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Amajor earthquake can leave hundredsor thousands of people dead or in-

jured and homeless; hospitals toobadly damaged to receive victims; electrici-

ty, water, and gas outof service; trans-

portation damaged;and fires raging.Even in Japan and

California, where earthquake-resistant con-struction practices have been in effect fordecades, loss estimates are staggering. Amagnitude 6.7 (M6.7) earthquake on theHayward fault near San Francisco (to whichexperts have assigned a one-in-four chanceof occurring by 2031) (1) is projected tocost 3000 to 8000 lives and $170 to $225

billion in direct losses. A repeat of the M8Kanto earthquake (Tokyo, 1923) could cost60,000 lives and over $2 trillion in total eco-nomic losses (2). The Federal EmergencyManagement Agency (3) has estimated thatdirect losses from earthquakes in the UnitedStates are at least $4.4 billion annually.

Much can be done to mitigate urbanearthquake risk. Accurate urban earthquakehazard maps, development of seismic de-sign provisions and adoption of appropriate

building codes, design of new structuralsystems, rehabilitation of older structures,and the use of structural damping elementsand isolation have all contributed to im-

proved performance (see the figure).However, basic data and analysis are

lacking for how buildings and structuresperform under the extreme loads producedby earthquakes. Some experts think struc-tural damage prediction models are basedlargely on opinion (4). Application of labo-ratory data is difficult because of soil-structure interactions and difficulties simu-lating excitations at high frequencies. Theselimitations are increasingly important as

the postearthquake performance goal forcritical buildings moves toward immediateoccupancy and functionality (5).

Developing predictive models of structur-al response will require much more empiricaldata. Ground-motion recordings, from net-works of sensors for pressure, displacement,and strain, in regions of moderate-to-largeearthquakes are essential. Improved monitor-

ing would result in better predictive modelsand more effective allocation of resources,such as deciding which building types areeconomical to rehabilitate. Insights into build-ing responses should also foster developmentof cost-effective engineering solutions.

Two new U.S. government efforts directlyaddress the need for better understanding ofthe response of structures to earthquakes: TheAdvanced National Seismic System (ANSS),an initiative by the U.S. Geological Survey to

broadly modernize and expand seismic mon-itoring, would place up to 6000 strong-ground-motion recording stations in U.S. ur-

ban areas (6). The Network for EarthquakeEngineering Simulation (NEES) is a distrib-

uted facility and communications infrastruc-ture for earthquake engineering being devel-oped by the National Science Foundation.

NEES provides new tools for modeling, sim-ulation, and visualization of response. Interestin the expansion of these programs was ex-

pressed during congressional hearings onreauthorization of the National EarthquakeHazards Reduction Program (NEHRP) in2003. A plan developed by the EarthquakeEngineering Research Institute calls for morethan doubling funds for each of the NEHRPagencies (7). Yet in its first 4 years, ANSS has

been funded at about 1/10th its authorizedlevel, and NEES proposed 2005 researchfunding is 1/5th the recommended level (5).

In contrast, after the 1995 M7 earthquakein Kobe (8), Japan increased funding forearthquake monitoring and research to $1

billion. Despite comparable size and earth-quake risk, Japan has more than 10 times thenumber of strong-ground-motion recordingstations as California and has implemented anational earthquake warning system.

Earthquake-resistant construction andstructural monitoring can be linked to betterhomeland security. A study of OklahomaCitys Alfred P. Murrah Federal Building af-ter its 1995 bombing suggests that physicaldamage would have been less if the designhad incorporated earthquake-resistant engi-neering (9). Modern seismic-monitoringsystems in structures could act as warningsystems, postevent indicators of damage,and sources of forensic information.

By 2010, the United States will investmore than $1 trillion in new buildings an-nually. Thus, a modest investment in exist-ing and proven technologies for earthquakemonitoring and engineering research shouldyield considerable benefits in future avoid-ed losses.

References and and Notes1. Working Group on Earthquake Probabilities, U.S.

Geological Survey (USGS) Open File Rep. 03-214(USGS, Washington, DC, 2003).

2. H. C.Shah, Disaster Res. No. 179(15 October 1995).3. Federal Emergency Management Agency (FEMA),

HAZUS 99 Estimated annualized earthquake lossesfor the United States(FEMA 366, FEMA,Washington,DC, 2001).

4. Testimony of L. Reaveley to the House ScienceCommittee, Subcommittee on Basic Research,NEHRPreauthorization hearings, 8 May 2003.

5. National Research Council, Preventing EarthquakeDisasters: The Grand Challenge in Earthquake Engineering(National Academies Press, Washington, DC, 2003).

6. Requirement for an Advanced National SeismicSystem, USGS Circular 1188; available at http://pubs.usgs.gov/circ/1999/c1188/.

7. Earthquake Engineering Research Institute (EERI),Securingsociety against catastrophic earthquake losses (EERI,Oakland, CA, 2003); available at www.eeri.org/cds_publications/research_plan_05-2003.pdf.

8. P. Somerville, Eos76, 49 (1995).9. FEMA, The Oklahoma City bombing: Improving

building performance through multi-hazard mitiga-tion (FEMA 277, FEMA, Washington, DC, 1996).

GEOLOGY

Building for EarthquakesWilliam Leith

POLICY FORUM

The author is with the U.S. Geological Survey, Reston,VA 20192. E-mail: wleith@usgs.gov

Enhanced online atwww.sciencemag.org/cgi/content/full/304/5677/1604

Earthquake engineering pays off. The OliveView Medical Center in California (top) washeavily damaged by the 1971 San Fernandoearthquake and subsequently razed. In 1994, anew, earthquake-resistant building there (bot-tom) received one of the highest accelerationsever recorded (2.3g) with only minor damage.

11 JUNE 2004 VOL 304 SCIENCE www.sciencemag.org