HAZARDS AND THREATS
The greatest Southern California earthquake in modern history was the Fort Tejon Earthquake on January 9, 1857 that measured 8.0 on the Richter Scale. Damage was not nearly as serious as it would be today, mostly because Southern California was sparsely populated. The effects of the quake were quite dramatic, even frightening. Were the Fort Tejon shock to happen today, the damage would easily run into billions of dollars, and the loss of life would be substantial. The present-day communities of Wrightwood and Palmdale lie upon or near the 1857 rupture area. The greatest Southern California earthquake in modern history was the Fort Tejon Earthquake on January 9, 1857 that measured 8.0 on the Richter Scale. Damage was not nearly as serious as it would be today, mostly because Southern California was sparsely populated. The effects of the quake were quite dramatic, even frightening. Were the Fort Tejon shock to happen today, the damage would easily run into billions of dollars, and the loss of life would be substantial. The present-day communities of Wrightwood and Palmdale lie upon or near the 1857 rupture area. On March 10, 1933 at 5:54 p.m., a magnitude 6.4 earthquake hit the Newport-Inglewood Fault, causing serious damage in Long Beach and other communities. The earthquake resulted in 120 deaths and more than $50 million in property damage. Most of the damaged buildings were of unreinforced masonry.
More recent earthquakes have caused severe damage, but none would be classified as a “major” temblor.
The San Fernando Earthquake hit at 6:01 a.m. on February 9, 1971. It caused more than $500 million in damage and 65 deaths.
The Whittier Narrows Earthquake struck on October 1, 1987 at 7:42 a.m. and registered magnitude 5.9. It caused eight deaths and $358 million in property damage.
The Sierra Madre Earthquake was magnitude 5.8 and occurred on June 28, 1991 at 7:43 a.m. Because of its depth and moderate size, it caused no surface rupture, though it triggered rockslides that blocked some mountain roads. It caused about $40 million in property damage and two deaths, mostly in the San Gabriel Valley.
The magnitude 6.7 Northridge Earthquake struck at 4: 31 a.m. on January 17, 1994. This earthquake caused 57 deaths and a FEMA-estimated $40 billion in property damage. An estimated 12,000 people were injured, and 100,000 structures were damaged. More than 600,000 individuals applied for disaster assistance.
Want more information about earthquakes? Check out our links page
Residence that was “red tagged” due to damage from the 1994 Northridge Earthquake.
Los Angeles County is well known as one of the world’s great urban centers, but the county is also home to the 650,000-acre Angeles National Forest and a large portion of the Santa Monica Mountains National Recreational Area. Thousands of homes are located in foothill communities near these great natural areas, creating unique challenges for local fire agencies.
Since 1927, a total of 24 wildland fires have caused the loss of 1,502 homes, 830 other structures, 271,047 acres and five fatalities. The most recent major wildfires erupted in Los Angeles and surrounding counties starting in the Angeles National Forest above Altadena on October 27, 1993. Fires in Altadena and Malibu caused the loss of many homes.
Floods and mudslides
Los Angeles County contains some of the steepest and most erosive mountains in the world, the San Gabriels, with elevations reaching 10,000 feet above sea level. Below steeply walled canyons lie large coastal plains with a high population density. When heavy rains come, there is a significant potential for floods and mudslides.
In 1914, when the population of the Los Angeles Basin was about 700,000, a four-day storm produced more than 19 inches of rain in the San Gabriel Mountains, resulting in floods causing $10 million in damage.
Floods in 1938 caused $70 million in damage in Southern California, and in 1969, floods caused $400 million in damage and 60 deaths.
In the 1990s, serious flooding happened in 1992, ’93, ’95, and ’98.
How can you protect yourself against floods? Consider flood insurance and home preparedness measures – for more information click here.
Significant events of civil disorder are uncommon in the Operational Area, but have occurred twice in recent history. On August 11, 1965, six days of rioting began in the Watts section of Los Angeles. In the violence, 34 people were killed and 856 injured.
On April 29, 1992, just hours after a Simi Valley jury acquitted four LAPD officers in the Rodney King trial, civil disorder erupted, resulting in 58 deaths.
Click here to see a listing of all State and federally declared disasters in Los Angeles County since 1950. Information provided the California Office of Emergency Services.
Hazards and Threats
- Maintaining an approved Operational Area Emergency Response Plan.
- Providing ongoing leadership and coordinating disaster plans and exercises with the 88 cities, 137 unincorporated communities and 288 special districts in the county.
- Assisting County departments to develop department emergency plans which address how they will perform both their non-deferrable missions and Operational Area duties during disasters.
- Assisting County departments with development of facility emergency plans for every occupied County facility.
- Supporting and advising the Board of Supervisors, Emergency Management Council and Emergency Preparedness Commission.
- Supporting and advising the Board of Supervisors in matters pertaining to their role as elected officials during emergencies and disasters.
The Los Angeles County Operational Area (LACOA) is known for its famous sunshine, beaches, mountains and deserts, but on occasions the area may experience Extreme Heat in the Antelope and Santa Clarita Valleys, San Fernando and San Gabriel Valleys, and other parts of the LACOA. During periods of Extreme Heat, there may be an increase in heat exhaustion, heat cramps and sunstroke.
Heat may worsen the affects of poor air quality in areas of heavy smog. If you plan to be outdoors, take precautions to protect yourself from the heat.
Landslides, Mud and Debris Flows
- Landslide Introduction
- What to Do Before Storms and Heavy Rainfall
- What to Do During Storms and Heavy Rainfall
- Where Do Landslides Occur
- Landslide Mitigation
- Web Resources
- Terms and Definitions
- History in Los Angeles County Operational Area
Pandemic Flu Brochures
- Pandemic Flu Brochure – Arabic
- Pandemic Flu Brochure – Armenian
- Pandemic Flu Brochure – Chinese
- Pandemic Flu Brochure – Farsi
- Pandemic Flu Brochure – Khmer
- Pandemic Flu Brochure – Korean
- Pandemic Flu Brochure – Russian
- Pandemic Flu Brochure – Spanish
- Pandemic Flu Brochure – Tagalog
- Pandemic Flu Brochure – Thai
- Pandemic Flu Brochure – Vietnamese
- Pandemic Flu Brochure – English
What Causes Power Outages?
- Excavation Digging
- High Power Demand
- Outage Information
- Preparation Checklists and Other Information
- Carbon Monoxide Information
- Using a Generator Information
- Rotating Electric Outages – Preparedness
- Web Resources
- Southern California Edison’s Electricity Safety Program Information
- Additional Information from Southern California Edison on Portable Generators
- Power Lines
- Frequently Asked Questions (provided by Southern California Edison)
- ESP Focus Sheet – Heat Wave
- SCE New Mobile Outage Reporting App
CAISO Flex Alerts
The Los Angeles County Sheriff’s Department Emergency Operations Bureau is responsible for
coordinating responses to terrorism in Los Angeles County. Please visit the Sheriff’s website for
- “Volcano” the movie filmed at the L.A. County Emergency Operations Center