Boundary Issues: Clarifying New Orleans's Murky Edges

Abstract

At first there were just titiy ridges flanking the river, barely perceptible piles of Big Muddy s mud. Then, over millennia, they grew as the Mississippi River deposited layers of soil during flood seasons. It happened like this: Before the advent of modern flood control technologies, when the swollen river spread from its channel each spring, the unconstrained torrent slackened. Without a current carrying it, suspended material sank. The heaviest sediment dropped closest to the river, with lighter silt falling farther away. So the Mississippi built its banks, earthen ramps descending gradually from its shores. We know these accretions as the river's natural levees.' Eventually, the levees became useful for people, because of both local topography and continental geography. Native Americans knew the riverbanks as the highest, driest ground in the flat, damp delta. They shared their knowledge with the Europeans who settled Louisiana. For the latter, the Mississippi and its levee embodied the New Worlds promise. The river gathered the waters of thousands of smaller streams crisscrossing its valley, an expanse stretching from the Rockies' eastern face to the Alleghenies' western slope. More than fifteen thousand miles of navigable waterways make up the Mississippi system, a funnel whose spout would, it seemed, shunt trade inexorably toward the Gulf of Mexico. For boosters the Mississippi was God's signature carved into the valley; they saw in the turbid river images of empire. And the levee was more evidence of a divine plan: an elevated spot on which to build an entrepot where produce gathered from the North American interior could arrive at market near the river mouth.^