Short Seawalls Send the Wrong Message

A flood control version of a restraining order...

The purpose is to keep water back, not keep dogs off the boardwalk (wry humor intended).

Yes, it is true.

Short border walls are not as effective as tall border walls at keeping out the tsunami of an impending flood.

And someone spent how much on a study to prove a tall wall is better at stopping a very tall wave than a short wall? Add to that the further study to prove people felt safe when any wall is in place, even one too short. Like that isn't obvious. Some of these studies these days....

They did not spend all-that-much (on this study):

it was happy hour, so the beer "waves" were pretty cheap. And the "sticky-notepad" (short wall) versus telephone directory (high wall) were no less "representative".

It's an easy-sell , for the wanna-be-wall-builders: more is better.

. . . but . . . my inquiring mind wants to know:

. . . which one is most likely going to simply "snap-off/bowl-over", and, in the end do very little (but toss money down the terlet)...?

And which would at least hold-back "something", hopefully minimizing the damage that would otherwise occur? There must be a limit to how many cubic miles of concrete can be poured-into such beasts... so: "pick any given HEIGHT". Without any lateral bracing, chances are it's a failure from the start. Thus, some of that *height* could/would/should go into such bracing, behind, as well as secondary efforts... (too many possibilities to mention).

Just axin' . . .

I just had to rant. I get a letter from Penn State every week on the research being done there, and quite frankly, at least once per month there is a research that has very obvious results without a study. I guess we must confirm EVERY belief these days and actually put percentages and numerical results to it. Or maybe they are just running out of ground breaking insights to research.

Okay, how did this happen? How did this blog (and title) draw the opposite conclusion from the other Engineering360 blog on the same research?

The author of this particular blog appears to have decided they knew where this article was going midway through the third paragraph....and stopped reading.

Completing the third paragraph would have been very enlightening. The second half of the quote results in the polar opposite of this blog author's assumption...

"However, our results cast serious doubt on this theory. The presence or size of seawalls and coastal forests does not strongly influence residents’ decisions on whether or not to evacuate.”

Researchers at UM are not suggesting shorter sea walls may cause greater damage, they are casting doubt on that theory.

Seawalls more than 5 meters high were shown to reduce damage, and more specifically, walls of 10 meters in height were associated with a 5% to 6% decrease in destruction rate. However, seawalls less than 5 meters high appear to have encouraged development in vulnerable areas and exacerbated damage.

Read the linked article again and get to the fourth paragraph copied above.

I have to admit, I too came away with a belief that both pro and con were presented for the short seawalls. Perhaps the linked article was written by a committee.

So, I reread.

I still come away with ambiguity as to the intended take away as well as whether or not this is valuable.