The Power of Water

Were New Orleans levees dynamited? By whom and why? Pick a conspiracy theory: “either by white racists in order to kill African-American residents, and/or by corporate ‘freelance’ special interests to provide lucrative public contracts — to companies like the neo-con corporations Halliburton and Blackwater?” Speculations, like this one e-mailed to me, spurred by websites like Hal Turner’s, “Explosive Residue Found on Failed Levee Debris, Ruptured New Orleans Levee Had Help Failing.

Without evidence, I cannot put credence in this story. So, we must await proof and hope if there is such proof it is not destroyed or covered up. In the absence of facts it is always possible to concoct a conspiracy theory — actually, even in the presence of facts (faith-based). I wish to offer three points in the interests of rationality.

“The levee ruptures in New Orleans did not take place during Hurricane Katrina, but rather a day after the hurricane struck.” — Hal Turner.

Hurricanes create a “storm surge,” a bulge of water above normal sea level, by the action of the wind. Since hurricanes cover a large area, so will this bulge. The “day the hurricane struck” would mean that the outer edge of the hurricane, as defined by meteorologists as some level of cyclonic wind speed, had arrived at “land” on the Gulf Coast. Land would probably be a coastal weather measurement station, or a tide-line as defined by the USGS, or simply a point observed from satellite images. New Orleans would be inland from this probable landfall at the outlet of the Mississippi river, perhaps quite a distance given the extent of the outlying delta landforms (islands and peninsulas).

The storm surge would raise the water level in a manner similar to a tsunami, and this hill of water would move inland with the hurricane. The added and increasing height of water within the levees channeling the Mississippi would greatly increase the pressure on the levee walls. This pressure would work to both strain the levees — like a membrane being stretched — and to infuse water through pores and cracks in the solid (earthen) material. Both effects work to weaken the ability of the material to counteract pressure — the levee turns to mud.

As an aside, a similar effect occurs during earthquakes, where the violent agitation of an earth-water interface (like lowlands along San Francisco Bay, or lake-bed sediments underlain by a water table under Mexico City) will allow for the rapid infusion of water through the earth, liquefying it and destroying its ability to bear stress — buildings sink into instant mud.

I would expect that the weakest spots in the levees around New Orleans liquefied first, and on the collapse of any strength-bearing property of this material simply became mud plugs in front of high pressure jets, which were shot out of the “nozzles” now made by these new gaps in the mass of the levees. A jet of water would chisel the hard ends of a levee break, giving it a streaked surface and the sharp contour of a “clean break.” Later, that portion of a break left in standing water would be softened.

“Several residents of New Orleans, and many Emergency Workers, reported hearing what sounded like large, muffled explosions from the area of the levee, but those were initially discounted as gas explosions from homes with leaking gas lines.” — Hal Turner

The rapid expulsion of the mud plugs at levee breaks would be your explosions, the corks popped. The actual “explosion” would simply be an air pressure wave created by the sudden rush of water (and mud). It may be possible that some masters thesis in civil engineering, in years to come, will show that these levees held up heroically beyond what should have been expected, given their design and their level of repair. But, we’ll see.

I do not doubt that one could create the disaster by dynamiting the levees, but such a claim requires firm evidence. I do not think the explosion of dynamite, presumably below water level and well within the levee, would necessarily have been greater or even noticeable in comparison to the air shock created by the breaching of the levee itself.

We are accustomed to seeing rivers, dams and levees, but many people do not realize the tremendous pressure a mass of water tens of feet high can produce, and over significant area — recall the impact of the recent Andaman Tsunami. The water level in New Orleans reached 20 feet or more, according to news reports. There are many miles of levees surrounding New Orleans. The storm surge may have topped the levees prior to their breaking (I’ve no data). A flood that crests your dam is usually one near its strength limit — if not beyond if the “safety factor” of the design is low or diminished because of lack of maintenance — and certainly produces flooding. Once flooding occurs, the effect of water and pressure begin working on both sides of the dam (or levee), which more rapidly weakens its base, where pressure is greatest.

“Burn marks on underwater debris chunks from the broken levee wall!” — Hal Turner.

Industrially, high pressure (fast) water jets are used to cut through metal and cement. It may be the case that the initial onrush of water through a levee break was of sufficient pressure to chisel, streak and even “burn” chunks of the fracturing levee surface, which is a concrete facing on the earthen mass.

Evidence once produced will tell its story, till then skepticism of the dynamite theory seems best.

Conspiracy theories are often red herrings thrown out to distract attention from the obvious, because those responsible for the obvious need an instant defense, or because there is a general reluctance to follow the moral question laid bare before your eyes.

My conclusions at this point are:

The power of water remains beyond the imagination of most people.

In America it is illegal to be an unelected mass murderer.

MANUEL GARCÍA, Jr., can be reached at: mango@idiom.com

 

 

 

Manuel Garcia Jr, once a physicist, is now a lazy househusband who writes out his analyses of physical or societal problems or interactions. He can be reached at mangogarcia@att.net