Editorial: Earthquakes are equal-opportunity destroyers

The 7.8 magnitude earthquake that shook San Francisco in 1906 killed an estimated 3,000 people, destroyed 80% of the city and turned the West Coast’s largest and most sophisticated community into a virtual shanty town of tents and camps for the 225,000 left homeless. The city was rebuilt, but people and commerce headed south to Los Angeles, which grew significantly in the decade following the earthquake — because of that earthquake.

Today’s building codes might prevent destruction as catastrophic as what occurred in early 20^th century San Francisco. But the lesson here is that a substantial earthquake in one city also has an impact on other cities nearby.

Last year, the city of Los Angeles passed some of the most sweeping seismic retrofitting mandates in the country. It took decades to get politicians, property owners and tenant leaders together to support the same idea: that retrofitting buildings saves lives, preserves communities and is worth the cost.

Few other communities in Southern California are following suit, however. A survey by seismologist Lucy Jones, who had a formative hand in helping Los Angeles city officials craft their retrofitting ordinance, shows that fewer than 5% of the cities in six Southern California counties (San Diego County not included) have done anything about mandating retrofitting of the soft-story wood buildings that proliferate across California.

Not all cities need retrofitting. More recently incorporated cities typically have new buildings that were constructed after more stringent seismic safety requirements were put into state building codes. And the city of Downey was way ahead of the curve, having adopted a mandatory retrofit law for pre-1957 buildings years ago.

Even though the last two decades (since the 6.7 quake in Northridge) have been relatively quiet on the temblor front, surveys of quakes and the patterns of their occurrence indicate what everyone who has lived in Southern California has been already told: an earthquake at least as strong as Northridge will happen one day, probably on the southern end of the San Andreas fault, and in preparation buildings should be retrofitted.

There are a variety of vulnerable types of buildings. The concrete and so-called soft-story wood buildings built before the late 1970s require retrofitting to prevent them from collapsing. And steel frame buildings built more than 20 years ago need to be examined to find out if previous quakes had cracked any of their welds and weakened them.

The best way to start approaching the problem is for cities to take an inventory of their potentially vulnerable buildings. Several cities in L.A. County have this work underway, including Los Angeles, West Hollywood and Santa Monica. The next step after that is to require the owners of vulnerable buildings to retrofit them. The West Hollywood city council is expected to consider a mandatory retrofit ordinance in January; The Santa Monica City Council is expected to begin discussing a proposed wide-ranging retrofitting program at a meeting Tuesday, and Beverly Hills is considering an initial mandate for soft-story wood buildings.

All these cities should put ordinances into effect as soon as possible. One obvious challenge is that retrofitting can be expensive business. The city of L.A. was smart enough to pass a companion ordinance allowing owners of rent-controlled apartment buildings to pass on 50% of the cost to tenants, but with a ceiling on the annual increase in rent. Both Santa Monica and West Hollywood want to pass their ordinances before making a decision on how costs should be split. The issue may be moot in Beverly Hills, where the city has already allowed annual increases in rent-controlled apartments that should be large enough to cover the costs of retrofitting.

Whatever these cities decide, the burden should not fall entirely on renters. Although renters benefit from safer dwellings, property owners ultimately profit from the increase in property value tied to the seismic upgrades. The deal that the L.A. City Council made to split costs and have ceilings on increases was something that both property owners and tenants associations considered an acceptable compromise.

The least cities should do is make an inventory of buildings that appear to be at risk and require property owners to evaluate their buildings for their vulnerability to an earthquake. Some will be fine. Others will need work. But this is the starting point.

A major temblor within the San Andreas fault will be an equal-opportunity destroyer. Every city in the area needs to be as prepared as possible.

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