Alaska Earthquake Effects at Remote Cabin

Alaska is VERY seismically active.  At our place, we feel the earth shudder several times a year.  On November 30, South Central Alaska suffered a 7.2 earthquake, followed, in the ensuing month, by more than 6000 aftershocks, some of which were strong enough (above 5.0) to cause additional damage. 

Ceiling earthquake damage

At the time, we were out of state, so we nervously contacted friends in Anchorage and the Mat-Su Valley – on either side of the epicenter – to see how they fared.  One man said that everything on any shelf, wall, or mantle came crashing down, and his house is now riddled with cracks.  He was particularly devastated that his sons’ clay mementos, like their hospital footprints, had been smashed to smithereens.  A woman lost only one wine glass… and an entire 30 gallon aquarium (on carpet, of course!).  An acquaintance said that her home was fine but that her father’s house was totaled and he barely escaped when his two story stone fireplace buckled, smothering  the couch on which he had just been seated, seconds before.   The closest school to us – some 20 miles by air – is closed for the rest of the year.

Naturally, we were concerned  about the condition of our remote home, about 25 miles from the epicenter.  Had the log cabin fallen off its sonatube supports?  Had any of the guy wires supporting the power tower snapped, causing the collapse of the wind turbine, solar panels and various antennae?  I worried about my dozens of glass mason jars filled with our bees’ honey and the foods  I had so carefully seeded, grown, harvested, cooked, canned and stored.  Would I have that food to feed us through Alaska’s long winter, as planned, or would I encounter a shattered, frozen mess?

However, three weeks passed before we could survey the damage.  Because of the unseasonably warm autumn and early winter,  plus the succession of earthquakes, the ice on our lake (where we need to land by ski plane to get home) was dangerous.  Water had been thrust up through innumerable cracks in the ice, spreading out over the surface as overflow, and then knitting the ice slabs together in an ugly mess like Frankenstein’s bumpy stitches,  Pressure ridges added to the chaos.  This lumpy, bumpy, sandwich of ice/slush/water/ice/slush was also obscured by an 8 inch blanket of snow. A friend flew overhead to survey damage for us but could not tell much from the air.  Finally, we got home, thanks to one very experienced bush pilot and our only neighbor, who had roughed out an oval landing strip at his end of the lake.

After we landed and the pilot quickly departed to avoid overflow freezing to his plane skis, we walked gingerly across the shallows of the lake, in snowshoes, carefully stabbing the snow ahead of us with poles to ascertain conditions beneath the snow.  It was a relief when we reached the shore with shoes still dry.   As our buildings came into view, we saw that some tongue and groove ceiling planks had fallen from the upstairs deck, the 12 foot chimney on the outdoor evaporator stove (for syrup making) was awry, and logs in our woodcorral had tumbled forward, but otherwise, the structures appeared intact.  I unscrewed the pointy bear mat in front of the door and stepped into our home, which was as dark as a closet because of the plywood bear shutters covering the exterior of each window.  I slipped on the headlamp left by the front door, held my breath, and surveyed the room.

To my surprise and relief, my worries seemed unfounded.  The metal chimney of the wood stove was straight.  The clock and shelves were hanging in place.  The majority of books remained on the shelf and few drawers were open.  The only casualty appeared to be one mason jar that had fallen and rolled to the middle of the room.  What about the windows? I pulled back the curtains.  No discernible cracks.  What a relief! Could we spend the night in our own bed?

That decision awaited a test.  Was the two story chimney pipe plugged or bent?  Would it draw smoke well away from the roof or into the cabin through some crack in the seams?   We needed to check.  Bryan and I respectively watched the interior and exterior lengths of pipe for any errant smoke.  Eureka!  Time to load up the firebox and set on the stove pots with frozen water to humidify the air and feed us a warm soup in a few hours. 

From past winter returns, I knew that the interior temperature would rise from +10 F to  +32 F  in 3 hours, but above that, the incremental rise is a meager 3 degrees per hour, since the log walls themselves have to warm up, too.  I pitied Alaskans who had lost power during the earthquake without alternate heat sources like a wood stove or generator.  

Meanwhile, I shoveled paths to the weak, plywood outhouse and food shed, and then, with great trepidation, opened both doors.  The toilet shelf over the 5x5x5 hole was fine.  I was even more relieved to open the food shed door.  30 linear feet of shelves full of dozens of glass jars of food appeared unimpaired.  I bet I will discover cracks and leaks as temperature warm above freezing, but  I felt extremely relieved.  Plenty of food for winter.

Bryan checked the power shed and other than some spillage off shelves, all was well.

Why had we been so lucky?

I think there are 3 reasons: geography, intentionality, and sheer luck.

1)      Clearly we were not too close to the epicenter (25 miles away), but even households in our general area suffered more breakage and damage than we.  Part of the reason is that Alaska is piecemeal terrain.  Properties on boggy soil shook like jelly.  Construction on gravel soil seems to have been more fortunate than adjacent neighbors.   

2)      Our structures are all very simple rectangles with 90 degree walls and 45 degree rafters.  In more complicated homes that I visited, the structural cracks and spilled contents seem to have occurred most often on interior walls which connected to exterior ones, which may have contributed to bouncing and twisting  in various directions during the quakes.  

3)      We don’t have much breakable stuff.  When we moved to this remote home, we radically simplified, giving away and selling virtually all of our china, glassware, artwork.  In our small cabin, we have no glass picture frames on walls, no open shelves displaying fragile mementos.  We actually eat and drink from tin cups and plates.  So there wasn’t that much to break, other than my beloved glass mason jars. 

Propane tanks with straps

4)      Knowing that we live in earthquake country, we did implement some simple and cheap protective strategies.   All of our food storage shelves have front “lips” of 2 inches to contain short jars and 4 inches for tall mason jars.  Also, our chimney pipe and 100 lb propane tanks are all secured to adjacent buildings with metal earthquake straps.   Because we have thought about the dangers of fire, too, we have scattered clothes, food, sleeping accommodations, communications,  heat sources and jugs of water in various buildings on our five acres in case one is impaired and another not.  However, we have vulnerabilities, too, like a lack of extra glass to replace windows.  I am starting to insert cardboard dividers among the glass jars and rehang clocks and shelves with cup hooks and steeper angled nails and screws.  We will add lips to shelves that contain non glass storage items, too. 

I hope that we utilize this experience to learn a few life lessons, such as further strengthening our resilience to protect our simple home next time Mother Nature decides to shake her fist.