The Why Files The Why Files --

The Why Files Book Club presents: Dave & Megan 'Nerd's the Word'

A controlling force?
Book cover with title and drawing of men building a damTo a journalist, little elicits envy like reading John McPhee. He specialized in geology, layering flawless phrases into lucid paragraphs that are as textured but seamless as sedimentary rock. Nowhere is this more evident than in "Control of Nature" (see bibliography) which stacks up three of his New Yorker articles about epic efforts to tame nature.

The San Gabriel Mountains above Los Angeles are doing what old mountains do naturally: Crumbling. That's not good for Angelenos, who happen to be doing what they do naturally: building in the hills. The result is landslides, and expensive efforts to evade gravity.

'Control' looks at three epic struggles against water, gravity and lava.When a volcano started issuing a flood tide of lava near a town in Iceland, it threatened to close a harbor that was crucial to a nation that depends on fishing. The Icelandic solution was to stream endless tons of sea water onto the lava, making a mythic battle between Earth's fiery interior and its watery surface.

And then there's "Atchafalaya," about the massive effort to regulate the Mississippi River around New Orleans. The "Old River Control Structure," part of that effort, is a gargantuan hunk of concrete that is supposed to prevent the Mississippi from doing what comes naturally -- shortcutting down the Atchafalaya River to the Gulf of Mexico.

In the deltas where large rivers meet the ocean, they naturally seek new routes to the sea, but nature would be a catastrophe for Louisiana. If -- or more likely when -- the Mississippi flushes down the Atchafalaya, it would high-and-dry New Orleans and starve the huge industrial complex north of town of fresh water and access to the sea.

The river's natural preferences conflict with an edict of the U.S. Congress, which has assigned the Sisyphean task of containing the Mississippi in its current channel to the U.S. Army Corps of Engineers. Old River Control is one of many impressive structures built for this purpose.

But the Mississippi is impressive as well, taking water from more than 40 percent of the lower 48 states. During the flood of 1973, the control structure was severely undermined by the floodwaters. As McPhee describes the effort to plumb the damage after the flood, he closes with a left-hook sentence that shows off his spare, direct style:

"The structure was obviously undermined, but how much so, and where? What was solid, and what was not? With a diamond drill, in a central position, they bored the first of many holes in the structure. When they had penetrated to basal levels, they lowered a television camera into the hole. They saw fish."

"They saw fish." Pow! Not "Their camera found water where they expected to see foundation," or "They couldn't find a bit of concrete under their concrete."

No siree! "They saw fish." Full stop.

From the control structure and the colorful Cajuns who run it, McPhee works effortlessly outward to the larger picture of environmental change at the mouth of the Mississippi. Endless square miles of wetlands are subsiding without the sediment they once got from a river that is now channeled between levees. The wetlands and barrier islands south of New Orleans both moderate hurricanes, but as they disappear, the storms are getting stronger, and the storm surges higher.

River winds through flood plain.
The old river control structure in Louisiana was designed to feed some water from the Mississippi River into the Atchafalaya River. Otherwise, the Atchafalaya will steal the entire Mississippi and become the outlet to the Gulf of Mexico, leaving New Orleans high and dry. Photo: USGS

In McPhee's history of levee-building along the Mississippi, we are introduced to the push-me, pull-you logic of river containment: If the levee on your side of the river breaks or leaks during a flood, I'll benefit because the river will drop as it floods your town. If we build levees on both banks, the river will stop running over its banks during a flood. The river will be higher, and we'll both need to build taller levees.

McPhee is even-handed. Even though he obviously likes a lot of the locals who earn their living by sticking their fingers in the Louisiana dikes, he questions the dogged pursuit of levee-building. Is it a solution to, or a cause of, Mississippi floods?

Ultimately, McPhee suggests, the river will break into the Atchafalaya and take a shortcut to the Gulf. That's how deltas work, all over the world. The Corps can hem the river in for a while, but it can't fight nature forever.

Why do some societies collapse while others prosper for 1,000 years?


Megan Anderson, project assistant; Terry Devitt, editor; S.V. Medaris, designer/illustrator; David Tenenbaum, feature writer; Amy Toburen, content development executive

©2022, University of Wisconsin, Board of Regents.