“A powerful 6.9 earthquake shook San Francisco for a minimum of ten consecutive seconds during the Game 3 warm-up. Some 12,000 homes were wrecked beyond habitability. Natural gas lines ruptured and set fires to buildings in the Marina district. A 1.25 mile-long stretch of The Cypress Street Viaduct, a major twin-decker roadway, collapsed on itself and killed 42 motorists in a single blow. In all, 63 people died and nearly 4,000 were injured.” Source
According to the Website for Budding Seismologists at Michigan Tech, “Most of the hazards to people come from man-made structures themselves and the shaking they receive from the earthquake.” The highest risks of injury to persons and property result from the 1. Ground shaking (causing building collapse, debris, and liquefaction if soil mixes with groundwater) 2. Ground displacement, 3. Flooding due to a broken dam or levee, and 4. Fires (from broken gas lines, electrical wires)
If you reside on the west coast, or anywhere in a seismic zone, chances are there are building codes to withstand earthquakes and perhaps a retrofitting program for some of the older and more susceptible structures. Entire engineering disciplines are devoted to the science of designing and building structures to withstand one of nature’s most unpredictable forces. You can visit Earthquake Engineering Research Institute here
These engineers have really cool toys too, for example the awesome shake table on page four of this 2006 paper by The Consortium of Universities for Research in Earthquake Engineering.
The National Earthquake Hazards Reduction Program (NEHRP)
The NEHRP was established by Congress in 1977 to reduce the risks that result from earthquakes. Since the Organization was first established, four agencies have taken a role in the mission of the NEHRP; Federal Emergency Management Agency (FEMA), United States Geological Survey (USGS), The National Institute of Standards and Technology (NIST, actually the lead agency), and the National Science Foundation (NSF).
For a fascinating discussion surrounding the creation of the NEHRP, visit the GeoTimes 2003 article by Robert M. Hamilton, Milestones in Earthquake Research.
Preparing for “the Quake”
Just for fun, take a minute and look at how close you are to a fault line, and the risk of an earthquake in your community. Based on the risk of seismic activity in your area, there are several FEMA grants available to the state level, with funding authorized (as of this writing) for mitigation activities such as infrastructure inspections and to update codes and ordinances. A list of state contacts for this program can be found here.
For another excellent article on preparing buildings for earthquakes, with movies, animation, and a science project you can do at home (on liquefaction) visit the Exploratorium. This one is actually really great for kids.
Code Resources for Shakeproofing; New Construction and Retrofitting
Guidance for Building Codes in Earthquake “zones” through FEMA are developed“to encourage design and construction practices that address the earthquake hazard and minimize the resulting risk to life and property.” An important note is that enforcement is not a direct requirement for these guidelines. State and local enforcement guidelines should be developed and followed. Several resources are available from the FEMA library, “Earthquake-Resistant Design Concepts: An Introduction to the NEHRP Recommended Seismic Provisions for New Buildings and Other Structures” Can be downloaded or ordered from FEMA, and the Prestandard and Commentary for the Seismic Rehabilitation of Buildings can be found in the FEMA library, “Seismic retrofitting of vulnerable structures is critical to reducing risk. It is important for protecting the lives and assets of building occupants and the continuity of their work. On the whole, communities with more retrofitted structures can recover from earthquakes more rapidly.”
Other Resources
Earthquake Grants
Some ideas for local risk reduction programs are available on the FEMA website as well,
“FEMA maintains the online Mitigation Best Practices Portfolio to document and share examples of successful mitigation activities. Many of the varied projects described in the portfolio were or could have been funded through the earthquake-relevant assistance programs described on this page. Consequently, the portfolio can serve as a fertile source of ideas for earthquake risk-reduction projects that may be eligible for assistance under these programs.”(emphasis mine)
For more information, including toolkits for planning and building codes.
The “Quake Smart” toolkit, risk mitigation information for businesses.
This June 2007 Article by Jeff Wise, in Popular Mechanics provides photos and schematics on the Bay Bridge in San Francisco, California.
And if you happen to live or work near federally owned buildings, the “GSA manages the development of national policies and standards for seismic/structural safety in federal buildings. We collaborate with private standard setting organizations, code bodies and professional associations to accomplish this.”
For real- time feeds on earthquake activity around the globe, you can sign up on the USGS page here.
