4.6: Preparing for the Next Earthquake
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)“In its relation to man, an earthquake is a cause. In its relation to the Earth, it is chiefly an incidental effect of an incidental effect.”
K. Gilbert, 1912,
preface to U.S. Geological Survey Professional Paper 69
1. Introduction
We are in denial about earthquakes. During the past fifteen years, scientists have reached a consensus that great earthquakes have struck the Pacific Northwest, and more will arrive in the near future. Government has responded by upgrading construction standards and establishing an infrastructure of emergency services down to the county level. Media reports take it as a given that there will be future damaging earthquakes.
Yet if the average person were to list the top ten concerns in his or her daily life, earthquakes probably would not make the list, not even in California.
In terms of public perception, earthquakes might not be all that different from other disasters such as floods or wildfires. Television reports show expensive homes burned out by forest fires, or homes flooded out in the Willamette Valley, but since people own the land on which their former homes stood, they tend to rebuild in the same place, if local government will let them. In new suburbs of Seattle and Portland, some are opposed to laws restricting building next to an active fault or landslide. Nobody seems to learn anything.
There’s the story about sheep grazing at the edge of a field. A wolf comes out of the forest, grabs a sheep, and carries it off. The other sheep scatter and bleat for a few minutes, then continue their grazing. The forest is still there, and the wolf will come back, but the sheep graze on.
So it is with earthquakes. The Scotts Mills Earthquake struck in 1993, a flurry of excitement followed, and newspaper editorials referred to the earthquake as a wake-up call (see the Oregonian by Jack Ohman cartoon at the beginning of the book). A person living in Vancouver, Everett, or Eugene—cities not struck by a damaging earthquake during the time people have been keeping records—simply doesn’t believe earthquakes are a problem. Local elected officials don’t believe it either. The Nisqually Earthquake was a major story in early 2001, but no great urban earthquake has struck since then, and Oregon got off scot free. Earthquakes have dropped out of the news, and most people have forgotten about them.
It is in light of such public apathy that this chapter is written. You try to organize your household, your neighborhood, and your children’s schools, but your efforts might result in your being called Chicken Little, warning that the sky is falling. If you’re serious, you must be determined and patient and have a thick skin. It won’t be easy.
2. Getting Your Home Ready
Chapter 11 focused on steps you can take to make your home and its contents more resistant to earthquake damage. This chapter presents ways you can prepare yourself and members of your family to survive an earthquake and to help others survive as well. It’s analogous to the fire drills in school or aboard an oceangoing ship. We’re pretty sure our school or the ship will not catch fire, but we conduct the fire drills all the same. Fire drills are built into our culture. Earthquake drills are conducted in most schools, but they are often not taken seriously—even by the school officials who conduct them
What can happen to your house in an earthquake? Shaking could cause a chimney to collapse, plate-glass windows to break, tall pieces of furniture to fall over, or a garage to cave in. Liquefaction or landsliding beneath your foundation could cause your house to move downslope, breaking up as it does so, and snapping underground utility lines. This happened in the Marina District of San Francisco in 1989 and in parts of the San Fernando Valley in 1994. A severe winter storm might result in dozens of landslides, but a large earthquake might result in thousands, some more than a mile across. If you live on the coast, your house might be in danger of a tsunami, in which case you have only a few minutes to get to high ground, above the tsunami run-up line.
Some steps outlined here are not unique to earthquakes. Many are the same steps you would take to survive a terrorist attack. They would apply if you were marooned by a flood or a landslide that cut off access to your house. But a large earthquake like Northridge or Loma Prieta differs in the large number of people impacted. The 9-1-1 emergency number would be overwhelmed and essentially useless, as it was in the earliest stages of the Nisqually Earthquake. You could lose your phone service, electric power, water, sewer, and gas for days or weeks. Police and ambulance services would be diverted to the most serious problems such as collapsed apartment buildings or major fires. Access to your house or from your house to the nearest hospital could be cut off by a damaged bridge or a major landslide.
For these reasons, be prepared to survive without assistance or any public utilities (gas, water, sewer, electric power, or phone service) for up to three days. If you are at work, or your children are at school when the earthquake strikes, you need to have a plan in place outlining what each member of the family should do. Designate a contact person outside the potential disaster area that everyone should contact if your family is separated.
Prepare an inventory of your household possessions and keep it away from your house, in a safe deposit box or with your contact person outside your area. This inventory will come in handy when you submit your insurance claim (Chapter 10).
3. Earthquake Preparedness Kit
Designate a kitchen cabinet or part of a hall closet in your house as the location of an earthquake preparedness kit. Everyone should know where it is and what’s in it. Make it easy to reach in a damaged house. (The crawl space in your basement is not good, especially if you haven’t reinforced your cripple wall.) The kitchen is okay, and so is an unused and cleaned-out garbage can in your garage—unless the garage is prone to collapse due to “soft-story” problems. Many items listed below are handy in any emergency—not just an earthquake. (Maybe you are already doing this as your part of the war on terrorism.)
- First-aid kit, fully equipped, including an instruction manual. Check expiration dates of medicines and replace when necessary. Liquids and glass bottles should be sealed in zip-loc storage bags. Keep your previous prescription glasses here; your prescription might have changed, but the glasses will do in an emergency.
- Flashlights, one per person, preferably with alkaline batteries. Replace batteries every year, following a schedule. Keep extra batteries in the package they came in until ready for use. Several large candles for each room, together with matches. Coleman lantern, with an extra can of gas for it.
- Portable radio with spare batteries. If the power is off, this will be your only source of information about what’s going on. Your portable phone won’t work if your phone service is cut off. Your cell phone might work, but heavy phone traffic could make it hard to get through, as was the case during the Nisqually Earthquake, the first “cell-phone earthquake.” It may be more difficult to call locally than to call long distance.
- Food, in large part what you would take on a camping trip. Granola bars, unsalted nuts, trail mix, and lots of canned goods (fish, fruit, juice, chili, beef stew, beans, spaghetti). Dried fruit, peanut butter, honey (in plastic containers, not glass), powdered or canned milk. We’re talking about survival, not gourmet dining, but try to stock with food your family likes. Keep a manual can opener and other cooking and eating utensils separate from those you use every day. If you lose power, eat the food in your freezer first. It will keep for several days if the freezer door is kept shut as much as possible.
- Fire extinguishers. Keep one in the bedroom, one in the kitchen, and one in the garage. Attach them firmly to wall studs so they don’t shake off. Keep a bucket of sand near your fireplace during the winter, when the fireplace is in frequent use.
- Drinking water. You’ll need one gallon per person per day for at least three days; more is better. Large plastic containers can be filled with water and stored; change the water once a year. Two-and-one-half-gallon containers are available, but one-gallon containers are easier to carry. Your water heater and toilet tank are water sources, but if the water heater is not strapped and falls over, its glass lining may break, requiring the water to be filtered through a cloth. Empty the water heater by turning off the heater (remove its fuse or shut off its circuit breaker) and its hot-water source, then turn on a hot water faucet and fill containers. Water purification will be necessary. Do not use toilet tank water if the water has been chemically treated to keep the bowl clean (turns blue after flushing). Swimming pool or hot tub water is okay for washing but not for drinking.Turn off your house water supply at the street to keep sewage from backing up into your water system. Plug bathtub and sink drains.If you’re a backpacker or you travel in underdeveloped countries, you already know about hand-operated water pumps, filters, and purifying tablets, available at outdoor stores like REI. Iodine purifying tablets make the water taste terrible, but you can add other tablets to neutralize the taste. Store these with your preparedness kit, and use them if there is any doubt about the water, including water from the water heater or toilet tank. You can also use liquid bleach in a plastic container, but do not use granular bleach!
- Tools. Keep a hammer, axe, screwdriver, pliers, crowbar, shovel, and Swiss Army knife in your kit, along with work gloves and duct tape. Buy a special wrench to turn off the gas at the source. Keep this at the gas valve, and make sure everyone knows where it is and how to use it. If you smell gas, turn your gas supply off immediately (Figure 11-7); the pilot light on your furnace would be enough to catch your house on fire. Don’t turn it on again yourself—let a professional do it. Keep a wrench at the water meter to shut off your water at the source.If your water is shut off, you won’t be able to use the bathroom. Use your shovel to dig a hole in your yard for a temporary latrine. Line the hole with a large plastic garbage bag; alternatively, sprinkle with lime after each use (purchase the lime from a hardware store). If you are able to get to your bathroom, you could line the toilet with a small garbage bag, use the toilet, and dispose of the bag.
- Camping gear. Keep in one place tents, sleeping bags, tarps, mattresses, ponchos, Coleman stoves and lanterns, and gas to supply them so they are as accessible as your preparedness kit. Picnic plates and cups, plastic spoons, paper napkins, and paper towels should be in your kit.
- Other items. Large, zip-loc plastic bags; large and intermediate-size garbage bags with twist ties; toothbrushes and toothpaste; soap; shampoo; face cloths; towels; dish pan and pot; toilet paper; sanitary napkins; shaving items (your electric razor won’t work); baby needs; and special medications (especially for elderly people).
- Kits for elsewhere. Under your bed, keep a day pack with a flashlight, shoes, work gloves, glasses, car and house keys, and clothes for an emergency. Keep another day pack, along with a fire extinguisher, in the trunk of your car and—if you work in an isolated area—at your workplace.
4. Other Preparations
After a major earthquake, civil authorities will inspect your neighborhood to see whether damage has occurred, and they might determine that your house is dangerous to live in. This is due to fear that the structure might collapse with you inside. If your house is labeled with a red tag, you will not be permitted to live in it, and the house will have to be torn down. If your house is labeled with a yellow tag, you will be ordered to leave and will not be allowed to return until the necessary repairs are made, and your house is determined to be safe to live in. Accordingly, you should have ready those items you need if you are forced to leave your home for an extended period of time.
It’s nice to have a first-aid kit, but make sure that you and your family know how to use it. Take a first-aid course and a CPR class (there are lots of reasons to do this, not just earthquake preparedness). You might be called on to help your neighbor, and access to a hospital may be blocked.
5. Neighborhood Plan
Many neighborhoods already have a “neighborhood watch” plan for security. Arrange a meeting once a year to discuss contingency plans in case of an earthquake. Are some of your neighbors handicapped or elderly? Are there small children? Do some of your neighbors have special skills? There are advantages to having a plumber, carpenter, nurse, or doctor for a neighbor. Do each of you know where your neighbors’ gas shut-off valves are located? Be prepared to pool your resources. You can make lifelong friends during a major calamity. Your county or city emergency services coordinator, police department, and Red Cross office will be glad to help you get organized.
The Humboldt County, California, Office of Emergency Services (707-268-2500) has information on forming a Neighborhood Emergency Service Team (NEST) in your neighborhood. These groups of neighbors, members of local organizations, and employees of local businesses, headed by an elected NEST captain, are organized against any disaster—not just an earthquake. Seattle’s Community Emergency Response Team (CERT) has established more than three hundred and sixty neighborhood teams serving twenty-five thousand city residents. The city of Bellevue has similar neighborhood organizations with team captains; these meet several times per year.
6. Your Child’s School and Other Buildings You Use
Damaged school buildings were the impetus for the first California law upgrading building standards—the Field Act of 1933. Oregon and Washington waited until after the general building code upgrade of the mid-1970s. Since then, major school retrofit programs have begun in Seattle, Portland, Eugene, and Corvallis, generally funded by bond issues and addressing other needs besides earthquakes, such as antiquated furnace systems. There are still many communities where these measures have not been started; bond issues to upgrade schools continue to fail.
Your school can take steps that cost little or no money, only time. Work through the PTA to ensure that the school has its own earthquake-preparedness supplies, an evacuation plan, and earthquake drills. School officials may not take earthquake drills seriously. Ask questions about the specifics of staff training and responsibilities. What is the school’s plan to release children (or to house them in the school building) after an earthquake? Are hazardous materials stored properly? Are there heavy bookcases that might topple on children at their desks (Figure 11-10) or light fixtures that might come down on top of them (Figure 12-7)? The Seattle Public Schools, through Project Impact, implemented a program to remove overhead hazards, install automatic gas shutoff valves, and organize site teams to improve classroom safety, including teachers, support staff, parents, and volunteers. These improvements greatly limited property damage in the 2001 Nisqually Earthquake.
Earthquakes seem to pick on universities. The 1989 Loma Prieta Earthquake caused more than $160 million in damage to Stanford University, including the building housing the Department of Geology. The university had previously been damaged severely by the 1906 San Francisco Earthquake; at that time it was a relatively new campus. The 1994 Northridge Earthquake trashed California State University at Northridge—again including the Department of Geology, which was still in temporary quarters two years later. The University of California at Berkeley is crossed by the Hayward Fault and is at risk from a M 7 earthquake in the near future. Seismic retrofit programs have been underway since 1978, with the expenditure of $250 million, but more than one-fourth of usable campus space is labeled “poor” or “very poor” in terms of earthquake resistance. Retrofitting these unsafe buildings over a period of twenty to thirty years will cost at least $1.2 billion. The University of Washington campus is built on glacial till overlying thick sedimentary deposits of the Seattle Basin, possibly amplifying earthquake waves from a subduction-zone earthquake or an earthquake on the Seattle Fault. Portland State University is close to the active Portland Hills Fault.
Let’s pray that the earthquake doesn’t strike on a Sunday morning. The Nisqually Earthquake shook loose two of four spires towering over the First Baptist Church on Capitol Hill in Seattle; one of these spires weighed nine thousand pounds. Many cities have large church buildings constructed of unreinforced masonry. In most cases, the churches do not have earthquake insurance, nor do they have the money to bring their buildings up to code.
And how about those historic courthouses, built of unreinforced masonry in the nineteenth century? Lovely to look at, but dangerous to work in. The Klamath County, Oregon, courthouse was rendered useless after an earthquake of M 6 in 1993, and the Grays Harbor, Washington, courthouse was severely damaged during the 1999 Satsop Earthquake. On the other hand, if the building is a structure of historical significance, funds might be made available to repair it.
7. During the Earthquake
The strong shaking will stop. For a M 6 to M 7 earthquake, strong shaking will last less than a minute—in most cases less than thirty seconds—but it might seem the longest minute of your life. A subduction-zone earthquake can produce strong shaking of one to four minutes, but it, too, will stop.
The earthquake mantra is duck, cover, and hold on. Duck under something such as a table or desk, and cover your face and neck with your arms. Hold on until the shaking stops. Teach this to your children, and make it part of your own family earthquake drill.
The greatest danger is something collapsing on you. So get under a big desk or table. Stay away from windows, chimneys, or tall pieces of furniture such as a refrigerator or china cabinet. Standing in a doorway is not a good option, unless you happen to live in an adobe house in a third-world country. The doorway might be in a wall that isn’t braced against shear, and both wall and doorway could collapse, sandwiching you in between. Do not run outside, because you might be hit by debris or glass falling from the building.
If you can’t get under something, sit or lie down with your feet and hands against a wall. Turn away from glass windows or mirrors. Don’t hold or pick up your dog or cat; it will be so confused that it might bite you. Stay where you are until the strong shaking stops. If a vase is about to topple from a table, don’t try to catch it.
Should you be at a stadium or theater, cover your head with your coat and stay where you are. Do not rush to the exits. The behavior of the California crowd when the Loma Prieta Earthquake struck at the beginning of the World Series game in October 1989 was exemplary. There was no panic, and people did not trample over others trying to get out of the ball park. There were no injuries. The important thing to remember is that there is no reason to leave. After the shaking stops, there will be plenty of time to head for the exits.
At work, get away from tall, heavy furniture (Figure 11-10) or get under your desk. The fire sprinklers might come on. Stand against an inside wall. If you’re in a tall building, do not try to use the elevator; it probably won’t work. If the lights go out, just stay where you are.
If you’re in a wheelchair, lock your wheels and stay where you are. If you’re out in the open, move only if you’re close to a building where debris could fall on you.
Should you be outside in a business district with tall buildings, get as far away as you can from the buildings, where plate glass could shatter and masonry parapets could come crashing down on you. Stay away from tall trees. Watch for downed power lines.
If you’re in your vehicle (with seat belt fastened), pull over to the side of the road. Do not stop under an overpass or on a bridge. Watch for places where sections of roadway might have dropped. Clarence Wayne Dean, a California Highway Patrol officer on his way to work on his motorcycle, was killed when he drove off the end of a freeway overpass that had collapsed from the Northridge Earthquake. If wires fall on your car, stay in your car, roll up the windows, and wait for someone to help you. You might be waiting a long time, but the alternative—electrocution—makes the wait a safer if more boring choice.
8. After the Earthquake
Look for fires in your own home and the homes of your neighbors. Look out for downed power lines. Has anyone been injured? Is your house damaged enough to require it to be evacuated? Consider your chimney as a threat to your life until you have assured yourself that it’s undamaged. Check for gas leaks, and if you smell gas, turn off the main gas valve to your house (Fig. 11-7), which will extinguish all your pilot lights.
In case of a fire, try to put it out with your fire extinguisher or your bucket of sand. The most likely place for a fire is your wood stove if it has turned over. You have a few minutes to put the fire out. If the fire gets away from you, get everybody out of the house.
An earthquake might cause electric and telephone lines to snap. Even if you have no power, do not touch any downed power lines.
This is not the time to get in your car and try to drive around town looking at the damage. Roads will be clogged, making life tough for emergency vehicles. Stay where you are and turn on your portable radio. You’ll be given status reports and told what to do and what not to do. If you’re told to evacuate your neighborhood, do so. You will be told where to go. Do not decide on your own that you can tough it out where you are. Lock your house, unless it’s too damaged to do so, to protect against looters.
9. Aftershocks or a Foreshock?
Crustal earthquakes and subduction-zone earthquakes have many aftershocks, and they will cause a lot of alarm. In a large earthquake, aftershocks will continue for months and even years after the main event. Many of these will be felt, and some can cause damage to already weakened buildings. This is one of the reasons you might be asked to leave your house. Though still standing after the main earthquake, it could be so weakened that it might not survive a large aftershock. Warn your family members that there will be aftershocks.
However, there is always the possibility that the earthquake you just experienced is a foreshock to an even larger one. The great 1857 Earthquake on the San Andreas Fault of M 7.9 was preceded by a foreshock of about M 6 at Parkfield. The Denali Earthquake of M 7.9 in central Alaska on November 3, 2002, was preceded eleven days earlier by a foreshock of M 6.7. The Chinese have based their successful earthquake predictions on foreshocks—in some cases many foreshocks. Normal-fault earthquakes, occurring in crustal regions that are being extended or pulled apart, such as the Basin and Range of Nevada, southeast Oregon, and eastern California, are more likely to have foreshocks.
10. Special Problems with Tsunamis
If you live on the coast, you will have the same problems everybody else has with shaking and unstable ground. But you’ll have an additional problem: the threat of inundation from a large wave from the ocean.
In the case of a distant tsunami, such as the one that originated in Alaska and struck Port Alberni, B.C., Seaside, Oregon, and Crescent City, California, in 1964, a warning will be issued by the Tsunami Warning Center in Alaska, including an expected arrival time of the tsunami. You will have time to evacuate to high ground. It’s critical that you have a portable radio turned on to listen for tsunami warning updates. Most of the people who got into trouble in the Easter weekend tsunami of 1964 were just enjoying a normal spring holiday, without enough concern for events in the rest of the world to keep up with the news. With satellite communication and tsunami warning centers throughout much of the Pacific, the warning of a distant tsunami should be taken seriously, but you have to have your radio on to hear it. A coastal community is well advised to have a siren to warn those who aren’t tuned in to their radio or television. This siren should be maintained by emergency-services or fire department personnel and should have its own generator.
In the case of an earthquake on the Cascadia Subduction Zone, you’ll have a much shorter time to react—twenty minutes or less. For this reason, if your area is subjected to very strong shaking lasting twenty seconds or more, don’t wait for a tsunami warning. Leave immediately for high ground and stay there for an hour or so until you’re sure there is no local tsunami.
There is no direct correlation between tsunami height and magnitude of the earthquake. A subduction-zone earthquake off the Pacific coast of Nicaragua on September 2, 1992 generated an unusually large tsunami for the size of the earthquake. It was found later that fault rupture was much closer to the surface, and fault motion took place much more slowly than for most subduction-zone earthquakes. In Papua New Guinea, coastal villagers were swept away by a tsunami generated by a landslide and by sea-floor deformation. Earthquakes like this are sometimes called tsunami earthquakes; the tsunami is much more extreme than the seismic shaking would predict.
The other problem in coping with tsunamis from a distant source is the period of the waves. Frequently, the first wave is not the largest one. The people of Crescent City, California found this out the hard way. The first and second waves were small and caused little damage and people returned to the shoreline, only to be struck by much larger waves that crashed through the town.
Unlike ordinary storm waves, the period of a tsunami wave can be as long as an hour. So when the first wave rushes up and then recedes, for the next half hour or so you will notice only the ordinary surf. But don’t think the tsunami is over. Wait at least two hours before you return. And, just as a tsunami rises higher than ordinary waves, causing great damage, the tsunami also causes the water to recede much farther out to sea, exposing ocean floor not ordinarily seen even at the lowest tides (Fig. 9-9). The temptation to rush to the beach at that time could be fatal.
11. Psychological Issues
Children are especially traumatized by earthquakes. Familiar surroundings—everything that is supposed to stay put in their lives—suddenly move, are damaged, or become a threat. Children might have to leave home for an extended period of time. They will fear that the shaking and destruction will get worse, or will happen again and again.
Assuring the physical safety of your child is only the first step. Include the child in all your activities, keep talking, and encourage the child to talk out fears. It might be necessary for your child to sleep with you for a few days until things return, more or less, to normal. Plenty of reassurance and just being present will help in overcoming your child’s fears after an earthquake. Encourage the school to plan group activities that relate to psychological recovery from an earthquake.
Elderly or disabled persons also might feel a sense of helplessness and fear due to an earthquake. Some individuals of any age are prone to “disaster syndrome.” This illness might not come on immediately after the disaster, but it builds up over days and weeks, with evidence of the disaster everywhere and with the telling and retelling of the stories of the event. In severe cases, these people will need counseling and might need to leave the area until they have recovered.
12. Leaders in Earthquake Mitigation:
Are You Ready To Step Forward?
I close this chapter with two people who are ordinary citizens, not earthquake scientists or engineers, but who took on the role of citizen leader.
The first is Diane Merten of Corvallis, a housewife with a large family, who began attending meetings at Oregon State University soon after the paradigm change recognizing the earthquake hazard facing the Northwest. Diane took it on herself to organize leaders in the city of Corvallis and in Benton County to prepare against earthquakes. This project was so successful that she was asked to lead other communities around the country in organizing themselves locally against disasters. Diane served as a citizen member of a committee appointed by the congressional Office of Technology Assessment evaluating the reauthorization of NEHRP.
The second is Roger Faris, a native of Seattle. In the early 1980s, Roger quit his general contracting business to develop a neighborhood home-remodeling cooperative in Phinney Ridge in Seattle. In the early 1990s, he met Brian Atwater, who told him about the earthquake dangers to the Northwest. When Project Impact started, Roger was the logical choice to develop a course in retrofitting homes against earthquakes. The course was taught regularly; the tuition is ten dollars. In 1999, he was honored by FEMA as Outstanding Citizen of the Year, an award he received in Washington in Hawaiian shirt and khaki pants. As Inés Pearce of Seattle’s Project Impact put it, Roger is “one of those 1960s holdouts—a granola-headed idealist who puts his talent into building community rather than personal profit.”
We need more contractors like Roger, who can help people who want to strengthen their homes against earthquakes.
Suggestions for Further Reading
American Red Cross. 1985. The emergency survival handbook. Available from your local Red Cross office.
Lafferty and Associates, Inc. 1989. Earthquake preparedness—for office, home, family, and community. Available from P.O. Box 1026, La Canada, CA 91012.
Morgan, L. 1993. Earthquake survival manual. Seattle: Epicenter Press. 160p.
National Science Teachers Association. 1988. Earthquakes: A teacher’s guide for K–6 grades. NSTA Publications, 1742 Connecticut Ave. NW, Washington, DC 20009.
Seismic Safety Commission. 1992. The Homeowner’s Guide to Earthquake Safety. SSC 92-01. 28p.
Yanev, P. 1974. Peace of Mind in Earthquake Country: How to Save your Home and Life. San Francisco: Chronicle Books.