California Earthquake Clearinghouse

COPRI2011_ChileThe attached poster was presented at the ASCE Coasts, Oceans, Ports, and Rivers Institute Conference in Alaska in June, 2011.  The poster compares the effects and observations from the 2010 Chile and 2011 Japan tele-tsunamis in California.  The reference for the poster is:

Wilson, R., Ewing, L., Dengler, L., Boldt, E., Evans, T., Miller, K., Nicolini, T., and Ritchie, A., 2011, Effects of the February 27, 2010 Chilean Tsunami on the harbors, ports, and the maritime community in California, with comparison to preliminary evaluation of March 11, 2011 tsunami: American Society of Civil Engineers, Coasts, Oceans, Ports, and Rivers Institute, Solutions to Coastal Disasters Conference, Anchorage, AK, June 26-29, 2011: poster session.

The following pictures were taken by the brother of HSU Geology Alumni Nathan Hayler.  All credit goes to Charlie Hayler, the photographer.

Charlie Hayler went to Murray Field where he took his small plane up in the air the morning of March 11, 2011 to view the incoming tsunami which was a result of the Honshu, Japan earthquake.  All time stamps are of Pacific Standard Time.  Photos taken at 8:30 and 8:34 are of the mouth of the Mad River, McKinleyville, California, photos taken at 8:40 AM are further north at the mouth of Little River, near Moonstone Beach, Westhaven California.  The final photo is just north of there.  You can see the parking lot above Luffenholtz Beach and Scenic Drive, south of Trinidad, CA.

This website also includes information, photos, video on the tsunami in Hawaii:

http://walrus.wr.usgs.gov/news/field.html

It’s been a very busy three days (and nights).  The tsunami is still ringing in Crescent Harbor – amplitudes are about 20% of the peak and below hazard levels but still too high to safely work in the harbor or send in divers to assess the situation beneath the water.  There is a diesel spill and other hazmat concerns.  Ten boats sank – 9 of them deposited in the boat basin and one sailboat swept out into the larger harbor and deposited near the mouth of Elk Creek.  Some accounts mention 11 sunk boats – but that counts one that sank about 7 years ago.  Most of these boats were derelict or little used.  There are concerns that some of the rock bank failed and sediments were deposited on the basin floor.  We won’t know the full impacts until an underwater assessment can be completed.  All of the damage appears confined to the boat basin – I have yet to hear of any significant problems in the inner or outer harbor.   I don’t have the exact count of the boats that put to sea before the tsunami arrived – it seems to be in the neighborhood of 25.  The process of notification of boat owners began late Thursday evening and seems to have gone well.  The evacuation was orderly.  This event points out the importance of tsunami plans at all ports and harbors, even small ones like Crescent City and Brookings.  While leaving the harbor seems to have gone smoothly, not all captains were prepared for the long offshore wait or had sufficient fuel to make it to alternate port.  As Friday afternoon wore on, concerns grew about when the boats could come back to port and where they could dock.  The closest undamaged facility was in Humboldt Bay but several boats couldn’t make it that far.  There was also concern about a storm due to arrive late Friday evening.  Humboldt Bay has one of the most hazardous entrances of any West Coast port and smaller boats can only safely enter on flood tides.  So the decision had to be made to allow boats back into the ports while the advisory was still in effect.  The boats with insufficient fuel returned to Crescent City.  They docked at the south side of the outer harbor where the currents were not as strong.  Most of the Crescent City fleet along with a number of boats from Brookings went to Humboldt – we observed a steady stream of boats crossing through the mouth from about 6 PM to midnight.

I’ve only document one instance of overland flow in Del Norte County.  Tsunami amplitudes just before High High tide a little after 3 AM Saturday morning reached a little over a meter and caused the highest water stand (about 2.8 meters above MLLW) of the whole event.   Deputy Sheriffs observed water “boiling onto the roadway” at the campground near Elk Creek.  They will provide me with a detailed high water line when I return tomorrow.  This highest water stand occurred around the 40th cycle and 20 hours after the first wave arrival.  The effect of the ambient tide was huge in this event.  Had the tsunami occurred 6 hours earlier or 18 hours later, major on-land flooding would have occurred.

Some docks and boats were torn off well before the high amplitude short period waves came through at around 11:13 & 11:18. On the second strong ebb a sinking vessel struck the O’Neill catamaran’s port pontoon. From what I understand, it had been tied up at the end of a dock section, and was torn loose and capsized. Probably on the first wave. 

Clearly those waves did some damage, but there was plenty of energy (and damage) before they came through.

I have minimal video/pictures, since I was taking measurements the entire time, but there were several hundred people and a couple helicopters that got good film of the whole shebang, so I imagine that you can get a clear picture of when and where the damage occurred if somebody’s willing to compile all of that. Probably would be useful to talk to the chopper folks. I think at least one of them got the whole thing.

Last night I dreamed I was helping to build a tsunami gate for Santa Cruz harbor

http://www.surfline.com/surf-news/japan-devastated-hawaii-and-west-coast-of-us-largely-spared-by-pacific-ocean-wide-tsunami_53348/

I spoke to Rich Young the Harbor Master at Crescent City.  He estimated 25 boats had left the harbor.  A handful came back in around 6 pm because they didn’t have enough fuel to get to Humboldt.  They are anchored on the south side of the main harbor.  You can see the new Humboldt fleet at the Woodley Island Marina.  It’s great that so many folks were able to safely get out and save their life’s work and resources.

http://www.youtube.com/watch_popup?v=1MDnlcbRMaQ&

Very useful map of Tide Data:

http://tidesandcurrents.noaa.gov/tsunami/#