Volcano Watch — More tips for surviving the next big quake

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The magnitude-5.2 earthquake that occurred at 12:02 a.m. Tuesday morning served as a not-so-gentle reminder of the seismic hazard on the Island of Hawai‘i. The quake was felt throughout the State, with reports from as far away as Kapa'a, Kaua‘i. 
 

The magnitude-5.2 earthquake that occurred at 12:02 a.m. Tuesday morning served as a not-so-gentle reminder of the seismic hazard on the Island of Hawai‘i. The quake was felt throughout the State, with reports from as far away as Kapa'a, Kaua‘i. 

There was relatively minor damage reported following this week’s earthquake, but future, larger earthquakeswill almost certainly be more destructive. There are many things you can do to reduce your risk. Last week, Harry Kim and the staff at the County Civil Defense Agency wrote the “Volcano Watch” and provided you with some ways to prepare for the next big earthquake here. To provide further suggestions about how you can reduce damage from an earthquake, we asked Virginia Macdonald, an architect in Volcano, to provide you with her perspective. She begins with a story . . .

“Wherever you are, Irv, I wanted you to know that if you have gone from this earth, I hope heaven has a special little house for you with shear walls and vertical straps. And I'm sorry I called you a dirty dog-licking, rat brained, fish-eyed son of a scabby harlot. I get a little emotional when it comes to spending money. But I'll be ever grateful to you, Irv. The house stands. We owe you for that. Come on over, the Bud's still cold."

So wrote a happy Los Angeles homeowner a few days after the recent 6.6 earthquake. Writer Al Martinez of the L.A. Times used his column to thank his building inspector, Irv Erickson, for insisting that the house Al Martinez was building in 1978 be done right.

Irv came to the columnist's mind as he stood in his house the morning after the six-point-sixer, when it dawned on him that the worst damage to his house was things dumped on the floor. Nothing cracked or split or shattered, and the place remained firmly on its foundation. There is no question in my mind that all that is due to Irv, the L.A. building inspector.

On the Big Island, there was a big rush last fall as people tried to get a building permit before the more protective 1991 Building Code took effect November 8. Other folks still try to ask their building inspector to ”kokua" and look the other way rather than to enforce the Building Code.

It is true that not many buildings have been totally destroyed by earthquakes or high wind on the Big Island. Adherence to Code would prevent much damage, even in a hurricane like ‘Iniki or from the larger earthquakes that occur periodically on this island.

Let's look first at damage and injury within a building and then at the building itself. My first experience with our own Hawai‘i Island 6.6 - that's a Richter six-point-sixer - was the 1983 quake, which was centered near the Volcano area. We were in the old Macdonald house on Golf Links Road, and I never thought I'd get out alive. The house, although damaged, did survive, but more than half of my china, stemware, precious 33 LP records, and other valuables were ruined. Good furniture was scarred by flying objects. The carpet was ruined by blood from our cut feet as we escaped shoeless through the broken glass.

Much of such non-structural damage can be prevented. Here is a checklist of suggestions on prevention:

Using metal tubing, heavy metal strapping, and lag bolts, secure the water heater to the studs in the wall. If you have propane, secure the propane tank, and know where and how to turn off the gas. These steps could prevent a fire, as well as water damage.

Know where, and how, to turn off the water supply from a catchment tank. This will keep you from losing your water supply. The line from the tank to the house almost always breaks. The water tank should be ferrous cement or, at least, be secured to the ground so that it will not tip over.

Put latches, like those used for baby-proofing, on all cabinet doors and on drawers to keep the contents from flying out. Bolt cooking stoves, wood stoves, and other heavy appliances to the floor to prevent their moving. A wood stove may move only a few inches, but the shifting may crack the chimney and require an expensive replacement. Lights on long chains can become swinging instruments of destruction. Shorten the chains or move the fixtures farther away from windows or walls.

Add a rim about one inch high at the front edge of open shelves to prevent things from hop-hop-hopping off. Set heavy shelf or cabinet-top-items as far back from the edge as possible. In our present house, we have white golf tees in holes drilled into one open display shelf around a valuable antique fish platter. The heirloom is safe, and the golf tees hardly show.

Do not place heavy things, such as a large TV, on a high surface, or if it must be there, secure it. One friend at Volcano might have been injured by a falling TV set had she not moved a few seconds before the 1983 quake hit. Do not place the head of your bed under a heavy wall mirror, which could come crashing down.

Now, to the building itself. Even when a house does not come completely apart in an earthquake, it may have sloping floors, cracked walls, doors that don't work, weakened joints, plumbing pipes that leak, and electrical wires which have been rubbed by the violent motion. In California, buildings with this kind of partial damage were finished off by the aftershocks. The wires rubbed bare in places might eventually cause a fire of “unknown origin."

A secure load-path from the ground to the roof is needed. This means that each element of the structure must be securely fastened to the connecting elements. Properly applied metal connectors are recommended to unify this load path. The Simpson Strong-Tie Catalogue dated 1991 has anchors and tie-downs for both new construction and retrofitting. Research has shown that, during earthquakes and high winds, wooden buildings reinforced with metal connectors outperform those buildings that remain unreinforced. Other companies also manufacture engineered connectors.

In theory, this unified load-path from ridge to ground for earthquake- and hurricane-proofing is easy to understand, but its proper application to any particular building usually requires professional help from an architect or a structural engineer.

A four-year-old may think stacking up blocks on a card table, shaking the table, and watching the blocks fall down is fun. Watching a real house fall down is not.

For one source of help, the American Institute of Architects (AIA) on the Big Island suggests a booklet published by the California Seismic Safety Commission entitled "The Homeowner's Guide to Earthquake Safety." These booklets will shortly be available at the public libraries and at cost ($3) at the offices of the following AIA Architects (see yellow pages for addresses): Taylor Cockerham in Hilo, Aza Summers in Waimea, Virginia Macdonald in Volcano, and Jack Parazette in Kona. 

On page 2, the booklet states, "Taking precautions such as strengthening your home can reduce the risk of earthquake damage. There are no guarantees of safety during earthquakes, but precautions can help. The Seismic Safety Commission hopes that you will act on the suggestions outlined in this booklet and make yourself, your family and your home safer before the next damaging earthquake."

The booklet covers the following problems: unbraced water heaters, foundations not anchored, weak, crippled walls, post and pier foundations, unreinforced masonry foundations, houses on tall walls or posts, unreinforced masonry walls, and living areas over garage. These weaknesses are addressed individually and solutions proposed. It is illustrated with a number of drawings.

Earthquakes are a reality on this volcanically and seismically active island. If your home is poorly built, you may have been all right so far, but don't count on it in the future. Prevention is less expensive than reconstruction. Peace of mind in earthquake country is invaluable and possible.