Tsunami- Head Out To Sea?

[Dexterbase]

With the recent tsunami warning in Hawaii and the earthquakes off the coast of BC, I have been wondering about the best course of action if I were to get notification of a tsunami headed my way.

My boat is in Monterey on a mooring, and people feel our harbor is very well protected from tsunamis. Last year Santa Cruz got hit and a lot of boats and dock facilities were destroyed. Depending on the source of the tsunami, sure, Monterey could get hit pretty good.

So my question is this: if you had a boat moored in Monterey and a tsunami was forecast to hit, what would you do?

Throw on an extra pennant and make sure the boat is as ready as possible? Or get underway and head out to deep water? We have the deep submarine canyon right off shore, so getting into VERY deep water can happen in a matter of 30 minutes or so.

What would you do? Would your decision be any different if you were tied up to a slip in the harbor?

[Captain Jeffry]

Head out. Enjoy the day off shore. What's the downside? I guess the Crescent City folks would like a mulligan of that day!

[noelex 77]

Having seen in Sri Lanka the devastation a Tsunami can cause I think the best plan is to take no chances.
You don't have to be in very deep water for the effects of the tsunami to be minor.

[Dexterbase]

I'm also the closest mooring to the open water so if there's a traffic jam of like-minded owners thinking the same thing, I won't have a problem getting out of the harbor quickly.

[Paul L]

How deep is the water around your mooring?

[Ex-Calif]

It's a boat for Pete's sake. Check your tackle and head for high ground.

As they say in flying, "I'd rather be down here wishing I was up there than up there wishing I was down here."

[Richard5]

In Monterey I would head directly for the offshore canyon. Even very close to Moss Landing, the canyon is very close.

While water depth is a significant consideration it must be factored in with other conditions. Surge and the spilling wave are your greatest threats. One can be, hypthetically of course, in 200' of water but inside a turning basin with a narrow passage leading to outside. In that hypothetical condition you would experience a tremendous surge even though in "deep" water.

A portion of the breakwater in Long Beach, California suffered significant damage during high waves from a storm to the south. Curiously, no where else along the coast suffered nearly as much damage. Investigation revealed a rock reef just offshore of the breakwater acted to refract the waves onto that portion of the breakwater even though this was outside the 100 fathom curve.

If I were moored or anchored inside the bight between, say Monterey headlands and Sand City, I would head into the offshore canyon. Conversely, it is interesting to note that those nearest Moss but outside the harbor may suffer less from a tsunami. That last is my person opinion and based on knowledge of the ocean bottom features.

[Astrid]

It depends on how much time you have and how fast you can get into deep enough water not to be in danger. Where I am, under 50 miles from the epicenter of the quake off Haida Gwaii and facing an extended expanse of shallow water, it would have taken me too long to get to water deep enough to be safe. On the other hand, if I had four hours warning, I would head out to open water. In this last weekend's situation, with only a short warning, I simply got dressed warmly, grabbed my rucksack with survival kit grabbed my cat, left the boat and headed for high ground.

[DumnMad]

Heading for high ground in some places means heading for the traffic jam when the real escape route is underneath you. Also depends if you have enough warning.

[Astrid]

Not a whole lot of potential traffic here, and I would have a drive of about half a mile to a safe zone and could walk the rest of the way to one of the assembly points

[roverhi]

Best to go to sea if you can get to deep water before the first wave hit. No problems with any boats that went to sea here in Kona for the Japan quake. Two of those that stayed in harbor sank and a number of boats were damaged. We have the benefit of deep water close to shore so don't have far at sea to go. I was less than a 1/2 mile offshore in 50-75 feet of water when the waves that wiped out Alii Drive in downtown Kailua-Kona. Didn't know anything had happened until I tried to drive through town the next day.

Fwiw, those waves that did the damage hit 5 hours after the first tsunami wave hit the islands. The wave that wiped out Hilo in the '46 tsunami was the third of the widely spaced waves. Death toll was so high because people had gone out on the flats to pick up stranded fish. They weren't concerned because the first two waves were so gentle.

[Dexterbase]

Water at my mooring is from 34-38 feet(ish)

I can control the condition of my tackle and pennants, but what concerns me is the large fishing boats and whale watching boats moored near me. If one of those breaks loose my little 31 footer wouldn't even slow it down.

In the videos I watched of even the comparatively "small" tsunami that hit Santa Cruz, there were large boats that broke loose and just plowed into everything in their path.

I'm pretty confident that I can be in a thousand feet of water in half an hour or so. A couple thousand feet in not much longer. Monterey has a massive submarine canyon that comes pretty much right up to shore.

I think that I would feel better being out there and have the tsunami roll under me, than at the port watching the boats breaking loose and piling up.

I'm a skydiver so I definitely get the "rather be down here wishing I was up there, than up there wishing I was down here" analogy. Precisely why if I have warning I think it would be best to get out and into some deep water.

I'm very interested in all the thoughts here.

[Bash]

I had a boat in Moss Landing (next harbor north of Monterey) for 14 years. First time they issued a tsunami warning, the first thing I did was call my insurance agent and ask whether I was insured for a tsunami.

I was.

I left the boat in the harbor. All the uninsured guys took their boats out into the center of the bay. As I understand it--and I was listening on the VHF--the biggest problem was maintaining space away from the other boats out there.

[Captain Jeffry]

Originally Posted by Bash

I had a boat in Moss Landing (next harbor north of Monterey) for 14 years. First time they issued a tsunami warning, the first thing I did was call my insurance agent and ask whether I was insured for a tsunami.

I was.

I left the boat in the harbor. All the uninsured guys took their boats out into the center of the bay. As I understand it--and I was listening on the VHF--the biggest problem was maintaining space away from the other boats out there.

Just a wee bit curious why you wouldn't want to protect your boat even if you had insurance. Maybe really good insurance ~

[DumnMad]

Interesting thought Bash. The uninsured voted going to sea was a safe and diligent option.
I wonder what your insurer would think if your boat got trashed and their's didn't. Hopefully the policy would pay up no questions asked if you are in a marina.