Los Angeles Mandates Fault Surveys in Risky Areas

According to a new rule, developers building over known faults will need to drill or take samples to find the rift's exact position. While it slows down construction, the measure might prevent catastrophic future quake damage.

1 minute read

August 7, 2015, 11:00 AM PDT

By Philip Rojc @PhilipRojc


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Drought resilience may be a hot topic these days in Southern California, but that doesn't mean an old threat has vanished. A new rule in Los Angeles stipulates that "developers looking to build a new structure in [earthquake risk] spots must first prove they won't be doing so on top of a dangerous fault, according to Ashley Atkinson with Mayor Eric Garcetti's Office."

The rule only applies to faults already mapped by the California Geological Survey. However, "the state doesn't have the funds it would need to map every potentially dangerous fault, leaving a number of well-known faults unmapped, including several in Los Angeles."

This safety measure may put a damper on some projects, but shouldn't prove too difficult a hurdle. From the article: "The new rules will likely slow down some future projects since digging to look for a fault — or 'trenching' as it's known — is time-consuming and can cost tens of thousands of dollars. However, some developers might be able to provide enough evidence by drilling for core samples, Atkinson explained, which is a less involved process."

Friday, July 17, 2015 in KPCC

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