David Jacobson and Ross Stein report that the California Geological Survey released four preliminary Earthquake Fault Zone maps for parts of Los Angeles and Napa counties. The West Los Angeles coverage provides new active fault traces (where a fault intersects the surface) and zones (the areas in which some faulting could occur in an earthquake) for the Santa Monica Fault, the Hollywood Fault, and the Newport and Inglewood Fault. And the Hollywood Fault is responsible for lifting up one of L.A. most sacred landmarks, the Hollywood sign atop the Santa Monica Mountain range.
Because fault sections were added, revised, and removed, hundreds of billions of dollars of real estate are impacted by these new boundaries. This work is carried out under California law. If property lies within the Alquist-Priolo Earthquake Fault Zones that generally extend 150 meters to each side of a fault, special investigation is required prior to construction. These are preliminary review maps, which will not become official until at least January 11, 2018, but provide a chance to see what new fault research has revealed about the Hollywood, Santa Monica, and Newport-Inglewood Faults, which traverse a wealthy, densely-populated urban corridor. Alquist-Priolo Zones are defined as regulatory perimeters around active faults.
According to Tim Dawson, a senior engineering geologist for the California Geological Survey, these zones are intended to capture the most hazardous faults that could produce surface displacements of concern to a building. While a fault rupture can be confined to zones just a few meters (10 ft), because of the uncertainty of the fault location and the possibility of slip on a distributed band of faults, the state makes the zones 150 meters (500 ft) on either side of the mapped trace of a fault. If a property is within a Fault Zone, strict guidelines must be followed if new construction or major renovations are planned.
Managed & Built by I2M Consulting, LLC | © 2010-
