in the United States. Often abbreviated as L.A. and nicknamed The City of Angels, Los Angeles has an estimated population of 3.8 million and spans over in Southern California...
, lasting for about 20 seconds. The
earthquakeAn earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are recorded with a seismometer, also known as a seismograph...
had a "strong"
moment magnitudeThe moment magnitude scale is used by seismologists to measure the size of earthquakes in terms of the energy released...
of 6.7, but the
ground accelerationPeak ground acceleration is a measure of earthquake acceleration on the ground and an important input parameter for earthquake engineering....
was one of the highest ever instrumentally recorded in an urban area in North America. Seventy-two deaths were attributed to the earthquake, with over 9,000 injured. In addition, the earthquake caused an estimated $20 billion in damage, making it one of the costliest natural disasters in U.S. history.
Epicenter
The earthquake struck in the
San Fernando ValleyThe San Fernando Valley is an urbanized valley located in Southern California, United States. More than half of the city of Los Angeles' land area lies within the San Fernando Valley...
about 20 miles (31 km) northwest of downtown Los Angeles near the community of
NorthridgeNorthridge is a community in the San Fernando Valley region of the City of Los Angeles, California, United States.The 1994 Northridge Earthquake is named for the community based on early estimates of the location of the quake's epicenter; however further refinements showed it to be technically in...
. The actual epicenter of the quake was in Reseda, near the intersection of Reseda Blvd. and Saticoy St. However, it took several days to pinpoint the epicenter with accuracy, and in the meantime the media had already dubbed it "The Northridge Earthquake." The name stuck, in part due to the extensive damage and loss of life in Northridge. The
National Geophysical Data CenterThe National Geophysical Data Center provides scientific stewardship, products and services for geophysical data describing the solid earth, marine, and solar-terrestrial environment, as well as earth observations from space....
places the hypocenter's geographical coordinates at and a depth of 17 km (10.56mi). Despite the area's proximity to the
San Andreas FaultThe San Andreas Fault is a continental transform fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip...
, the Northridge quake did not occur along this fault, but rather on a previously-undiscovered
blind thrust faultA thrust fault is a type of fault, or break in the Earth's crust across which there has been relative movement, in which rocks of lower stratigraphic position are pushed up and over higher strata. They are often recognized because they place older rocks above younger. Thrust faults are the result...
.
Damage and fatalities
Damage occurred up to 85 miles (125 km) away, with the most damage in the west San Fernando Valley, and the cities of
Santa MonicaSanta Monica is a city in western Los Angeles County, California, USA. Situated on Santa Monica Bay, it is surrounded on three sides by the city of Los Angeles — Pacific Palisades on the northwest, Brentwood on the north, West Los Angeles on the northeast, Mar Vista on the east, and Venice on the...
,
Simi ValleySimi Valley is an incorporated city located in a valley of the same name in the southeast corner of Ventura County, California, bordering the San Fernando Valley of Los Angeles in the Greater Los Angeles Area...
and
Santa ClaritaSanta Clarita is the fourth largest city in Los Angeles County, California, United States and the twenty-sixth largest city in the State of California. The California Department of Finance estimated the city population as of January 1, 2009 at 177,150. Including unincorporated areas of the Santa...
. It is estimated that at least 57 people died as a result of the earthquake and as many as 72 deaths were attributed to the quake. More than 8,700 were injured including 1,600 that required hospitalization. The Northridge Meadows apartment complex was one of the well-known affected areas in which sixteen people were killed as a result of the building's collapse. The
Northridge Fashion CenterNorthridge Fashion Center is a large shopping mall located in Northridge, California. It opened in 1971. It was severely damaged during the Northridge Earthquake in 1994, but renovated extensively in 1995 and 1998.-Anchors & Majors:*Borders Books & Music...
also sustained very heavy damage—most notably, the collapse of parking structures. The earthquake also gained worldwide attention because of damage to the vast freeway network, which serve millions of commuters everyday. The most notable of this damage was to the Santa Monica Freeway, Interstate 10, known as the busiest freeway in the United States, congesting nearby surface roads for three months while the freeway was repaired. Further north, Interstate 5 (the Golden State Freeway) and
State Route 14State Route 14 is a north-south state highway in the U.S. state of California, largely in the Mojave Desert. The southern portion of highway is signed as the Antelope Valley Freeway. The route connects Interstate 5, or Golden State Freeway, near Santa Clarita, with U.S. Route 395, near Inyokern...
(the Antelope Valley Freeway) collapsed and had to be rebuilt. The
Newhall Pass interchangeThe Newhall Pass Interchange is a highway interchange at Newhall Pass, north of San Fernando in Southern California, United States. It connects Interstate 5 with State Route 14 , and includes truck bypass roadways...
of Interstate 5 and
State Route 14State Route 14 is a north-south state highway in the U.S. state of California, largely in the Mojave Desert. The southern portion of highway is signed as the Antelope Valley Freeway. The route connects Interstate 5, or Golden State Freeway, near Santa Clarita, with U.S. Route 395, near Inyokern...
collapsed as it had 23 years earlier during the 1971
Sylmar earthquakeThe 1971 San Fernando earthquake struck the San Fernando Valley near Sylmar at 6:00:55 a.m. PST on February 9 1971, with a magnitude of 6.6....
even though it had been rebuilt with improved structural components. One life was lost in the Newhall Pass interchange collapse:
LAPDThe Los Angeles Police Department is the police department of the city of Los Angeles, California. With nearly 9,900 officers and more than 3,000 civilian staff, covering an area of with a population of more than 3.8 million people, it is one of the largest law enforcement agencies in the United...
motorcycle officer Clarence W. Dean fell 40 feet from the damaged connector from southbound 14 to southbound I-5 along with his motorcycle. Because of the early morning darkness, he was unaware that the elevated roadway beneath him had dropped, and was unable to stop in time to avoid the fall and died instantly. When the interchange was rebuilt again one year later, it was renamed the Clarence Wayne Dean Memorial Interchange in his honor.
Additional damage occurred about 50 miles south in
AnaheimAnaheim is a city in Orange County, California. As of January 1, 2009, the city population was about 348,467, making it the 10th most-populated city in California and ranked 54th in the United States. The city anticipates that the population will surpass 400,000 by 2014 due to rapid development...
as the scoreboard at
Anaheim StadiumAngel Stadium of Anaheim is a modern-style ballpark located in Anaheim, California. It is the home ballpark to Major League Baseball's Los Angeles Angels of Anaheim of the American League, and was previously home to the NFL's Los Angeles Rams...
collapsed onto several hundred seats. The stadium was empty at the time. Although several commercial buildings also collapsed, loss of life was minimized because of the early morning hour of the quake, and because it occurred on a Federal holiday (Martin Luther King, Jr. Day). Also, because of known seismic activity in California, area
building codeA building code, or building control, is a set of rules that specify the minimum acceptable level of safety for constructed objects such as buildings and nonbuilding structures. The main purpose of the building codes is to protect public health, safety and general welfare as they relate to the...
s dictate that buildings incorporate structural design intended to withstand earthquakes. However, the damage caused by the earthquake revealed that some structural specifications did not perform as well as expected. Because of this building codes were revised. Some structures were not
red-taggedA red-tag is applied to a structure in the United States if it has been severely damaged to the degree that the structure is too dangerous to inhabit. Similarly, a structure is yellow-tagged if it has been moderately damaged to the degree that its habitability is limited...
until months after the earthquake because damage was not immediately apparent.
The quake produced unusually strong ground accelerations in the range of 1.0
gThe g-force experienced by an object is its acceleration relative to free-fall. The term g-force is considered a misnomer, as g-force is not a force but an acceleration....
. Damage was also caused by fire and landslides. The Northridge earthquake was notable for striking almost the same area as the M
W 6.6 San Fernando (Sylmar) Earthquake. Some estimates of total damage range as high as $25 billion.
Most casualties and damage occurred in multi-story wood frame buildings (e.g. the three-story Northridge Meadows apartment building). In particular, buildings with an unsteady first floor (such as those with parking areas on the bottom) performed poorly. Numerous fires were also caused by broken gas pipes due to houses shifting off foundations or unsecured water heaters falling over. In the San Fernando Valley, several underground gas and water mains were severed, and there were some streets where there were fires burning through floods. As is common in earthquakes,
unreinforced masonry buildingAn Unreinforced masonry building is a type of building where load bearing walls, non-load bearing walls or other structures, such as chimneys are made of brick, cinderblock, tiles, adobe or other masonry material, that is not braced by reinforcing beams...
s and houses on steep slopes suffered damage. However, school buildings (K-12), which are required to be reinforced against earthquakes, in general survived fairly well.
Base isolation
Before the Northridge earthquake occurrence, a heavy
dampingIn physics, damping is any effect that tends to reduce the amplitude of oscillations in an oscillatory system, particularly the harmonic oscillator.In mechanics, friction is one such damping effect...
mechanism sometimes incorporated in
vibration controlIn earthquake engineering, vibration control is a set of technical means aimed to mitigate seismic impacts in building and non-building structures.All seismic vibration control devices may be classified as passive, active or hybrid where:...
technologies and, particularly, in
base isolation devices was considered a valuable source of suppressing vibrations thus enhancing a building's seismic performance. However, for the very pliant systems such as
base isolated structureStructure is a fundamental and sometimes intangible notion covering the recognition, observation, nature, and stability of patterns and relationships of entities...
s, with a relatively low bearing
stiffnessStiffness is the resistance of an elastic body to deformation by an applied force. It is an extensive material property.-Definition:The stiffness, k, of a body is a measure of the resistance offered by an elastic body to deformation .whereIn the International System of Units, stiffness is typically...
but with a high damping, the so-called "damping force" turned out to be the main pushing force at this strong earthquake. This resulted in the "base isolation" buildings performing far worse than promised, and much worse than average buildings.
Valley Fever outbreak
An unusual effect of the Northridge earthquake was an outbreak of
coccidioidomycosisCoccidioidomycosis is a fungal disease caused by Coccidioides immitis or C. posadasii. It is endemic in certain parts of Arizona, California, Nevada, New Mexico, Texas, Utah and northwestern Mexico.C...
(Valley Fever), a respiratory disease caused by inhaling airborne spores. The number of cases (203) in
Ventura CountyVentura County is a county in the southern part of the U.S. state of California . It is located on California's Pacific coast. It is often referred to as the Gold Coast, and has a reputation of being one of the safest populated places and one of the most affluent places in the country...
was roughly 10 times the normal rate in the eight weeks following the earthquake and three people died. It is thought that the spores were carried in large clouds of dust created by seismically triggered landslides. Most of the cases occurred immediately downwind of the landslides.
Hospitals affected
Eleven hospitals suffered structural damage and were damaged or unusable after the earthquake. Not only were they unable to serve their local neighborhoods, they had to transfer out their inpatient populations, which further increased the burden on nearby hospitals that were still operational. As a result, the state legislature passed a law requiring all California hospitals to ensure that their acute care units and emergency rooms would be in earthquake-proof structures by January 1 2005.
Television, Movie & Music productions affected
The quake stopped production of movies and TV shows filming in the area at the time, most notably
The SimpsonsThe Simpsons is an American animated television sitcom created by Matt Groening for the Fox Broadcasting Company. The series is a satirical parody of a middle class American lifestyle epitomized by its eponymous family, which consists of Homer, Marge, Bart, Lisa, and Maggie...
season 6's first two episodes "
Bart of Darkness"Bart of Darkness" is the first episode of The Simpsons
' sixth season, which originally aired September 4, 1994. It was written by Dan McGrath, and directed by Jim Reardon. In the episode, Bart breaks his leg; his resultant isolation causes him to believe that Ned Flanders has...
" and "
Lisa's Rival"Lisa's Rival" is the second episode of The Simpsons
' sixth season, and originally aired September 11, 1994. It was the first episode to be written by Mike Scully, and was directed by Mark Kirkland. Winona Ryder guest stars as Allison Taylor, a new student at Springfield Elementary...
". ABC's
General HospitalGeneral Hospital is an American daytime television drama and is currently credited by the Guiness Book of World Records as being the second longest-running soap opera in production and the second longest running drama in television in production. It premiered on the ABC television network on April...
, which tapes in Los Angeles, was also heavily affected by the Northridge earthquake. The set, which is at ABC Television Center, suffered major damage via partial collapse and water damage.
All of the earthquake sequences in the
Wes CravenWesley Earl "Wes" Craven is an American film director and writer, perhaps best known as the creator of many horror films, including the famed A Nightmare on Elm Street series featuring the iconic Freddy Krueger character and the Scream films.-Early life:Craven was born in Cleveland, Ohio, the son...
movie
New Nightmare were actually filmed a month prior to the Northridge quake. The real quake struck only weeks before film was completed. Subsequently, a team was sent out to film footage of the actual quake damaged areas of the city. The cast and crew thought that the scenes that were filmed before the real quake struck were a bit overdone, but when viewed after the real quake hit, they were horrified by the realism of it.
Michael JacksonMichael Joseph Jackson , known as the "King of Pop", was an American musician and one of the most commercially successful and influential entertainers of all time...
had been due to begin recording of his new album
HIStoryHIStory: Past, Present and Future, Book I is a double album by Michael Jackson, released on June 16, 1995. The first disc is his first hits collection, whereas the second is his studio album. HIStory is the best-selling multiple disc album ever, with worldwide sales of over 20 million copies...
on the day of the earthquake. A recording studio had just been refurbished at a cost of "several" million US dollars, but Jackson's entourage moved recording to
New York CityNew York is the most populous city in the United States, and the center of the New York metropolitan area, which is among the most populous urban areas in the world. A leading global city, New York exerts a powerful influence over worldwide commerce, finance, culture, fashion and entertainment...
. They returned to the new studio in
Los AngelesLos Ángeles is the capital of the province of Biobío, in the municipality of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123.445 inhabitants...
some six months later.
Transportation affected
Freeways, including the interchange of the
Interstate 5Interstate 5 is the main Interstate Highway on the West Coast of the United States, paralleling the Pacific Ocean from Canada to Mexico and serving some of the largest cities of that part of the U.S., including Seattle, Tacoma, Portland, Sacramento, San Francisco/Oakland, Los Angeles, and San Diego...
with the
California State Route 14State Route 14 is a north-south state highway in the U.S. state of California, largely in the Mojave Desert. The southern portion of highway is signed as the Antelope Valley Freeway. The route connects Interstate 5, or Golden State Freeway, near Santa Clarita, with U.S. Route 395, near Inyokern...
,
Interstate 10Interstate 10 is the southernmost east-west, coast-to-coast Interstate Highway in the United States. It stretches from the Pacific Ocean at State Route 1 in Santa Monica, California to Interstate 95 in Jacksonville, Florida...
,
California State Route 118State Route 118 is a state highway in the United States state of California that begins running west to east through Ventura and Los Angeles counties in southern California. It travels from Saticoy in Ventura County east to Lake View Terrace in Los Angeles...
were closed because of the collapse. The Metro Bus & Metrolink suspended all services until the next day. Many flights into and out of
Los Angeles International AirportLos Angeles International Airport is the primary airport serving Los Angeles, California, the second-most populated metropolitan area of the United States. It is often referred to by its airport code LAX, with the letters usually pronounced individually...
(LAX), on the day of the earthquake, were delayed or cancelled. Other airports in the Los Angeles Area were also closed including Burbank Glendale Pasedena Airport (Now
Bob Hope AirportBob Hope Airport is a public airport located three miles northwest of the central business district of Burbank, a city in Los Angeles County, California, United States...
).
Universities, Colleges, Schools affected
California State University Northridge was the only major university near the epicenter. Many campus buildings were heavily damaged and a parking structure collapsed; as a result, many classes were moved to temporary structures. Los Angeles Unified School District closed local schools throughout the area, classes were rescheduled for couple of days. UCLA & other universities were also shut down.
Other Buildings affected
The United States Postal Service suspended all mail service throughout the Los Angeles area for few days,
Los Angeles Public LibraryThe Los Angeles Public Library system serves the residents of Los Angeles, California, United States. With over 6 million volumes, LAPL is one of the largest publicly funded library systems in the world. The system is overseen by a Board of Library Commissioners with five members appointed by the...
shut down most of its branches, books were knocked down after the quake. Many Shopping Malls including the
Sherman Oaks GalleriaSherman Oaks Galleria is a shopping mall and business center located in the Sherman Oaks neighborhood of Los Angeles, California, United States, at the corner of Ventura and Sepulveda Boulevards in the San Fernando Valley....
& Other Shopping malls were also shut down.
Legislative changes
The Northridge earthquake led to a number of legislative changes. Due to the large amount lost by insurance companies because of the earthquake, most insurance companies either stopped offering or severely restricted earthquake insurance in California (and elsewhere). In response, the California Legislature created the
California Earthquake AuthorityEstablished in September 1996 by the California Legislature, theCalifornia Earthquake Authority is a privately funded, publiclymanaged organization that sells California earthquake insurance policiesthrough participating insurance companies....
(CEA), which is a publicly managed but privately funded organization that offers minimal coverage. A substantial effort was also made to reinforce freeway bridges against seismic shaking, and a law requiring water heaters to be properly strapped was passed in 1995.
Closures
- Interstate 10
Interstate 10 is the southernmost east-west, coast-to-coast Interstate Highway in the United States. It stretches from the Pacific Ocean at State Route 1 in Santa Monica, California to Interstate 95 in Jacksonville, Florida...
Santa Monica Freeway
- Los Angeles International Airport
Los Angeles International Airport is the primary airport serving Los Angeles, California, the second-most populated metropolitan area of the United States. It is often referred to by its airport code LAX, with the letters usually pronounced individually...
(Closed for Inspection)
- Universal Studios Hollywood
Universal Studios Hollywood is a movie studio in the Universal City community of unincorporated Los Angeles County, California, United States, and is the original Universal Studios theme park. Woody Woodpecker is the mascot for Universal Studios Hollywood and the rest of the Universal Studios Theme...
(Including the Earthquake Ride)
- Disneyland
Disneyland is an American theme park in Anaheim, California, owned and operated by the Walt Disney Parks and Resorts division of The Walt Disney Company. It was dedicated with a press preview on July 17, 1955, and opened to the general public July 18, 1955...
(Closed for Inspection, Except for the construction of the Indiana Jones AdventureIndiana Jones Adventure: Temple of the Forbidden Eye is a dark ride attraction within Adventureland at Disneyland. It opened on March 3, 1995. Based on the Indiana Jones films, guests accompany intrepid archeologist Dr. Indiana Jones on a turbulent high speed adventure through a dangerous lost...
)
- Capitol Records
Capitol Records is a major United States-based record label owned by EMI and located in Los Angeles and New York City as part of Capitol Music Group...
(Some Damages, also a stoppage of recording of musicMusic is an art form whose medium is sound. Common elements of music are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
.)
- Six Flags Magic Mountain
Six Flags Magic Mountain is an amusement park located in Valencia, California north of Los Angeles. It opened on Memorial Day weekend on May 29, 1971 as Magic Mountain, by the Newhall Land and Farming Company...
(Psyclone, suffered some damage), was a contributing factor to the demise of Psyclone in 2007
- Hollywood Bowl
The Hollywood Bowl is a famous modern amphitheatre in the Hollywood area of Los Angeles, California, USA, that is used primarily for music performances...
- Anaheim Stadium
- Crystal Cathedral
The Crystal Cathedral is a Protestant Christian megachurch in the city of Garden Grove, in Orange County, California, United States. The prominent architect Philip Johnson designed the main sanctuary building, which was constructed using over 10,000 rectangular panes of glass and can hold...
- Interstate 5
Interstate 5 is the main Interstate Highway on the West Coast of the United States, paralleling the Pacific Ocean from Canada to Mexico and serving some of the largest cities of that part of the U.S., including Seattle, Tacoma, Portland, Sacramento, San Francisco/Oakland, Los Angeles, and San Diego...
and California State Route 14State Route 14 is a north-south state highway in the U.S. state of California, largely in the Mojave Desert. The southern portion of highway is signed as the Antelope Valley Freeway. The route connects Interstate 5, or Golden State Freeway, near Santa Clarita, with U.S. Route 395, near Inyokern...
in Santa ClaritaSanta Clarita can refer to:* Santa Clarita, California* Santa Clarita Valley...
External links