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Q: Could you survive a tidal wave by submerging yourself in an in-ground pool?

Randall’s response: A chart demonstrating that this idea both sounds dumber than and is actually dumber than “Invading Russia in winter” and “Plugging a power strip into itself to get free energy”.

My response: There are two main ways a “tidal wave” or tsunami can kill you. One is drowning, and the other is being hit by debris or swept along and slammed into a solid object.

Submerging yourself in an in-ground pool would only make the danger of drowning worse. You’d have to swim through more water to get back to the surface.

Being swept along and hit by debris, however, could possibly be prevented by jumping in the pool and getting underneath the wave, especially if you press yourself up against the side where the wave is coming from. Water waves involve a lot of horizontal motion with the surface of the water being pushed into swells and troughs. There isn’t a lot of vertical motion*, so when the wave washes over the pool, it might not disturb you if you’re fully under the surface.

Or maybe not. That much water being dumped in one end of the pool might just displace everything out of the pool as it sweeps across. Even if it doesn’t, the danger of heavy objects dropping into the pool and hitting you is very real. And worst of all, I suspect you wouldn’t be able to hold your breath long enough to wait for the fast-rushing water above you to stop, which would defeat the whole purpose.

In the case of a tsunami, the best advice is always to run to high ground. If there is no ground high enough to get above the wave, run anyway. Given the choice between running and jumping in an in-ground pool, I’d do my best to run somewhere I’d be less likely to get thrown against a solid object like, say, a street running parallel to the direction of the wave. That’s probably your best chance in such a dire situation.

*Note that “tidal wave” is a meaningless term that can be used for a number of phenomena, none of which precisely fit the popular conception of a very large wind-driven wave. Tsunamis involve movement of the whole body of the water, but the water in the pool is not included in this movement, so it doesn’t matter in this situation.