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Hydraulics
The most prominent designers of the Mississippi landscape are the Army Corps of Engineers. Their structures and operations make settlement in the Lower Mississippi Valley possible.
The Lower Mississippi begins at Cape Girardeau, Missouri. At this point, as Willard Price describes it, the “modest river hiding within its walls becomes a brazen exhibitionist riding on top of the world. . . . The river behind us is a dug-out river. It has made a trench for itself and the rock walls of the trench rise sometimes three hundred feet high. The river ahead of us had an entirely different idea. It rides on top of the land, somewhat like an aqueduct. You look down upon the upper river from the precipices that contain it. You look up to the lower river from lands that have to be protected from it by levees.” The Lower Mississippi has roamed the surface of the Lower Valley from Cairo to the Gulf like a monarch conjuring up mythical figures of the River King but also making it difficult to separate river from the land it makes. It has laid the alluvium of this valley, 30 to 90 miles wide and 600 miles long, over the last one million years, pushing back a sea.
The Army Corps of Engineers, at work in the Mississippi Valley from 1820 when they were first commissioned by Congress to survey the Lower Mississippi for navigation, have for over a hundred years battled the River King. In 1861, in the “Delta Survey,” they gave the Mississippi its definitive form - shape, depth, slope, discharge, and material. They also made it a ‘subject’ of hydraulics. This empirical science seeks information that is not merely directed to understanding river dynamics but also to carrying out engineering operations that control the river for study, operations such as levee-building, dredging, reservoir and floodway construction, stabilization of banks. Its purpose is “to determine the laws governing the flow of water in natural channels and to express these laws in new formulae which could safely and readily be used in practical application.” In 1879 Congress authorized this experimentation with the creation of the Mississippi River Commission. “The Commission was charged with the preparation of surveys, examinations, and the preparation and consideration of plans to improve the river channel, protect and stabilize the river banks, improve navigation, prevent destructive floods, and promote and facilitate commerce and the Postal Service.”
