The cold and wild winter ocean beats and breaks against the banks,
pulls up beach grass clumps, drags the sand into offshore depths, down,
exposing rocks and old spruce roots in the grey clay ground. The ocean
takes what it wants and throws back the rest to sit and to rot and to be
picked at by birds. The waves roll in big now, pushed along by winds
that howl across the open Pacific. The night is filled with their deep
thunderous sounds. The big waves remind me: an anniversary is upon us.
Three hundred years ago this month, on January 26, 1700, giant waves rose
up, engulfing houses and trees and people along the Oregon coast,
dragging them out into the cold nighttime sea. Three hundred years ago,
tsunamis crashed through our hometown.
What we know o f Oregon coast tsunamis is limited by our
comparatively brief tenure here - since European peoples first reoccupied this
coast, no waves have loomed as large as those that arrived 300 years ago.
Still, small tsunamis have recently visited our shores, giving us hints
o f what has come before. Many locals still recall the events o f 1964,
when an earthquake centered in southern Alaska's Prince William Sound
sent a wave down the Pacific coast. Reaching a maximum height o f over
200 feet in Alaska, these waves were only around 10 feet high when they
arrived on the Oregon coast. When the Alaska tsunami arrived in Cannon
Beach, it rushed inland up Ecola Creek, taking out the town's main
bridge and tumbling trailers. Then, having reached far upstream, the
wave lost momentum and fanned out into the trees, returning as a seaward
current o f water coursing through the forest. My grandparents' house,
located in the north end o f town, was knocked from its foundation by
rushing water and hurtling logs. Family legend informs us that the
neighbor's house was tossed into the broad lateral branches o f a spruce
tree on my grandparents' property. When the waters receded, the
neighbor who owned this house approached my grandfather, asking
permission to climb into the tree so that he could retrieve some o f his
belongings. My grandfather, a cautious man by nature, visions o f
personal liability litigation dancing in his head, ultimately
consented. In time, houses were pulled down from trees, and placed -
with much labor and complaint - back onto their foundations. We were
comparatively lucky this time. Surging across the Pacific from its
Alaskan epicenter, this same wave drowned people in Alaska, as well as
Newport and the northern California coast, caused significant damage in
such far-flung locations as Hawaii and Japan, and was detectable as far
away as Chile and Antarctica. Small tribal villages on the British
Columbia and Alaska coasts, places occupied for centuries, containing
small remnant populations o f elderly epidemic survivors and young
fishermen, were wiped away; their homes and docks destroyed; these
people drifted o ff to places such as Vancouver and Seattle. It marked
the end, the final blow, for more than one tribe. Here and there on our
coast, one can still see weathered gray logs perched in improbably high
places, sitting right where the tsunami placed them in 1964. Young trees
grow back densely near the shoreline, where waves swept their
predecessors clean.
i,
Tsunamis are by no means rare in the seismically active Pacific basin.
Usually, there are about two tsunamis per year in the Pacific Ocean,
while waves that are large enough to be detectable around the entire
Pacific occur only every 10 to 12 years. These giant waves are created
by the rapid displacement o f large amounts o f water - most often they
are generated by earthquakes, but they can also result from other
disturbances: volcanic eruptions, meteor impacts, or the large
landslides - above or below the water's surface - that sometimes follow
earthquakes. These waves pulse outward at tremendous speeds, a rushing
lateral shockwave that is detectable from the ocean's surface to its
floor. In the open sea, these waves can often reach speeds o f 600 miles
per hour. Tsunamis have extremely long wavelengths; sometimes, in the
open ocean, over a hundred miles separates the crest o f each successive
wave, while they may be only a few inches or feet in height. To ships
at sea, they often are not detectable (the Japanese, in particular, have
many ominous tales o f fisherman returning to a destroyed home port, not
having noticed the wave passing beneath their boats at sea).
When these waves enter shallows, however, the wave's energy becomes
increasingly focussed - the wavelength rapidly decreases, the wave
slows, and its height begins to increase. The resulting surge o f water
can arrive as a large breaking wave, or in more subtle forms - as a
standing wave, or simply as a very rapid rise in the water level.
Tsunamis commonly arrive in rapid succession after an earthquake.
Numerous waves may crash into the shore, continuously, for several hours
after the initial tsunami, and often the first wave is not the biggest.
The size that these waves reach is a matter o f the severity o f the
earthquake (or other disturbance), the contours o f the nearshore sea
floor, the distance between the wave's origin and the point o f landfall,
the tide, and a number o f other factors that coastal residents might
simply summarize under the heading 'dumb luck'. Waves o f up to 50 feet
can result from earthquakes far across the Pacific, while waves o f over
100 feet are not uncommon in locations near an earthquake's epicenter.
(For reference. Haystack Rock is 235 feet high.) Still, they can be
much much bigger. Waves o f 500 feet can be detected archaeologically in
portions o f the Pacific. And, in 1958, following a large landslide,
Lituya Bay, Alaska was struck by a wave that was 1,722 feet high. We can
only guess how large tsunamis have become in the past; we can only
imagine what it must be like to witness these monster waves.
Locally, historically, the largest tsunamis appear to have been caused
by earthquakes along a long belt referred to by geologists as the
"Cascadia subduction zone." This line demarcates the seam in the
Earth's crust where two tectonic plates meet Here, the "Juan de Fuca
plate," underlying our offshore waters, slides under the much larger
"North American plate" along an offshore north-south line, running from
northern Vancouver Island in British Columbia to Cape Mendocino in
California. The heavier oceanic plate slips below our continent, but it
doesn't do this smoothly. It does so in plunging fits and starts,
building up pressure and then releasing this tension with a rapid
forward slide. When this happens, there is often a large earthquake.
And, as was the case in January o f 1700, when this last happened, there
is a tsunami. Sometimes, during these events, the land also rises or
falls relative to the sea, rapidly and permanently perching beaches high
above the high tide line, or submerging forests below the sea. Some o f
the trunks and tree roots exposed on our beach by this winter's waves
outline where whole forests were submerged, killed by the saltwater, and
buried below the accumulating beach sand when the land dropped, 300
years ago. Up and down our coast, north and south o f us, the roots and
stumps o f similar coastal forests lie buried in beach sand and bay mud.
These large subduction zone earthquakes and tsunamis occur every 200 to
600 years, but arrive at an average interval o f roughly 300 years.
Which makes this 300 year anniversary so very interesting. Which,
according to Michael Burgess' Guide to the Real Oregon Coast, makes
"last week the safest time to visit the Oregon Coast for the next few
decades"
♦
European people have not yet seen these big waves, have not
experienced the awesome force o f a subduction zone earthquake and tsunami
on this coast Our history here is too brief, the timing o f our rapid
reoccupation too serendipitous. Despite this, we can pinpoint the last
major tsunami to the night o f January 26th, 1700. This is done on the
basis o f archaeological evidence, as well as the meticulous records o f
the Japanese, whose east coast was battered by 10-foot high tsunamis in
the two days following this earthquake
The Native peoples that lived on this coast when Europeans first
arrived were direct descendants o f the survivors. While they did not record
their history with reference to specific calendar dates, they spoke
clearly o f the tsunami that struck 300 years ago this year, and o f other
tsunamis from times more distant. Many mentioned huge waves that
arrived two or three or four generations before the first whites
arrived, coming at night, sweeping through their villages. On Vancouver
Island's west coast, for example, indigenous people still speak o f this
last major tsunami: "they simply had no time to get ahold of their
canoes, no time to get awake, no one ever knew what happened, a big wave
smashed into the beach." In one community, only the family that lived
in a longhouse on a hill, perched above the rest o f the village, was not
overtaken by the waves and "did not drift out to sea with the others" -
the tribe largely consisted o f this family's descendents when whites
arrived. Legends from up and down the Oregon coast describe the ocean
going far inland after earthquakes o f unknown antiquity, "sweeping
everything away clean." Others speak o f the ocean ebbing away, as often
happens before a tsunami, giving certain people an early warning and the
opportunity to go to high peaks; members o f several tribes still can
point to peaks to which their ancestors retreated for safety. Legends
suggest that some people were able to ride out rapidly rising waters in
large cedar canoes, but were separated from the others, drifting to
faraway places. Tsunamis, we can gather from these tales, were a widely
understood, terrifying aspect o f everyday life.
Archaeological evidence lends support to many o f these tales.
Slowly, from the sediments and debris o f former village sites along this coast,
a coherent picture emerges: whole villages were demolished by these
subduction zone earthquakes and tsunamis. Many were permanently
abandoned. Layers o f debris, marking hundreds o f years o f human
occupation, cease abruptly at the same moment that earthquakes and
tsunamis rearranged the local landscape. Some villages were permanently
submerged with water as the land abruptly dropped relative to the sea.
In a number o f nearby places, including the western margins o f Nehalem
Bay, village sites were submerged into the intertidal zone; soon
thereafter, nearby, other villages seem to be established anew. The
timing o f these events, these rapid relocations, appear to correspond
with the timing o f subduction zone quakes and the tsunamis that
followed. With an empathetic imagination, we might envision the
personal stories, the awesome human drama, associated with the events
that made these signatures in the soil.
Our people have never seen this kind o f destruction on this coast. As
imagination is required to envision the tsunamis o f the past, a little
imagination is required to envision events yet to come. With our
burgeoning, unprecedented population, a subduction zone quake and
tsunami could result in a natural disaster with few modem parallels.
(By all means, if you feel a major quake, head for the hills.) Now,
confronted with growing evidence o f the timing and severity o f past
tsunamis, some communities are contemplating their response. And how
does one respond to the immanent but unpredictable threat o f oceanic
destruction on a Biblical scale? The City o f Cannon Beach and a few
other coastal towns have built tsunami alert systems, tied in to a
network o f seismic and oceanic monitoring stations around the Pacific.
The reassuring sound o f a very agitated cow, played over Cannon Beach
loudspeakers every month or so, lets us know that this system is still
functioning and can - with adequate forewarning - alert us o f
approaching waves. (A cow, it was determined, sounds much less
intimidating to the average tourist than the siren that would sound If
This Were An Actual Emergency.) The City' has also posted blue signs to
evacuation routes o f unknown merit, featuring a stick figure-ish
individual about to be swept away by a large curling wave. Other towns
may soon follow these examples. History provides them with a valuable
lesson: three hundred years ago, tsunamis crashed through our hometown.
Tsunamis will come again. It could be tomorrow or another three hundred
years into the future - the distinction is not significant in geologic
time. By looking at where the waves have hit, and how high they have
been, we might be better prepared. We might, unlike many o f the people
who lived here on that January night, 300 years ago, be able to get to
high ground before the giant waves return again.
The verbal account o f the 1700 tsunami comes from Arima, St. Claire,
Clamhouse, Edgar, Jones, and Thomas (1991). Between Ports Albemi and
Renfrew: Notes on West Coast Peoples. (Canadian Ethnology Service
Mercury Series Paper # 121). Ottawa: Canadian Museum o f Civilization.
Michael Burgess is quoted from his 1998 Left Coast Group book, Uncle
Mike's Guide to the Real Oregon Coast, which includes an illuminating
section on tsunami watching that 1 would quote in full here if space
permitted. A number o f very good tsunami sites are available on the
internet. Start, perhaps, with the West Coast and Alaska Tsunami Warning
Center at http://wcatwc.gov/ and explore from there
Lnjoy the peaceful beauty
US/ and natural surroundings o f
"Willapa Bay and the north
end o f the Cong Beach 'Peninsula.
FEATURING THE CUISINE
of Rosio A riste
OPENING FOR DINNERS
IN LATE JUNE
CALL FOR THE DAY S MENU:
(360) 665-4543
MOBY
HOTEL & OYSTER FARM
Hrmofiht
WiiJOroer w Wiiizjju
Located in Sahtau. Washington on Sandndge RdJust South of Bay Avenue
(DON’T BE A VICTIM OF INFERIOR FRAMING)
AWARNING
1287 Commercial Si., Ariona, OR 97103 • Phone (503) 325-5221
S
U T r tR u r r iD U J ftm m o o o
1
4