
The Publisher
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Mar 14, 2011, 1:34 PM
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2011 Tsunami
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Dear Curmudgeon, Here's an update about the damage to Santa Cruz Small Craft Harbor. Garrison Keiler likes to start his monologues with the familiar "It's been a quiet week in Lake Wobegon, my home town", but it's been anything but quiet at the Santa Cruz Small Craft Harbor since Friday, March 11, 2011. As virtually anyone with a television knows, the tsunami caused by the terrible Japanese earthquake made its way across 5,000 miles of open ocean and arrived on our sunny shores on Friday morning. To be able to stand on the shore surrounding the harbor, in relative safety, and watch 800 boats crash and smash together for about 12 hours was something like watching a train crash in very, very slow motion. There were two modes of water movement and damage. The first was a series of surges which started at precisely 8:07 (right on time) on Friday and which continued until nightfall. Santa Cruz Harbor is long and skinny, having been dredged out of some wetlands in 1963 (try to get that past the Coastal Commission now...) so the water was flowing north and south with each cycle. I'd estimate that from flood to ebb to flood was about 25 minutes. http://maps.google.com/...93,0.033174&z=15 The current ran up and down the harbor at speeds approaching 10 knots, around hulls that had hull speeds of 5 knots, and docks which aren't normally subject to current. The harbor docks steadily weakened with each cycle, but relatively few boats broke free, and it appeared that surges would taper off and the harbor would be spared. That brings up the second mode of water movement. About two hours after the first signs of the tsunami, a series of waves entered the harbor. As you can see in the various videos, they looked like big ripples about 3' high and traveling extremely quickly. It was as if a large ship had powered past the mouth of the harbor and its wake had traveled up the harbor. This wave(s) wrenched the docks, boats, cleats, docklines, fenders, pilings and everything else with a violent snap. Apparently this happened two times, although it's hard to figure out the timing since various observers were at the harbor at various times, and no one seems to have the full story. I believe it was the first wave which fatally damaged U1-Dock in the upper harbor, which caused most of the boat damage and sinking. Saturday was surreal; tourists and boat owners were walking up and down the harbor, gawking at the enormous about of damage. As the surges continued (more quietly, but still related to the tsunami) you could see eddies in the water which indicated the location of sunken boats. The water, which is normally a somewhat turbid and blue, is a thick gray-black sludge. The greatest surprise was that the dock which gets violently shaken during the wave on Friday actually looks pretty normal on Saturday. It's made from recycled plastic and it's relatively new, so perhaps there's a lesson here. One more video that has inane commentary, but it shows the power of the current: http://www.youtube.com/...&feature=related Check out my hastily constructed blog at http://chuckhawley.blogspot.com/...tsunami-of-2011.html Regards, Chuck Hawley West Marine
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