what can u do if a tsunami hit a marina??

[k88 7]

It does no look like a very big wave (looks like only half a meter), I cannot imagine what will happen if it is say even just 2 meters. Scary!

 

[wheels 543]

Not much you can do. Best you can do is get out and get to deep water as soon as you can. Restricted waterways are the most dangerouse. By restricted I mean, water ways that narrow in width or depth or both and even worse, are right at the end of a long bay/sound.

For instance, Havelock is at the end of a long narrow Sound, and at the end of a long narrow channel. At the extreme King tides, we can get 3.4M tides. Most are 3.1. Just around the corner which I guess would be 1000M, the same tide is just 1.5M.

The only saving Grace for Auckland is the Harbour entrance is narrow and would restrict what would get through and the inner harbour broadens greatly, along with many of the outer lying Islands being a good barrier.

[smithy09 50]

Got stuck in the Gironde River in France once.. Locals were lining the bank and I asked them why. They said "A big wave is coming" I said where was it, they said "there" and pointed to the wave about 150 metres downstream, probably 1.5 metres and breaking in parts. We were rafted 3 abreast on a floating dock, and we cut the lines of the boats outside and went out into the middle of the river. We rode it out no problem but the floating dock was thrown up on to the rock embankment.. Would have wrecked the boat. This was a tidal bore, not a Tsunami. but I imagine the effects are similar....

I take Tsunami warnings seriously now...

[Guest]

wheels watch the videos again, the surge came round corners, up rivers etc, if a big one hits the barrier is not going to save my or your arse

[wheels 543]

Perhaps I will reword and see if that helps, That the entrance to the Auckland harbour will give some restriction to any surge coming in, then, because the inner harbour area opens out, the surge that is coming through, would spread out and drop. Thus losing a lot of power. This is the Inner Auckland harbour and esturies only and it really does depend on the surge type and size. 100M high wave is going to go over most of Auckland. A 1M surge should be pretty much a non event within the inner harbour area.

Correct that the outerlying islands will not stop a surge. But they are a very winding waterway and that does actually help in some instances. In the Indonesian boxing day tsunami and the Samoan one for that matter, beaches in the direct path were flattened, beaches around the corner were unscathed. So there is certainly some aspects of a Tsunami that Direct path and non direct path can make a difference. I think the difference with those and this Japanese event is that we are not actually getting the Tsunami itself here, more a Tidal "Slosh" and yes that just flows around corners and up rivers etc.

It's a complex beast and the short texts of information I or anyone can post here can never do justice to such topics. I don't view any subject here in the general discussion Forum as being anything more than general discussion. It's certainly not Wikipedia, so please don't take discussion as Gospel.