Tsunami How-To ?

[GordMay]

Originally Posted by hoppy

If you are on a boat at anchor would you feel any shaking? I would have thought that the water would isolate you from any shaking?

I would have thought so, too - but maybe not.

We were fortunate to be able to witness the launch of the Space Shuttle “Endeavour” (September 12, 1992, 10:23:00.0680 a.m. EDT) from the Indian River (ICW South of Titusville). We anchored off the channel, about 10 miles from the launch pad. The nearest shore consisted of wetlands.
The noise, vibration, and SHAKING were incredible.
In retrospect, I cannot say whether the shaking was ground/water transmitted or air-born. Probably both.

[Tom Hildebrandt]

I have never been on my boat during an earthquake, but my wife was once in Ventura California while I was deployed overseas. She told me she noticed that some thing was not right but could not actally identify what was happening until she went into the cockpit and looked at the pontoons. They were bouncing all over the place, but the boat was more stable but still moving a bit. Inside of three minutes all the liveaboards in the marina were in the cockpit, engines started and with radios on to see what, where and how strong and if there were any warnings for boats. As it turns out, this was a relatively mild quake, I think around a 5 or so, and inland, not in the ocean.

[S/V Willow]

Hi Hoppy - I actually did ask the same question as we have never experienced an earthquake whilst aboard. (Despite living in the shaky isles) however from what others are saying it appears you do feel something. There again the people who were caught in this last one were tied up to a concrete wharf so I am sure that transmitted the movement fairly effectively.

Tom - I am not sure where they were anchored but it was behnd the two islands there. We actually visited one year later and the marina was just open again after being completely rebuilt. They have done a wonderful job but it was extremely quiet there with few boats.

We stayed in Patu Cetung (? not sure of spelling now) and the local shop keepers etc were telling us about the surge that hit them. They described it as a surge rather than as a wave but they didn't see it coming so it is all a matter of perspective I suppose.

I have just re-read my post and I sound judgemental which was not my intention. It is not my place to say in hindsight what should or should not be done by anyone and this situation was markedly different considering the speed with which the wave hit after the quake. All I can say is Thank you to anyone who posts any information about what they did and how they survived as it allows us all to learn and be thankful that they made it out.

[Tom Hildebrandt]

Moondust

I did not think your post was judgemental.

If your friends were behind the two islands, they were at Telaga, not at the Royal Yacht Club as I inititially surmised. And as you describe it, that is what the short video clip and few photos of the outer anchorage showed. The initial wall of water that came in through the gaps between the two islands was just about a meter high. That is what most of the boats in the anchorage had to face initially, then they had to fight the eddies. Once the wall approached the shore it rose up into a large wave and broke, but the water surge continued to rise behind the wave and flooded into the marina proper creating the whirlpool. This happened with all three waves. The marina had a pretty long video of the "washing machine action) I hope you had a chance to see that! And you are right, they had rebuilt the marina, raised the concrete pilings by another 7 or 8 feet, and that first year, the marina was essentally empty, but the next year it was full and they raised the prices by almost 50%!

I actually arrived on my boat the year after the tsunami, the same year you were there, and I may even have met and chatted with your friends if they were still in Telaga! I spent almost two years cruising between Malaysia (Port Dickson) and Thailand! Perhaps the best cruising grounds I have been in.

Regards

Tom

[S/V Willow]

Ouch 50%! My goodness it's a great harbour but thats a little OTT. I haven't seen any footage at all of the Telaga Harbour - do you have a link for it?

So jealous of you but with any luck we will be there in the next two years.

[senormechanico]

Quite a few years ago, we were onboard at anchor during an earthquake. It was about a 3.8 as I remember. It felt just like being on land, and after talking with friends who had experienced it on land, the motions were similar.

Steve B.

[MarkJ]

Originally Posted by GordMay

We were fortunate to be able to witness the launch of the Space Shuttle “Endeavour” (September 12, 1992, 10:23:00.0680 a.m. EDT) .

I saw the next one of Endevour! 1993-01-13 Saw the launch from the Media bay
STS-54 - Wikipedia, the free encyclopedia

That was the loudest noise I've ever heard was like the loudest part of thunder and just kept going one.. And the rumbling - like an earthquake.

My all consuming thought was that man can be very powerful for good in this world.

[maxingout]

We were cruising Thailand when the Asian tsunami hit Phuket. We were lucky because we had just sailed out of Naiharn Bay and about thirty minutes later the tsunami came through. We didn't see any waves near us, but the current around our yacht was swirling and very fast. I saw waves breaking on offshore islands, and remarked that it was perhaps not a good day to be moving to another harbor if it was going to be rough. About that time, we heard on the VHF that a tsunami had struck Phuket. We turned around and in about thirty minutes we were back in Naiharn bay looking at a debris line that was about half a mile offshore, and when we went into the bay, the northern half of shoreline had been obliterated by the tsunami. Buildings were gone, and structures twisted and crushed by the tsunami. Most yachts were anchored in more than forty feet of water and didn't suffer damage from the tsunami in the bay. The lesson I learned from that experience is that if I am in a tsunami zone, it is better to anchor in deep water where there will be a lot of current flowing around the boat without a massive tsunami wave hitting the yacht. Up until that experience, my wife always wanted to anchor close to shore. After the tsunami, she happily anchored if fifty feet of water in earthquake/tsunami zones.

[Tom Hildebrandt]

Hi Maxxingout!

I loved Naiharn Bay!

And glad to hear first hand form someone who confirmed my impression that 40+ feet is the place to be anchored!

Moondust

I no longer have the link, but I will scout arond and see if I can find it.

Soon you will be in thailand on your baot, just keep the eye on the goal!

Tom

[Pelagic]

Originally Posted by cdennyb

If you're throttled up and headed straight away too deep water, when the water went outward wouldn't you start really hauling buttt as compared to the land around you but still making 8knots or whatever in reference to the water?
I bet if you were lucky you could see some really good numbers on the GPS to show your friends! Asumming you made it out alive.
LoL

One thing to remember when running in fast water like that is to keep sufficient RPM in reserve, so as to have reliable steerage to get out of trouble.

You are focusing on keeping in the main current flow, which will carry you safely out.

Overflows and back eddies can kick you around but those who are familiar with running fast water like Dent rapids in BC Canada, know how to read the water and steer thru whirlpools in a way to keep pushing you back into the mainstream.

[maxingout]

Originally Posted by Tom Hildebrandt

Hi Maxxingout!

I loved Naiharn Bay!

And glad to hear first hand form someone who confirmed my impression that 40+ feet is the place to be anchored!

After going through the Thailand Tsunami without damage, I must admit feeling uncomfortable anchoring north of Kickem Jenny when we were cruising in the Caribbean. I knew if that volcano erupted with an earthquake, we would be toast anchored in twelve feet of water. Lesson learned.

[quartersplash]

This was sent to me from a friend on his boat in American samoa on the day of the sunami.

When we arrived here we did not find good holding for the anchor but were content and complacent when it snagged on something. The bottom is littered with debris and some wrecks. I had put down a second anchor because of strong winds on arrival but had taken it in yesterday in preparation for leaving today. So this morning while having coffee I felt a long lasting vibration through the hull. I have never felt an earthquake on the boat before so did not recognize what was happening. A short time later maybe 10-20 minutes the boat suddenly jerked sideways and water started rushing out of the harbor exposing shoals that had been about six ft or more deep. Knowing this was a sure warning of a Tsunami I started the engine and tried to get the anchor up. There was chaos all around and then the water started coming back in again, ships were being carried down on us, cars were going past, the water was full of debris. The anchor windlass tripped out one time and I thought about casting the anchor free but finally got it clear of the water far enough to find it was hooked on a chain evidently used as hurricane mooring. I was able to tie it up lower the anchor away and then cut the chain loose and motor clear. We motored for the next two hours around the harbor while smaller surges came and went finally re anchoring about 1130 local. While motoring we found out that my friend Danny was missing from the vessel Mainly and later found he had drowned. I did not go too far away from the pier but what I saw of the town was a disaster. I understand the water went pretty far inland at the head of the bay, some boats were carried with it, two ships were washed ashore but subsequently were pulled off. There is one boat on top of the pier and many building are gone. I looked on the internet and there is coverage of this disaster

Joe
By Gary on Archies Way Bahia De Caraquez

[Reality Check]

Originally Posted by GordMay

I would have thought so, too - but maybe not.

We were fortunate to be able to witness the launch of the Space Shuttle “Endeavour” (September 12, 1992, 10:23:00.0680 a.m. EDT) from the Indian River (ICW South of Titusville). We anchored off the channel, about 10 miles from the launch pad. The nearest shore consisted of wetlands.
The noise, vibration, and SHAKING were incredible.
In retrospect, I cannot say whether the shaking was ground/water transmitted or air-born. Probably both.

You would have been floored if it were a night time Saturn Launch. They made the slow turn down the coast. As I recall the first was the massive light changing night into a strange daylight but with a nighttime outline at the fringe then the Sound and vibrations in the Air which shook your insides then the increasing and waining vibrations of the ground and you could see ripples in the Indian River. I was not in a boat except for two of these but observed almost every launch from 1976 until about 1997. I worked in Melbourne, Titusville and the Cape. The two I saw from boats were... well they were stink pots and that killed much of the sensory abilities and a few drinks probably didn't help either.

I think you probably would feel an earth quake in a sailboat if you were in good contact with it (not on cushions} because I do feel the big engines of boats passing when I'm out setting on the deck. I've been through a couple of earthquakes in Turkey and was a good bit away from the epicenter, but definitely felt them.