Millions saved in Japan by good engineering and government building codes

As the devastation in Japan achingly unfolds, it’s easy to learn about the thousands of deaths, the piles of debris, the washed-away homes and think, “Nothing could be worse.”

But that’s not the case.

Of course, the toll is both enormous and tragic. Thousands are dead. Economists estimate the economic losses between $50 billion and $150 billion. (Insurance losses will be less, since not everything that gets damaged is insured.)

It could have been so much worse. The building codes and warning programs in place saved thousands of people and billions of dollars.

Japan enjoys some of the world’s strongest building codes to minimize the earthquake threat and has continued to strengthen them after each event.   The New York Times examined the issue shortly after the earthquake:

In Japan, where earthquakes are far more common than they are in the United States, the building codes have long been much more stringent on specific matters like how much a building may sway during a quake.

After the Kobe earthquake in 1995, which killed about 6,000 people and injured 26,000, Japan also put enormous resources into new research on protecting structures, as well as retrofitting the country’s older and more vulnerable structures. Japan has spent billions of dollars developing the most advanced technology against earthquakes and tsunamis.

Japan has gone much further than the United States in outfitting new buildings with advanced devices called base isolation pads and energy dissipation units to dampen the ground’s shaking during an earthquake.

The isolation devices are essentially giant rubber-and-steel pads that are installed at the very bottom of the excavation for a building, which then simply sits on top of the pads. The dissipation units are built into a building’s structural skeleton. They are hydraulic cylinders that elongate and contract as the building sways, sapping the motion of energy.

The Times article, written last week, also emphasized tsunami protections like regular training drills and sea walls. The swamping of Sendai makes it unclear how well those worked, but in some cases, the tsunami moved so rapidly, people had little chance to escape.

In some towns, the first waves struck within a half-hour of the earthquake, as this Wikipedia entry documents. And one standard piece of advice – get above the wave – didn’t work in towns where the high point was a building that washed away.

But the building codes seem to have done their job in the face of the largest earthquake in Japan’s long history. Although the damage is extensive, it is a far cry from the destruction last year in Haiti, where poor construction increased the death toll. The country also fared better than China did after the Sichuan earthquake in 2008. There, building codes were strong, but enforcement was lax.

Even with the post-Kobe improvements, there will be a lot of lessons coming from this month’s earthquakes, including how to protect nuclear reactors from the twin threats of earthquake and tsunami.

In the United States, the insurance industry makes sure building codes are enforced through the Building Codes Effectiveness Grading System, a job performed by the Insurance Services Office. The system got its start after Hurricane Andrew in 1992, when it became clear that Miami’s vaunted hurricane codes were spottily enforced. Buildings in highly rated areas are eligible for insurance discounts.

Meanwhile, Reuters notes that in California, newer buildings can withstand mighty quakes, but if one happens, “the surviving buildings will tower over a carpet of rubble from older structures that have collapsed.” The issue, according to Reuters: California has been lax in retrofitting older buildings.

Retrofitting was also an issue in the recent New Zealand earthquake. Recall most of the startling images – the steeple toppled from Christchurch Cathedral, for example – were older buildings in need of retrofit. In 2004, New Zealand authorities required old buildings to have one-third of the resilience of newer ones, but gave the requirement 20 years to take effect, the Wall Street Journal reported early this month.

I.I.I. continues to update its web page covering the Japan quake.

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