The dilemma of whether to allow new construction on active earthquake faults remains contentious. Equally pressing is the issue of the many structures already positioned over these hazardous fissures.
These concerns have emerged prominently in areas like Hollywood and other parts of Southern California, where active faults run through numerous neighborhoods.
In a notable case, the City of Los Angeles halted the construction of two skyscrapers near the Capitol Records building at Hollywood and Vine. This decision was based on concerns from the United States Geological Survey about an active fault capable of causing a magnitude 7 earthquake beneath the proposed site. Developers contested this, undertaking extensive trenching and geological studies to challenge the fault’s existence.
Such scenarios are common in earthquake-prone regions. For instance, a discovered fault beneath a new school site downtown led to part of the school being demolished and the area being converted into a park. Similar actions have been taken at Los Angeles Southwest College, San Bernardino Valley College, and a Huntington Beach shopping center. In Signal Hill, developers avoided building homes over a fault, opting instead for roads and recreational facilities.
According to the state Earthquake Authority, California has more than 500 active earthquake faults. The Greater Los Angeles area alone contains numerous smaller faults beyond the well-known San Andreas and Puente Hills faults, including the Northridge, Raymond, Santa Monica, Hollywood, Newport-Inglewood, San Jacinto, and Elsinore faults, all of which have caused significant damage historically.
Local Concerns and Regulations
California generally bans new construction on active faults, yet there are no statewide mandates for existing buildings located on these faults. Many cities prioritize retrofitting vulnerable buildings to withstand earthquakes, rather than focusing solely on fault lines. Cities like Los Angeles, San Francisco, and Berkeley require seismic retrofits for structures at risk of collapsing during a major quake. Other cities provide voluntary guidelines for building owners.
Buildings distant from faults can still be at risk due to the widespread impact of seismic waves.
Risk to Existing Buildings
While California restricts new construction on faults, uniform regulations for existing buildings are lacking. Local governments and building owners bear the responsibility for ensuring public safety. Avoiding construction over active faults is prudent, but it’s also crucial to address the vulnerabilities of older buildings, especially those built before the early 1980s.
To assess the risks to your building, consider a complimentary evaluation from Optimum Seismic. Visit OptimumSeismic.com or call 833-978-7664 for more information.
The safety of your building ultimately depends on proactive measures taken today.
